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Halawani A, Paterson R, Zhong T, Du K, Ren R, Forbes CM. Risks and side effects in the medical management of benign prostatic hyperplasia. Prostate Int 2024; 12:57-64. [PMID: 39036761 PMCID: PMC11255900 DOI: 10.1016/j.prnil.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/14/2023] [Accepted: 11/30/2023] [Indexed: 07/23/2024] Open
Abstract
Benign prostatic hyperplasia affects up to 80% of men in their lifetime. It causes bladder outflow obstruction, leading to lower urinary tract symptoms, which can have a large impact on quality of life. Lifestyle modifications and pharmacotherapy are often offered as first-line treatments for patients. These include alpha blockers, 5-alpha-reductase inhibitors, phosphodiesterase-5 inhibitors, anticholinergics, B3-agonists, and desmopressin. While often well tolerated, these pharmacotherapies do have significant side effects, which both clinicians and patients should understand and discuss in order to make an informed treatment decision among alternatives. The purpose of this review is to provide a current overview of the risks and side effects of commonly used medications in benign prostatic hyperplasia management.
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Affiliation(s)
- Abdulghafour Halawani
- Department of Urology, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Ryan Paterson
- Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Tianshuang Zhong
- Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Katie Du
- University of Alberta, Edmonton, Alberta, Canada
| | - Runhan Ren
- Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Connor M. Forbes
- Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
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2
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da Silva SB, Feitosa SGD, de L Alves SM, Santos RCA, Dos Anjos JV, Araújo AV. A Concise and Useful Guide to Understand How Alpha1 Adrenoceptor Antagonists Work. Mini Rev Med Chem 2022; 22:2383-2405. [PMID: 35507746 DOI: 10.2174/1389557522666220504141949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 02/23/2022] [Accepted: 03/16/2022] [Indexed: 11/22/2022]
Abstract
Adrenoceptors are the receptors for the catecholamines, adrenaline and noradrenaline. They are divided in α (α1 and α2) and β (β1, β2 and β3). α1-Adrenoceptors are subdivided in α1A, α1B and α1D. Most tissues express mixtures of α1-adrenoceptors subtypes, which appear to coexist in different densities and ratios, and in most cases their responses are probably due to the activation of more than one type. The three subtypes of α1-adrenoceptors are G-protein-coupled receptors (GPCR), specifically coupled to Gq/11. Additionally, the activation of these receptors may activate other signaling pathways or different components of these pathways, which leads to a great variety of possible cellular effects. The first clinically used α1 antagonist was Prazosin, for Systemic Arterial Hypertension (SAH). It was followed by its congeners, Terazosin and Doxazosin. Nowadays, there are many classes of α-adrenergic antagonists with different selectivity profiles. In addition to SAH, the α1-adrenoceptors are used for the treatment of Benign Prostatic Hyperplasia (BPH) and urolithiasis. This antagonism may be part of the mechanism of action of tricyclic antidepressants. Moreover, the activation of these receptors may lead to adverse effects such as orthostatic hypotension, similar to what happens with the antidepressants and with some antipsychotic. Structure-activity relationships can explain, in part, how antagonists work and how selective they can be for each one of the subtypes. However, it is necessary to develop new molecules which antagonize the α1-adrenoceptors or make chemical modifications in these molecules to improve the selectivity, pharmacokinetic profile and/or reduce the adverse effects of known drugs.
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Affiliation(s)
- Sidiane B da Silva
- Laboratório de Nutrição, Atividade Física e Plasticidade Fenotípica - Centro Acadêmico de Vitória - Universidade Federal de Pernambuco. R. Alto do Reservatório, s/n Bela Vista - Vitória de Santo Antão, PE, 50608-680, Brazil
| | - Sidney G D Feitosa
- Departamento de Química Fundamental - Universidade Federal de Pernambuco. Av. Jornalista Aníbal Fernandes, s/n, Cidade Universitária - Recife, PE, 50740-560, Brazil
| | - Silvia M de L Alves
- Laboratório de Nutrição, Atividade Física e Plasticidade Fenotípica - Centro Acadêmico de Vitória - Universidade Federal de Pernambuco. R. Alto do Reservatório, s/n Bela Vista - Vitória de Santo Antão, PE, 50608-680, Brazil
| | - Ruth C A Santos
- Laboratório de Nutrição, Atividade Física e Plasticidade Fenotípica - Centro Acadêmico de Vitória - Universidade Federal de Pernambuco. R. Alto do Reservatório, s/n Bela Vista - Vitória de Santo Antão, PE, 50608-680, Brazil
| | - Janaína V Dos Anjos
- Departamento de Química Fundamental - Universidade Federal de Pernambuco. Av. Jornalista Aníbal Fernandes, s/n, Cidade Universitária - Recife, PE, 50740-560, Brazil
| | - Alice V Araújo
- Núcleo de Saúde Pública, Centro Acadêmico de Vitória - Universidade Federal de Pernambuco R. Alto do Reservatório, s/n Bela Vista - Vitória de Santo Antão, PE, 50608-680, Brazil
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3
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Alsufyani HA, Docherty JR. Roles for α 1-adrenoceptors during contractions by electrical field stimulation in mouse vas deferens. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY 2021; 25:525-532. [PMID: 34697263 PMCID: PMC8552829 DOI: 10.4196/kjpp.2021.25.6.525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 11/15/2022]
Abstract
We have investigated the relative roles of α1-adrenoceptors and purinoceptors in contractions to low and high frequency stimulation of the mouse vas deferens, in terms of the time course of responses. In separate experiments, isometric contractile responses were obtained to 10 pulses at 1 Hz and 40 pulses at 10 Hz. Responses to 1 Hz stimulation consisted of a series of discrete peaks. The α1A-adrenoceptor antagonist RS100329 (10–9M–10–7M) significantly reduced the response to the first pulse, the α1D-adrenoceptor antagonist BMY7378 (10–7M–10–6M) significantly reduced the response to the first two pulses, and the non-selective α1-adrenoceptor antagonist prazosin (10–8M) reduced the response to the first 4 pulses at 1 Hz. Responses to 10 Hz stimulation consisted of an early peak response and a maintained plateau response. RS100329 significantly reduced the peak response but did not significantly affect the plateau response. Prazosin, significantly reduced both the peak and plateau responses. The α1A-adrenoceptor antagonist RS17053 in high concentrations reduced mainly the plateau response leaving a clear early peak response. The plateau response of contraction was almost abolished by the purinoceptor antagonist suramin. These results suggest that there is a relatively minor early α1D-adrenoceptor and a larger early α1A-adrenoceptor component to stimulation-evoked contractions of mouse vas deferens, but the major α1-adrenoceptor component is revealed by prazosin to be α1B-adrenoceptor mediated. α1B-Adrenoceptor activation probably facilitates contractions mediated by other α1-adrenoceptors and by purinoceptors. These results suggest that combined non-selective α1-adrenoceptor blockade, particularly α1B-adrenoceptor blockade, in addition to P2X1-purinoceptor blockade is useful in reducing male fertility.
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Affiliation(s)
- Hadeel A. Alsufyani
- Department of Physiology, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - James R. Docherty
- Department of Physiology, Royal College of Surgeons in Ireland (RCSI), Dublin D02 YN77, Ireland
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4
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Archer M, Dogra N, Dovey Z, Ganta T, Jang HS, Khusid JA, Lantz A, Mihalopoulos M, Stockert JA, Zahalka A, Björnebo L, Gaglani S, Noh MR, Kaplan SA, Mehrazin R, Badani KK, Wiklund P, Tsao K, Lundon DJ, Mohamed N, Lucien F, Padanilam B, Gupta M, Tewari AK, Kyprianou N. Role of α- and β-adrenergic signaling in phenotypic targeting: significance in benign and malignant urologic disease. Cell Commun Signal 2021; 19:78. [PMID: 34284799 PMCID: PMC8290582 DOI: 10.1186/s12964-021-00755-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 05/28/2021] [Indexed: 01/17/2023] Open
Abstract
The urinary tract is highly innervated by autonomic nerves which are essential in urinary tract development, the production of growth factors, and the control of homeostasis. These neural signals may become dysregulated in several genitourinary (GU) disease states, both benign and malignant. Accordingly, the autonomic nervous system is a therapeutic target for several genitourinary pathologies including cancer, voiding dysfunction, and obstructing nephrolithiasis. Adrenergic receptors (adrenoceptors) are G-Protein coupled-receptors that are distributed throughout the body. The major function of α1-adrenoceptors is signaling smooth muscle contractions through GPCR and intracellular calcium influx. Pharmacologic intervention of α-and β-adrenoceptors is routinely and successfully implemented in the treatment of benign urologic illnesses, through the use of α-adrenoceptor antagonists. Furthermore, cell-based evidence recently established the antitumor effect of α1-adrenoceptor antagonists in prostate, bladder and renal tumors by reducing neovascularity and impairing growth within the tumor microenvironment via regulation of the phenotypic epithelial-mesenchymal transition (EMT). There has been a significant focus on repurposing the routinely used, Food and Drug Administration-approved α1-adrenoceptor antagonists to inhibit GU tumor growth and angiogenesis in patients with advanced prostate, bladder, and renal cancer. In this review we discuss the current evidence on (a) the signaling events of the autonomic nervous system mediated by its cognate α- and β-adrenoceptors in regulating the phenotypic landscape (EMT) of genitourinary organs; and (b) the therapeutic significance of targeting this signaling pathway in benign and malignant urologic disease. Video abstract.
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Affiliation(s)
- M. Archer
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - N. Dogra
- Department of Pathology and Molecular and Cell Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Department of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - Z. Dovey
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - T. Ganta
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Division of Hematology and Medical Oncology, Mount Sinai Hospital, New York, NY USA
| | - H.-S. Jang
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - J. A. Khusid
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - A. Lantz
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institute, Stockholm, Sweden
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - M. Mihalopoulos
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - J. A. Stockert
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - A. Zahalka
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - L. Björnebo
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - S. Gaglani
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - M. R. Noh
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - S. A. Kaplan
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - R. Mehrazin
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - K. K. Badani
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - P. Wiklund
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - K. Tsao
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Division of Hematology and Medical Oncology, Mount Sinai Hospital, New York, NY USA
| | - D. J. Lundon
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - N. Mohamed
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - F. Lucien
- Department of Urology, Mayo Clinic, Rochester, MN USA
| | - B. Padanilam
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - M. Gupta
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
| | - A. K. Tewari
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - N. Kyprianou
- Department of Urology, Icahn School of Medicine at Mount Sinai, 6th Floor, 1425 Madison Avenue, New York, NY 10029 USA
- Department of Pathology and Molecular and Cell Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY USA
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5
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Chmielarz P, Kuśmierczyk J, Rafa-Zabłocka K, Chorązka K, Kowalska M, Satała G, Nalepa I. Antidepressants Differentially Regulate Intracellular Signaling from α1-Adrenergic Receptor Subtypes In Vitro. Int J Mol Sci 2021; 22:ijms22094817. [PMID: 34062902 PMCID: PMC8124549 DOI: 10.3390/ijms22094817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 11/16/2022] Open
Abstract
Currently utilized antidepressants have limited effectiveness and frequently incur undesired effects. Most antidepressants are thought to act via the inhibition of monoamine reuptake; however, direct binding to monoaminergic receptors has been proposed to contribute to both their clinical effectiveness and their side effects, or lack thereof. Among the target receptors of antidepressants, α1‑adrenergic receptors (ARs) have been implicated in depression etiology, antidepressant action, and side effects. However, differences in the direct effects of antidepressants on signaling from the three subtypes of α1-ARs, namely, α1A-, α1B- and α1D‑ARs, have been little explored. We utilized cell lines overexpressing α1A-, α1B- or α1D-ARs to investigate the effects of the antidepressants imipramine (IMI), desipramine (DMI), mianserin (MIA), reboxetine (REB), citalopram (CIT) and fluoxetine (FLU) on noradrenaline-induced second messenger generation by those receptors. We found similar orders of inhibition at α1A-AR (IMI < DMI < CIT < MIA < REB) and α1D‑AR (IMI = DMI < CIT < MIA), while the α1B-AR subtype was the least engaged subtype and was inhibited with low potency by three drugs (MIA < IMI = DMI). In contrast to their direct antagonistic effects, prolonged incubation with IMI and DMI increased the maximal response of the α1B-AR subtype, and the CIT of both the α1A- and the α1B-ARs. Our data demonstrate a complex, subtype-specific modulation of α1-ARs by antidepressants of different groups.
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Affiliation(s)
- Piotr Chmielarz
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
| | - Justyna Kuśmierczyk
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
| | - Katarzyna Rafa-Zabłocka
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
| | - Katarzyna Chorązka
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
| | - Marta Kowalska
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
| | - Grzegorz Satała
- Department of Medicinal Chemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland;
| | - Irena Nalepa
- Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland; (P.C.); (J.K.); (K.R.-Z.); (K.C.); (M.K.)
- Correspondence: ; Tel.: +48-12-6623225
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6
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Qin X, Li W, Yang X, Ma Z, Liang D, Luo X, Chen X, Hu S, Du L, Chai L, Li M. Photoinduced Electron Transfer-Based Fluorescent Agonists for α 1-Adrenergic Receptors Imaging. Anal Chem 2021; 93:6034-6042. [PMID: 33830731 DOI: 10.1021/acs.analchem.0c03841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The novel fluorescent agonists were discovered herein for α1-adrenergic receptors (α1-ARs) based on photoinduced electron transfer (PeT) off-on switch by conjugating the fluorophore 7-(diethylamino)coumarin-3-carboxylic acid with phenylephrine. After careful evaluation, these probes exhibited efficient binding affinity with α1-ARs and could be applied to selectively imaging α1-ARs or successfully tracing the dynamic process of α1-AR internalization in living cells. Meanwhile, a bioluminescence resonance energy transfer binding assay with these new probes has been well-established and applied. Therefore, these PeT-based on-off agonists may serve as powerful tools for the α1-AR-associated study during drug discovery.
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Affiliation(s)
- Xiaojun Qin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China.,School of Pharmacy, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Wenhua Li
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Xingye Yang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Zhao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China.,Department of Biochemistry and Molecular Medicine, UC Davis Comprehensive Cancer Center, University of California-Davis, Sacramento, California 95817, United States
| | - Dong Liang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Xiongfeng Luo
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Xinxin Chen
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Shilong Hu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Lupei Du
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Lijuan Chai
- Department of Internal Medicine, Hospital of Shandong University, Jinan, Shandong 250012, P. R. China
| | - Minyong Li
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China
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Yu B, Zheng X, Sun Z, Cao P, Zhang J, Gao Z, Cao H, Zhang F, Wang W. The safety and efficacy of doxazosin in medical expulsion therapy for distal ureteric calculi: A meta-analysis. PLoS One 2021; 16:e0245741. [PMID: 33493214 PMCID: PMC7833139 DOI: 10.1371/journal.pone.0245741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 01/06/2021] [Indexed: 11/28/2022] Open
Abstract
Purpose Alpha-adrenergic receptor blockers can be effectively used in the context of medical expulsion therapy (MET) to treat ureteric stones. This study was designed to evaluate the safety and efficacy of doxazosin in MET relative to placebo or tamsulosin. Methods We systematically searched the PubMed, the Cochrane Library, EMBASE, Chinese Academic Database, and Web of Science databases to select randomized controlled trials (RCT) that compared the use of doxazosin with placebo or tamsulosin to treat ureteric stones. All patients we included were limited to those diagnosed with visible stones in the distal ureter. The diameter of ureteric stones does not exceed 10 mm. Results Eight trials comparing doxazosin with placebo or tamsulosin containing 667 patients were assessed in the final analysis. The meta-analysis showed that doxazosin effectively treated ureteric stones and was better than placebo in terms of efficacy. Relative to the placebo group, the expulsion rate of stones from the distal ureter (OR = 3.00, 95% CI [2.15, 4.19], I2 = 0%, P < 0.00001) was significantly increased, and the expulsion time (days) was shortened (mean difference) (MD) = −4.03, 95% CI [−4.53, −3.53], P < 0.00001). The doxazosin group experienced fewer pain episodes (MD = −0.78, CI = [−0.94, −0.23], I2 = 0%, P < 0.00001) than the placebo group. A subgroup analysis showed that the doxazosin group had a higher expulsion rate (of 5–10 mm stones) compared with the placebo group. Although doxazosin resulted in significantly more adverse effects compared with the placebo, the patient’s symptoms were mild and no further medical interventions were required. Moreover, the expulsion time (days) was shorter for patients receiving doxazosin (MD = −0.61, 95% CI [−0.97, −0.24], I2 = 39%, P = 0.001) than those receiving tamsulosin. Conclusion Compared with the placebo group, patients receiving doxazosin had a greater expulsion rate, a reduced expulsion time, and fewer pain episodes. The expulsion time of doxazosin was shorter than that of tamsulosin.
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Affiliation(s)
- Baozhong Yu
- Affiliated Beijing Chaoyang Hospital of Capital Medical University, Beijing, China
| | - Xiang Zheng
- Affiliated Beijing Chaoyang Hospital of Capital Medical University, Beijing, China
| | - Zejia Sun
- Affiliated Beijing Chaoyang Hospital of Capital Medical University, Beijing, China
| | - Peng Cao
- Capital Medical University, Beijing, China
| | | | - Zihao Gao
- Capital Medical University, Beijing, China
| | | | | | - Wei Wang
- Affiliated Beijing Chaoyang Hospital of Capital Medical University, Beijing, China
- * E-mail:
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8
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Proudman RGW, Pupo AS, Baker JG. The affinity and selectivity of α-adrenoceptor antagonists, antidepressants, and antipsychotics for the human α1A, α1B, and α1D-adrenoceptors. Pharmacol Res Perspect 2020; 8:e00602. [PMID: 32608144 PMCID: PMC7327383 DOI: 10.1002/prp2.602] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/26/2022] Open
Abstract
α1-adrenoceptor antagonists are widely used for hypertension (eg, doxazosin) and benign prostatic hypertrophy (BPH, eg, tamsulosin). Some antidepressants and antipsychotics have been reported to have α1 affinity. This study examined 101 clinical drugs and laboratory compounds to build a comprehensive understanding of α1-adrenoceptor subtype affinity and selectivity. [3H]prazosin whole-cell binding was conducted in CHO cells stably expressing either the full-length human α1A, α1B, or α1D-adrenoceptor. As expected, doxazosin was a high-affinity nonselective α1-antagonist although other compounds (eg, cyclazosin, 3-MPPI, and ARC239) had higher affinities. Several highly α1A-selective antagonists were confirmed (SNAP5089 had over 1700-fold α1A selectivity). Despite all compounds demonstrating α1 affinity, only BMY7378 had α1D selectivity and no α1B-selective compounds were identified. Phenoxybenzamine (used in pheochromocytoma) and dibenamine had two-component-binding inhibition curves at all three receptors. Incubation with sodium thiosulfate abolished the high-affinity component suggesting this part is receptor mediated. Drugs used for hypertension and BPH had very similar α1A/α1B/α1D-adrenoceptor pharmacological profiles. Selective serotonin reuptake inhibitors (antidepressants) had poor α1-adrenoceptor affinity. Several tricyclic antidepressants (eg, amitriptyline) and antipsychotics (eg, chlorpromazine and risperidone) had high α1-adrenoceptor affinities, similar to, or higher than, α blockers prescribed for hypertension and BPH, whereas others had poor α1 affinity (eg, protriptyline, sulpiride, amisulpiride, and olanzapine). The addition of α blockers for the management of hypertension or BPH in people already taking tricyclic antidepressants and certain antipsychotics may not be beneficial. Awareness of the α-blocking potential of different antipsychotics may affect the choice of drug for those with delirium where additional hypotension (eg, in sepsis) may be detrimental.
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Affiliation(s)
- Richard G. W. Proudman
- Cell Signalling Research GroupDivision of Physiology, Pharmacology and NeuroscienceSchool of Life SciencesC Floor Medical SchoolQueen’s Medical CentreUniversity of NottinghamNottinghamUK
| | - Andre S. Pupo
- Department of PharmacologyInstitute of BiosciencesSão Paulo State UniversityBotucatu‐São PauloBrazil
| | - Jillian G. Baker
- Cell Signalling Research GroupDivision of Physiology, Pharmacology and NeuroscienceSchool of Life SciencesC Floor Medical SchoolQueen’s Medical CentreUniversity of NottinghamNottinghamUK
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9
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Ismail MMF, Soliman DHS, Elmoniem MHA, Jaleel GAA. Synthesis, Molecular Modeling of Novel Substituted Pyridazinones and their Vasorelaxant Activities. Med Chem 2020; 17:171-186. [PMID: 32216740 DOI: 10.2174/1573406416666200327191100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 02/04/2020] [Accepted: 02/04/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Hypertension, one of the most common cardiovascular diseases that can cause coronary disease, stroke, myocardial infarction, and sudden death, it is the major contributor to cardiac failure as well as renal insufficiency. OBJECTIVES As there are many cardio-active pyridazinone-base derivatives in clinical use, therefore, we aimed to synthesize a new series of pyridazin-3-ones and evaluate their vasorelaxant activity. METHODS A new series of synthesized compounds were carried out first by the synthesis of 6- flouroarylpyridazinones by cyclization of 3-(4-flourobenzoyl) propionic acid with hydrazine hydrate or arylhydrazines to provide the corresponding pyridazinone derivatives 2a-d. Mannich reaction was performed using morpholine or piperidine formaldehyde to obtain compounds 3a,b. On the other hand, reaction of 2a with various chloroacetamide intermediates, in dimethylformamide and potassium carbonate as a catalyst, afforded the target compounds 5a-c. The aromatic acid hydrazide intermediates 6a-g were prepared in 50-90% yield, by reacting to the prepared esters with hydrazine hydrate under reflux in ethanol. The two compounds 8a,b were prepared via condensation of 7a,b with ethyl chloroacetate in dry acetone. Finally, the target 2,4,6-trisubstituted pyridazinones 9a-c derivatives were obtained by the reaction of 7a with the appropriate aromatic aldehyde or substituted acetophenones. The new compounds were then evaluated for their vasorelaxant properties using isolated thoracic rat aortic rings. In addition, a homology model was built and molecular modeling simulation of these compounds into the active sites of the newly created α1a-adrenoceptor model was performed in order to predict and rationalize their affinities toward this receptor. RESULTS Among these compounds; 5a was the most potent, it exhibited approximately two-times the activity of prazosin (IC50 = 0.250, 0.487 mmol, respectively) also, fourteen compounds were more potent than prazosin.
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Affiliation(s)
- Magda M F Ismail
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt
| | - Dalia H S Soliman
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt
| | - Mona H Abd Elmoniem
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt
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Qin X, Ma Z, Yang X, Hu S, Chen X, Liang D, Lin Y, Shi X, Du L, Li M. Discovery of Environment-Sensitive Fluorescent Agonists for α1-Adrenergic Receptors. Anal Chem 2019; 91:12173-12180. [DOI: 10.1021/acs.analchem.9b01059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Xiaojun Qin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Zhao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
- Department of Biochemistry and Molecular Medicine, UC Davis Comprehensive Cancer Center, University of California, Davis, Sacramento, California 95817, United States
| | - Xingye Yang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Shilong Hu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Xinxin Chen
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Dong Liang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Yuxing Lin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Xiaodong Shi
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Lupei Du
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Minyong Li
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong 250100, China
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Quaresma BMCS, Pimenta AR, Santos da Silva AC, Pupo AS, Romeiro LAS, Silva CLM, Noël F. Revisiting the Pharmacodynamic Uroselectivity of α 1-Adrenergic Receptor Antagonists. J Pharmacol Exp Ther 2019; 371:106-112. [PMID: 31285236 DOI: 10.1124/jpet.119.260216] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/02/2019] [Indexed: 12/17/2022] Open
Abstract
α1-Adrenoceptor (AR) antagonists are widely used for the relief of urinary retention secondary to benign prostatic hyperplasia (BPH). While the five Food and Drug Administration-approved α 1-AR antagonists (terazosin, doxazosin, alfuzosin, tamsulosin, and silodosin) share similar efficacy, they differ in tolerability, with reports of ejaculatory dysfunction. The aim of the present work was to revisit their α 1-AR subtype selectivity as well as of LDT5 (1-(2-methoxyphenyl)-4-[2-(3,4-dimethoxyphenyl) ethyl]piperazine monohydrochloride), a compound previously described as a multitarget antagonist of α 1A-/α 1D-AR and 5-HT1A receptors, and to estimate their affinity for D2, D3, and 5-HT1A receptors, which are putatively involved in ejaculatory dysfunction. Competition binding assays were performed with native (D2, 5-HT1A) or transfected (human α 1A-, α 1B-, α 1Dt-AR, and D3) receptors for determination of the drug's affinities. Tamsulosin and silodosin have the highest affinities for α 1A-AR, but only silodosin is clearly a selective α 1A-AR antagonist, with K i ratios of 25.3 and 50.2 for the α 1D- and α 1B-AR, respectively. Tamsulosin, silodosin, and LDT5 (but not terazosin, doxazosin, and alfuzosin) have high affinity for the 5-HT1A receptor (K i around 5-10 nM), behaving as antagonists. We conclude that the uroselectivity of tamsulosin is not explained by its too-low selectivity for the α 1A- versus α 1B-AR, and that its affinity for D2 and D3 receptors is probably too low for explaining the ejaculatory dysfunction reported for this drug. Present data also support the design of "better-than-LDT5" new multitarget lead compounds with pharmacokinetic selectivity based on poor brain penetration and that could prevent hyperplastic cell proliferation and BPH progression. SIGNIFICANCE STATEMENT: The present work revisits the uroselectivity of the five Food and Drug Administration-approved α1 adrenoceptor antagonists for the treatment of benign prostatic hyperplasia (BPH). Contrary to what has been claimed by some, our results indicate that the uroselectivity of tamsulosin is probably not fully explained by its too-weak selectivity for the α1A versus α1B adrenoceptors. We also show that tamsulosin affinity for D3 and 5-HT1A receptors is probably too low for explaining the ejaculatory dysfunction reported for this drug. Based on our lead compound LDT5, present data support the search for a multitarget antagonist of α1A-α1D and 5-HT1A receptors with poor brain penetration as an alternative for BPH treatment.
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Affiliation(s)
- Bruna Maria Castro Salomão Quaresma
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - Amanda Reis Pimenta
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - Anne Caroline Santos da Silva
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - André Sampaio Pupo
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - Luiz Antonio S Romeiro
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - Claudia Lucia Martins Silva
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
| | - François Noël
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (B.M.C.S.Q., A.R.P., A.C.S.d.S., C.L.M.S., F.N.); Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, Brazil (A.S.P.); and Health Sciences Faculty, Universidade de Brasília, Brasília, Brazil (L.A.S.R.)
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12
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Tang H, Lui C, Tsui K, Fung H. Terazosin versus Alfuzosin in Treatment of Acute Urinary Retention in Patients with Benign Prostatic Hypertroph. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791502200402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective To compare the efficacy and adverse reactions of terazosin and alfuzosin in treatment of acute urinary retention in patients with benign prostatic hypertrophy. Design Case control study. Setting Emergency department of a regional hospital in Hong Kong. Methods Our study included all adult male with age at least 18 years old presented with acute urinary retention, having residual urine volume greater than or equal to 300 ml after urinary catheterisation and with a presumed diagnosis of benign prostatic hypertrophy. Patients treated with terazosin from December 2013 to February 2014 were retrospectively included while patients treated with alfuzosin from April to September 2014 were prospectively included. We compared the two groups on: trial without catheter (TWOC) rate, potential adverse effects including drug-associated postural hypotension, haemodynamic changes and prolongation of corrected QT interval in electrocardiogram. Cost effectiveness analysis was performed. Results A total of 116 patients were included with 59 and 57 patients in the terazosin and alfuzosin group respectively. Logistic regression showed that residual urine volume (odds ratio [OR]=0.998, 95% confidence interval [CI]=0.996-0.999, p=0.008) and presence of precipitating factors (OR=2.264, 95% CI=1.045-5.793, p=0.045) were independent predictors of successful TWOC. There was no significant difference in the TWOC rate for patients treated with alfuzosin and terazosin. There was significantly more symptomatic postural hypotension in the terazosin group compared with the alfuzosin group. The number need to treat with alfuzosin for terazosin to avoid one adverse drug effect was 12.3 patients (95% CI=4.7-21.6) and 9.9 patients (95% CI=5.3-84.6) to reduce one postural hypotension and symptomatic postural hypotension respectively. Conclusions Alfuzosin is comparable to terazosin in TWOC rate. However, alfuzosin is associated with a lower rate of symptomatic postural hypotension and less haemodynamic impact than terazosin. (Hong Kong j.emerg.med. 2015;22:210-218)
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Affiliation(s)
- Hn Tang
- Tuen Mun Hospital, Department of Accident and Emergency Medicine, Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong
| | - Ct Lui
- Tuen Mun Hospital, Department of Accident and Emergency Medicine, Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong
| | - Kl Tsui
- Tuen Mun Hospital, Department of Accident and Emergency Medicine, Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong
| | - Ht Fung
- Tuen Mun Hospital, Department of Accident and Emergency Medicine, Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong
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13
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Benign Prostatic Obstruction Relief in Patients with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Enlargement Undergoing Endoscopic Surgical Procedures or Therapy with Alpha-Blockers: A Review of Urodynamic Studies. Adv Ther 2017; 34:773-783. [PMID: 28255867 DOI: 10.1007/s12325-017-0504-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Indexed: 01/22/2023]
Abstract
Benign prostatic obstruction (BPO) contributes to the genesis of lower urinary tract symptoms as well as to pathologic remodeling of the lower and upper urinary tract in patients with benign prostate enlargement. Urodynamic studies demonstrate that both medical therapy with alpha-blockers (ABs) and endoscopic surgical procedures provide BPO relief. However, the magnitude of improvement is higher after surgery. Among ABs, silodosin is associated with the highest improvement of bladder outlet obstruction index (BOOI). A complex relationship exists between BOOI improvement and variations of both maximum urinary flow (Q max) and detrusor pressure. When the reduction of BOOI is small, the improvement of Q max is clinically irrelevant and the BOOI is mainly influenced by a decrease of detrusor pressure. In contrast, when the magnitude of BOOI reduction is robust, a meaningful improvement of both detrusor pressure and urinary flow is evident. When clustering ABs according to their receptor pharmacologic selectivity and urodynamic efficacy, three subgroups can be identified,with silodosin being the only member of a subgroup characterized by the highest levels of BOOI improvement and α-1A/α-1B receptor affinity ratio.
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14
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Shimoda H, Takeda S, Shimizu N, Hirano M, Hitoe S. Suppressive effect of triterpenoids and a flavonol glycoside in seaberry extract on carbacol-induced contraction of bladder smooth muscle and TGF-β-induced contraction of collagen gel containing bladder smooth muscle cells. J Funct Foods 2017. [DOI: 10.1016/j.jff.2017.01.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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15
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Harris DA, Park JM, Lee KS, Xu C, Stella N, Hague C. Label-Free Dynamic Mass Redistribution Reveals Low-Density, Prosurvival α1B-Adrenergic Receptors in Human SW480 Colon Carcinoma Cells. J Pharmacol Exp Ther 2017; 361:219-228. [PMID: 28196836 DOI: 10.1124/jpet.116.237255] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 02/10/2017] [Indexed: 12/11/2022] Open
Abstract
Small molecules that target the adrenergic family of G protein-coupled receptors (GPCRs) show promising therapeutic efficacy for the treatment of various cancers. In this study, we report that human colon cancer cell line SW480 expresses low-density functional α1B-adrenergic receptors (ARs) as revealed by label-free dynamic mass redistribution (DMR) signaling technology and confirmed by quantitative reverse-transcriptase polymerase chain reaction analysis. Remarkably, although endogenous α1B-ARs are not detectable via either [3H]-prazosin-binding analysis or phosphoinositol hydrolysis assays, their activation leads to robust DMR and enhanced cell viability. We provide pharmacological evidence that stimulation of α1B-ARs enhances SW480 cell viability without affecting proliferation, whereas stimulating β-ARs diminishes both viability and proliferation of SW480 cells. Our study illustrates the power of label-free DMR technology for identifying and characterizing low-density GPCRs in cells and suggests that drugs targeting both α1B- and β-ARs may represent valuable small-molecule therapeutics for the treatment of colon cancer.
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Affiliation(s)
- Dorathy-Ann Harris
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Ji-Min Park
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Kyung-Soon Lee
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Cong Xu
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Nephi Stella
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Chris Hague
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
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Abstract
PURPOSE OF REVIEW Intraoperative floppy iris syndrome (IFIS) occurs in 2% of cataract surgeries and is associated with an increased risk of surgical complications. These complications can be avoided when high-risk patients are identified by preoperative screening and appropriate measures are used intraoperatively. The purpose of this article is to review emerging risk factors for IFIS and to summarize management strategies used in IFIS. RECENT FINDINGS Although α1-antagonists in general, and tamsulosin (Flomax, Jalyn) in particular, have long been associated with IFIS, recent studies have more firmly demonstrated the elevated risk of IFIS attributed to tamsulosin. This resulted in a revision of the American Society of Cataract and Refractive Surgery/American Academy of Ophthalmology guidelines on IFIS. Our understanding of additional medications and medical conditions involved in IFIS is also evolving, including an appreciation that women are also susceptible to IFIS. New modifications of techniques used in the intraoperative management of IFIS are also discussed. SUMMARY Preoperative screening should include both men and women. Current or prior use of α1-antagonists and antipsychotics should be documented, along with hypertension. Surgeons should be prepared to employ a range of perioperative interventions in a graded response to IFIS of different severities.
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Affiliation(s)
- Jennifer M Enright
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, USA
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Ma Z, Lin Y, Cheng Y, Wu W, Cai R, Chen S, Shi B, Han B, Shi X, Zhou Y, Du L, Li M. Discovery of the First Environment-Sensitive Near-Infrared (NIR) Fluorogenic Ligand for α1-Adrenergic Receptors Imaging in Vivo. J Med Chem 2016; 59:2151-62. [PMID: 26821136 DOI: 10.1021/acs.jmedchem.5b01843] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Zhao Ma
- Department of Medicinal Chemistry, Key Laboratory of
Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Yuxing Lin
- Department of Medicinal Chemistry, Key Laboratory of
Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Yanna Cheng
- Department of Pharmacology, School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Wenxiao Wu
- Department of Medicinal Chemistry, Key Laboratory of
Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Rong Cai
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Shouzhen Chen
- Department
of Urology, Qilu Hospital of Shandong University, Jinan, Shandong 250012, China
| | - Benkang Shi
- Department
of Urology, Qilu Hospital of Shandong University, Jinan, Shandong 250012, China
| | - Bo Han
- Department
of Pathology, School of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Xiaodong Shi
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Yubin Zhou
- Center for Translational Cancer Research, Institute of Biosciences & Technology, Texas A&M University Health Science Center, Houston, Texas 77030, United States
| | - Lupei Du
- Department of Medicinal Chemistry, Key Laboratory of
Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
| | - Minyong Li
- Department of Medicinal Chemistry, Key Laboratory of
Chemical Biology (MOE), School of Pharmacy, Shandong University, Jinan, Shandong 250012, China
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Huang W, Xue P, Zong, H, Zhang Y. Efficacy and safety of silodosin in the medical expulsion therapy for distal ureteral calculi: a systematic review and meta-analysis. Br J Clin Pharmacol 2016; 81:13-22. [PMID: 26255996 PMCID: PMC4693578 DOI: 10.1111/bcp.12737] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 07/06/2015] [Accepted: 08/03/2015] [Indexed: 11/29/2022] Open
Abstract
AIMS Using a selective α-adrenoceptor blocker for medical expulsive therapy (MET) is an effective treatment approach widely used for ureteral stones. The aim of the review was to assess the efficacy and safety of silodosin in medical expulstion therapy compared with placebo and tamsulosin. METHODS A systematic search was performed in PubMed, Cochrane Library and Embase to identify randomized controlled trials that compared silodosin with a placebo or tamsulosin for ureteral calculi. RESULTS Eight publications involving a total of 1048 patients were used in the analysis, which compared silodosin with placebo and tamsulosin. We found that silodosin was effective in treating ureteral calculi in our meta-analysis and was superior to tamsulosin in its efficacy. The expulsion rate of all ureteral stones (OR 1.59, 95% CI 1.08, 2.36, P = 0.02), the expulsion rate of distal ureteral stones (OR 2.82, 95% CI 1.70, 4.67, P < 0.0001) and the expulsion time (days) of distal ureteral stones (standard mean difference (SMD) -4.71, 95% CI -6.60, -2.83, P < 0.00001) indicated that silodosin was more effective than the placebo. Moreover, expulsion rate (OR 2.54, 95% CI 1.70, 3.78, P < 0.00001), expulsion time (days) (SMD -2.64, 95% CI -3.64, -1.64, P < 0.00001) and pain episodes (P < 0.00001) indicated that silodosin was more effective than the tamsulosin. Even though silodosin had a significant increase in abnormal ejaculation compared with tamsulosin, no significant differences were observed for complications (OR 1.00, 95% CI 0.58, 1.74, P = 1.00). CONCLUSIONS This meta-analysis indicated that silodosin was superior to placebo or tamsulosin in the efficacy for distal ureteral calculi with better control of pain. The safety profile of silodosin was similar to tamsulosin though retrograde ejaculation was worse for silodosin use. We conclude that silodosin might have potential as a MET for ureteral stones.
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Affiliation(s)
- Wei Huang
- Urology Department, Beijing Tian Tan HospitalCapital Medical University, Neurourology Research Division, China National Clinical Research Center for Neurological DiseaseBeijingChina
| | - Peng Xue
- Urology Department, Beijing Tian Tan HospitalCapital Medical University, Neurourology Research Division, China National Clinical Research Center for Neurological DiseaseBeijingChina
| | - Huantao Zong,
- Urology Department, Beijing Tian Tan HospitalCapital Medical University, Neurourology Research Division, China National Clinical Research Center for Neurological DiseaseBeijingChina
| | - Yong Zhang
- Urology Department, Beijing Tian Tan HospitalCapital Medical University, Neurourology Research Division, China National Clinical Research Center for Neurological DiseaseBeijingChina
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Alpha-Blocker Treatment Response in Men With Lower Urinary Tract Symptoms Based on Sympathetic Activity: Prospective, Multicenter, Open-Labeled, Observational Study. Int Neurourol J 2015; 19:107-12. [PMID: 26126440 PMCID: PMC4490311 DOI: 10.5213/inj.2015.19.2.107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/29/2015] [Indexed: 11/08/2022] Open
Abstract
Purpose: In this study, we compared the treatment outcomes for an α-blocker between 2 groups of men, one with high sympathetic activity (HSA) and another with low sympathetic activity (LSA) or normal sympathetic activity. Methods: A total of 159 men (≥50 years of age) with lower urinary tract symptoms resulting from benign prostatic hyperplasia were analyzed. We assigned patients to groups according to their sympathetic activity, which was evaluated by heart ratevariability measurements. HSA was defined as a low frequency/high frequency ratio greater than 1.6. All patients received 10mg of alfuzosin once a day for 12 weeks. The primary end point was a change in the total International Prostate SymptomScore (IPSS) at 12 weeks from baseline. Results: Sixty-seven men were assigned to the HSA group and 92 men were assigned to the LSA group. The baseline characteristics were not significantly different between the 2 groups, and the response to alfuzosin was good in both groups. Themean total IPSS change was not different between the groups. Both groups were not significantly different with respect to the changes in maximal flow rate, IPSS voiding or storage symptom subscores, quality of life, and rates of adverse drug events. TheHSA group showed a similar willingness to continue treatment compared to the LSA group, although their treatment satisfaction rating was lower. Conclusions: The therapeutic effects of alfuzosin did not differ in regards to the differences in sympathetic activity, but treatment satisfaction ratings were lower in the HSA group.
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Choi H, Sim JS, Park JY, Bae JH. Assessment of Tamsulosin 0.2 mg for Symptomatic Bladder Outlet Obstruction Secondary to Benign Prostatic Enlargement: Data from a Korean Multicenter Cross-Sectional Study. Urol Int 2015; 95:50-5. [PMID: 25926099 DOI: 10.1159/000366007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/15/2014] [Indexed: 11/19/2022]
Abstract
AIMS To estimate efficacy and treatment satisfaction with tamsulosin 0.2 mg in patients with symptomatic bladder outlet obstruction secondary to benign prostatic enlargement and lower urinary tract symptoms in relation to personal satisfaction. METHODS The study was conducted in 1,260 subjects who were asked to fill in detailed questionnaires designed to evaluate their satisfaction with the treatment and symptom improvement 8 weeks after receiving tamsulosin 0.2 mg. RESULTS After being treated with tamsulosin 0.2 mg for 8 weeks, the International Prostate Symptom Score (IPSS) score improved significantly. Among the 1,260 patients, 813 (64.52%) were satisfied, while 447 (35.48%) were dissatisfied with tamsulosin 0.2 mg. The reasons for patient dissatisfaction were efficacy problems (79.87%) and side effects (4.25%). Treatment satisfaction was affected by age, underlying medical disease and baseline IPSS severity (p = 0.020, 0.0427 and <0.001, respectively), but only age and baseline IPSS were risk factors for dissatisfaction. CONCLUSIONS Tamsulosin 0.2 mg was effective in symptomatic improvement, but a relatively high proportion of patients were dissatisfied with the treatment. Efficacy problems were selected by patients as the main reason for dissatisfaction. It is also significant to note that the degree of satisfaction was related to age and baseline IPSS severity.
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Affiliation(s)
- Hoon Choi
- Department of Urology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea
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Abstract
PURPOSE OF REVIEW α1-Adrenoceptor blockers are the most frequently prescribed medical therapy in the treatment of lower urinary tract symptom suggestive of benign prostatic hyperplasia (LUTS/BPH). The purpose of this review is to highlight the evolution of adrenoceptor blockers with emphasis on newly approved drugs. RECENT FINDINGS Over the past years new formulations of several α1-adrenoceptor blockers were introduced to the market. Five long-acting α1-blockers are currently approved by the Food and Drug Administration for treatment of symptomatic LUTS/BPH: terazosin, doxazosin, tamsulosin, alfuzosin and silodosin. Silodosin is the only adrenoceptor blocker that exhibits true selectivity for the α1-adrenoceptor subtypes. This unique adrenoceptor selectivity profile likely accounts for the very favorable cardiovascular safety profile. SUMMARY Tamsulosin, alfuzosin slow release and silodosin do not require dose titration. Alfuzosin, terazosin, doxazosin and silodosin have all been shown to be effective in relieving LUTS/BPH independent of prostate size. Low incidence of orthostatic hypotension has been reported for silodosin, but abnormal ejaculation is the most commonly reported adverse effect.
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Abstract
BACKGROUND Acute ureteric colic is commonly associated with severe and debilitating pain. Theoretically, increasing fluid flow through the affected kidney might expedite stone passage, thereby improving symptoms more quickly. The efficacy and safety of interventions such as high volume intravenous (IV) or oral fluids and diuretics aimed at expediting ureteric stone passage is, however, uncertain. OBJECTIVES To look at the benefits and harms of diuretics and high volume (above maintenance) IV or oral fluid therapy for treating adult patients presenting with uncomplicated acute ureteric colic. SEARCH METHODS We searched the Cochrane Renal Group's specialised register (3 January 2012). Previously we searched the Cochrane Central Register of Controlled Trials (CENTRAL The Cochrane Library), MEDLINE (from 1966), EMBASE (from 1980) and handsearched reference lists of nephrology and urology textbooks, review articles, relevant studies, and abstracts from nephrology scientific meetings. SELECTION CRITERIA All randomised controlled trials (RCTs) and quasi-RCTs (including the first period of randomised cross-over studies) looking at diuretics or high volume IV or oral fluids for treating uncomplicated acute ureteric colic in adult patients presenting to the emergency department for the first time during that episode were included. DATA COLLECTION AND ANALYSIS Two authors independently assessed study quality and extracted data. Statistical analyses were performed using the random-effects model for multiple studies of the same outcomes, otherwise the fixed-effect model was used. Results were expressed as risk ratios (RR) for dichotomous outcomes or as mean differences (MD) for continuous data with 95% confidence intervals (CI). MAIN RESULTS Two studies (enrolling 118 participants) examined the association between intense hydration and ureteric colic outcomes. There was no significant difference in pain at six hours (1 study, 60 participants: RR 1.06, 95% CI 0.71 to 1.57), surgical stone removal (1 study, 60 participants: RR 1.20, 95% CI 0.41 to 3.51) or manipulation by cystoscopy (1 study, 60 participants: RR 0.67, 95% CI 0.21 to 2.13) when no fluids over six hours was compared to three litres IV fluids administered over a six hour period. There was no difference in stone clearance (1 study 43 participants: RR 1.38, 95% CI 0.50 to 3.84), hourly pain score or patients' narcotic requirements (P > 0.05 for all comparisons) when forced IV hydration of two litres over four hours was compared with minimal IV hydration at 20 mL/hour.One study did not provide any details which would have allowed us to assess any of the risk of bias items (selection, detection, performance, attrition or reporting bias). The second study did not report the method of randomisation or allocation (selection bias - unclear), they reported that the patients were blinded to therapy (low risk of bias), analgesics were administered according to predetermined pain score criteria (low risk), and assessment of stone passage was unlikely to have been biased by knowledge of group assignment (low risk). However the second study also reported a high percentage of participants excluded post randomisation (26%; high risk of bias). We were unable to assess or ascertain any of the other risk of bias items. AUTHORS' CONCLUSIONS We found no reliable evidence in the literature to support the use of diuretics and high volume fluid therapy for people with acute ureteric colic. However, given the potential positive therapeutic impact of fluids and diuretics to facilitate stone passage, the capacity of these interventions warrants further investigation to determine safety and efficacy profiles.
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Affiliation(s)
- Andrew S Worster
- Division of Emergency Medicine, Department of Medicine, McMaster University, 237 Barton East, Rm. 250a McMaster Clinic, Hamilton, Ontario, Canada, L8L 2X2
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Lojanapiwat B, Permpongkosol S. The efficacy and safety of oral Tamsulosin controlled absorption system (OCAS) for the treatment of lower urinary tract symptoms due to bladder outlet obstruction associated with benign prostatic hyperplasia: an open-label preliminary study. Int Braz J Urol 2011; 37:468-76. [DOI: 10.1590/s1677-55382011000400005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2010] [Indexed: 11/21/2022] Open
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Neill MG, Shahani R, Zlotta AR. Tamsulosin oral controlled absorption system (OCAS) in the treatment of benign prostatic hypertrophy. Ther Clin Risk Manag 2011; 4:11-8. [PMID: 18728700 PMCID: PMC2503646 DOI: 10.2147/tcrm.s86] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The efficacy of tamsulosin at the cost of a relatively benign side effect profile has been attributed to receptor selectivity directed at the α1a and α1d adrenergic receptor subtypes. The oral-controlled absorption system (OCAS®) represents a drug delivery refinement that incorporates a matrix of gel-forming and gel-enhancing agents to promote a constant drug release independent of environmental food or fluid. There are clinical data to support the concept that drug peaks are lessened and that drug release continues throughout the alimentary tract due to the OCAS formulation. Furthermore this equates with less adverse effects on physiologic parameters. To date however improvements in cardiovascular symptoms such as dizziness, headache and syncope have not been demonstrated in healthy men. Ejaculatory dysfunction appears less problematic with the OCAS preparation. Tamsulosin OCAS may be of greatest benefit to men with cardiovascular co-morbidities taking anti-hypertensive medications that might predispose them to symptomatic hypotensive episodes. It will be necessary to evaluate this group of men more closely in further trials to determine what they stand to gain from changing medications, and then relate this to drug costs to draw a final conclusion as to the place of tamsulosin OCAS in contemporary urological practice.
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Affiliation(s)
- Mischel G Neill
- Division of Urology, Department of Surgical Oncology, Princess Margaret and Mount Sinai Hospitals, University of Toronto Toronto, Canada
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Abstract
α(1)-Adrenoceptors have been identified and characterized extensively by functional, radioligand-binding, and molecular biological techniques. Molecular clones have been isolated for three α(1)-subtypes (α(1a), α(1b), and α(1d)), and these subtypes are also functionally characterized. α(1)-Adrenoceptors are present in the prostate, urethra, bladder (urothelium, smooth muscle, and afferent nerves), ureter, vas deferens, peripheral ganglia, nerve terminals, vascular tissues, and central nervous system (CNS), and they could all potentially influence overall urinary function and contribute to both the therapeutic and adverse effects of α(1)-adrenoceptor antagonists in patients with benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS). This review aimed to discuss the relevant physiological and pharmacological roles and molecular biology of α(1)-adrenoceptor subtypes in the prostate, urethra, bladder, ureter, and CNS.
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Cantrell MA, Bream-Rouwenhorst HR, Hemerson P, Magera JS. Silodosin for benign prostatic hyperplasia. Ann Pharmacother 2010; 44:302-10. [PMID: 20071497 DOI: 10.1345/aph.1m320] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To review the pharmacology, pharmacokinetics, clinical trials, and safety of silodosin, a recently approved alpha(1A)-adrenergic receptor (AR) antagonist for benign prostatic hyperplasia (BPH). DATA SOURCES English-only articles obtained from MEDLINE (1966-October 2009) using the search terms silodosin and KMD-3213 were reviewed. In addition, a search of International Pharmaceutical Abstracts (1970-October 2009) was conducted. STUDY SELECTION AND DATA EXTRACTION Available English-language articles were reviewed, as well as abstracts from available non-English articles. DATA SYNTHESIS Silodosin reduces urinary symptoms associated with BPH in as little as 1 day after initiation. The largest clinical trial conducted to date demonstrated a decrease in International Prostate Symptom Score of -6.4 +/- 6.63 points compared to -3.5 +/- 5.84 in patients receiving placebo (p < 0.0001). Silodosin also improved urinary flow rates by approximately 2.8 +/- 3.44 mL/sec, which is comparable to other alpha(1)-AR antagonists. The usual dose of silodosin is 8 mg once daily and should be reduced to 4 mg for patients with moderate renal dysfunction. Use is contraindicated in patients with severe renal and hepatic impairment or taking strong CYP3A4 inhibitors. In clinical trials, the most prevalent adverse effects were ejaculatory disturbances, occurring in approximately 28% of patients, although only 2.8% of patients discontinued treatment due to this adverse effect. Preliminary data suggest that, similar to other third-generation alpha(1A)-AR antagonists, silodosin has little potential to cause significant cardiovascular adverse effects such as orthostatic hypotension or syncope. To confirm these findings, long-term studies are still needed, especially in patients taking antihypertensive agents and in those with a history of intolerance to other alpha(1)-AR antagonists. CONCLUSIONS Silodosin was approved by the Food and Drug Administration in 2008. Long-term studies demonstrating improvement in clinically important outcomes of BPH have yet to be published. In addition, pharmacoeconomic analyses would assist in defining its current place in therapy. Until this information is available, silodosin may be best reserved as an alternative to other second- and third-generation alpha(1)-AR antagonists.
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Affiliation(s)
- Matthew A Cantrell
- College of Pharmacy, University of Iowa; Clinical Pharmacy Specialist, Veterans Affairs Medical Center, Iowa City, IA, USA.
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Okutsu H, Matsumoto S, Hanai T, Noguchi Y, Fujiyasu N, Ohtake A, Suzuki M, Sato S, Sasamata M, Uemura H, Kurita T. Effects of tamsulosin on bladder blood flow and bladder function in rats with bladder outlet obstruction. Urology 2009; 75:235-40. [PMID: 19647304 DOI: 10.1016/j.urology.2009.05.045] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 04/14/2009] [Accepted: 05/20/2009] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To investigate the mechanism underlying the ameliorating effect of tamsulosin, an alpha(1)-adrenoceptor antagonist, on storage symptoms associated with benign prostatic hyperplasia, the effects of tamsulosin on bladder blood flow (BBF) and bladder function was evaluated in rats with bladder outlet obstruction (BOO). METHODS BOO was produced by partial ligature of the proximal urethra, which was maintained for 2 weeks. Tamsulosin was subcutaneously administered via an osmotic pump for 2 weeks immediately after the BOO surgery. The BBF in the sham-operated rats, the control BOO rats, and the tamsulosin-treated BOO rats was measured using the fluoromicrosphere method. Each rat was kept in a metabolic cage for observation of micturition behavior. Expression of the alpha(1)-adrenoceptor subtype mRNA in the vesical artery was measured by reverse transcriptase-polymerase chain reaction. RESULTS BBF was significantly reduced in BOO rats compared with sham-operated rats, and tamsulosin significantly increased the BBF in BOO rats. Tamsulosin ameliorated the decrease in mean voided volume in BOO rats with bladder masses < 500 mg. Expression of the alpha(1)-adrenoceptor subtype in the vesical artery was alpha(1a)- > alpha(1d)-adrenoceptors; almost no expression was observed of alpha(1b)-adrenoceptors in either sham-operated or BOO rats. CONCLUSIONS Tamsulosin increased BBF in BOO rats via an antagonistic effect, presumably on the alpha(1A)- and/or alpha(1D)-adrenoceptor in the vesical artery mainly, and improved the decrease in mean voided volume. Therefore, the results of this study suggest that tamsulosin improves bladder overactivity via improvement of BBF.
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Affiliation(s)
- Hiroko Okutsu
- Applied Pharmacology Research Laboratories, Astellas Pharma Inc, Miyukigaoka, Tsukuba-shi, Ibaraki, Japan
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Nanda K, Naruganahalli KS, Gupta S, Malhotra S, Tiwari A, Hegde LG, Jain S, Sinha N, Gupta JB, Chugh A, Anand N, Ray A. RBx 6198: A novel α1-adrenoceptor antagonist for the treatment of benign prostatic hyperplasia. Eur J Pharmacol 2009; 607:213-9. [DOI: 10.1016/j.ejphar.2009.02.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 02/02/2009] [Accepted: 02/09/2009] [Indexed: 10/21/2022]
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Subtypes of alpha1-adrenoceptors in BPH: future prospects for personalized medicine. ACTA ACUST UNITED AC 2009; 6:44-53. [PMID: 19132005 DOI: 10.1038/ncpuro1276] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 11/14/2008] [Indexed: 12/18/2022]
Abstract
The alpha(1)-adrenoceptors (alpha(1)-ARs) are involved in regulation of prostatic smooth muscle tone, and are a critical mediator of lower urinary tract symptoms and pathophysiology in benign prostatic hyperplasia (BPH). As a result, alpha(1)-AR antagonists are now used as first-line medical treatment for BPH. Three alpha(1)-AR subtypes (alpha(1a)-AR, alpha(1b)-AR, alpha(1d)-AR) have been identified on the basis of results of pharmacological and molecular cloning studies; however, the precise physiological role of individual alpha(1)-AR subtypes remains elusive. The expression levels of alpha(1)-AR subtypes in the prostate differ between patients, and individual differences in the genetic background of patients with BPH might be associated with variation in responses to subtype-selective alpha(1)-AR antagonists. In addition, single nucleotide polymorphism and microarray-based gene expression profiling studies might provide an opportunity to identify markers that predict clinical response and therapeutic tolerance to alpha(1)-AR antagonists. Further genomic studies will refine our knowledge of the functions of alpha(1)-AR subtypes, lead to new strategies for the clinical management of BPH and, perhaps, enable personalized treatment of BPH in the future.
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Kobayashi S, Tomiyama Y, Maruyama K, Hoyano Y, Yamazaki Y, Kusama H. Effects of four different .ALPHA.1-adrenoceptor antagonists on .ALPHA.-adrenoceptor agonist-induced contractions in isolated mouse and hamster ureters. J Smooth Muscle Res 2009; 45:187-95. [DOI: 10.1540/jsmr.45.187] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Shinya Kobayashi
- Pharmacology, Research and Development, Kissei Pharmaceutical Co. Ltd
| | | | - Kazuyasu Maruyama
- Pharmacology, Research and Development, Kissei Pharmaceutical Co. Ltd
| | - Yuji Hoyano
- Pharmacology, Research and Development, Kissei Pharmaceutical Co. Ltd
| | | | - Hiroshi Kusama
- Pharmacology, Research and Development, Kissei Pharmaceutical Co. Ltd
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Oger S, Behr-Roussel D, Gorny D, Charles Tremeaux J, Combes M, Alexandre L, Giuliano F. Combination of alfuzosin and tadalafil exerts in vitro an additive relaxant effect on human corpus cavernosum. J Sex Med 2008; 5:935-945. [PMID: 18221277 DOI: 10.1111/j.1743-6109.2007.00754.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION Phosphodiesterase type 5 (PDE5) inhibitors, such as tadalafil, are a first-line treatment for erectile dysfunction (ED). Nevertheless, some patients do not respond to this treatment. Clinical data suggest that the addition of alpha1-adrenoceptor blocker, such as alfuzosin, commonly prescribed for lower urinary tract symptoms suggestive of benign prostatic hyperplasia, may be of benefit. Aim. Evaluation of the effect of alfuzosin, tadalafil or the combination of both on human corpus cavernosum. METHODS Human cavernosal tissues were obtained from 10 patients undergoing penile surgery. Strips contractility was studied in organ baths. Concentration-response curves to tadalafil were generated on norepinephrine (NE, 1-10 microM)-precontracted strips in the presence of alfuzosin or vehicle. Frequency-response curves (FRC) to electrical field stimulation (EFS, 0-64 Hz, 3 ms, 10 seconds, 300 mA) were generated in the presence of vehicle, alfuzosin, tadalafil, or both drugs combined. EFS (20 Hz, 1 ms, 10 seconds, 300 mM)-induced nitrergic relaxation on NE-precontracted strips was studied in the presence of vehicle, alfuzosin, tadalafil, or both drugs combined. MAIN OUTCOME MEASURES Functional measurement of cavernosal smooth muscle relaxation in the presence of tadalafil and alfuzosin. RESULTS The relaxation induced by tadalafil (10(-10) to 10(-5) M) on precontracted strips was enhanced by alfuzosin at both 10(-8) and 10(-7) M. The combination of alfuzosin (3.10(-8) M) and tadalafil (10(-7) M) was more efficient to inhibit FRC-induced contractions than each compound alone. The combination of tadalafil (10(-6) M) and alfuzosin (10(-8) M) increased the relaxation induced by EFS and its effect was greater than tadalafil alone. In addition, the combination of tadalafil (10(-6) M) and alfuzosin (10(-7) M) prolonged EFS-induced relaxation to a greater extent than each compound alone. CONCLUSIONS In vitro, the combination of alfuzosin and tadalafil is more efficient than each compound alone to relax adrenergic tone or to enhance nitrergic relaxation of the human corpus cavernosum. Such a combination deserves further investigation in placebo-controlled studies to evaluate its benefit in ED patients who are not sufficiently improved by PDE5 inhibitors.
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Affiliation(s)
| | | | | | | | | | | | - François Giuliano
- Raymond Poincaré Hospital-Department of Physical Medicine and Rehabilitation, Garches, France.
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Ballou LM, Selinger ES, Choi JY, Drueckhammer DG, Lin RZ. Inhibition of mammalian target of rapamycin signaling by 2-(morpholin-1-yl)pyrimido[2,1-alpha]isoquinolin-4-one. J Biol Chem 2007; 282:24463-70. [PMID: 17562705 DOI: 10.1074/jbc.m704741200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Signaling through the mammalian target of rapamycin (mTOR) is hyperactivated in many human tumors, including hamartomas associated with tuberous sclerosis complex (TSC). Several small molecules such as LY294002 inhibit mTOR kinase activity, but they also inhibit phosphatidylinositol 3-kinase (PI3K) at similar concentrations. Compound 401 is a synthetic inhibitor of DNA-dependent protein kinase (DNA-PK) that also targets mTOR but not PI3K in vitro (Griffin, R. J., Fontana, G., Golding, B. T., Guiard, S., Hardcastle, I. R., Leahy, J. J., Martin, N., Richardson, C., Rigoreau, L., Stockley, M., and Smith, G. C. (2005) J. Med. Chem. 48, 569-585). We used 401 to test the cellular effect of mTOR inhibition without the complicating side effects on PI3K. Treatment of cells with 401 blocked the phosphorylation of sites modified by mTOR-Raptor and mTOR-Rictor complexes (ribosomal protein S6 kinase 1 Thr(389) and Akt Ser(473), respectively). By contrast, there was no direct inhibition of Akt Thr(308) phosphorylation, which is dependent on PI3K. Similar effects were also observed in cells that lack DNA-PK. The proliferation of TSC1-/- fibroblasts was inhibited in the presence of 401, but TSC1+/+ cells were resistant. In contrast to rapamycin, long-term treatment of TSC1-/- cells with 401 did not up-regulate phospho-Akt Ser(473). Because increased Akt activity promotes survival, this may explain why the level of apoptosis was increased in the presence of 401 but not rapamycin. These results suggest that mTOR kinase inhibitors might be more effective than rapamycins in controlling the growth of TSC hamartomas and other tumors that depend on elevated mTOR activity.
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Affiliation(s)
- Lisa M Ballou
- Department of Medicine, Stony Brook University, Stony Brook, New York 11794, USA.
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Lepor H. Alpha blockers for the treatment of benign prostatic hyperplasia. Rev Urol 2007; 9:181-190. [PMID: 18231614 PMCID: PMC2213889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The evolution of alpha blocker therapy for benign prostatic hyperplasia (BPH) has focused on improving convenience and tolerability. Indications for treating BPH include reversing signs and symptoms or preventing progression of the disease. The indication that most commonly drives the need for intervention is relief of lower urinary tract symptoms (LUTS) with the intent of improving quality of life. Alpha blockers are the most effective, least costly, and best tolerated of the drugs for relieving LUTS. Four long-acting alpha 1 blockers are approved by the Food and Drug Administration for treatment of symptomatic LUTS/BPH: terazosin, doxazosin, tamsulosin, and alfuzosin. All are well tolerated and have comparable dose-dependent effectiveness. Tamsulosin and alfuzosin SR do not require dose titration. Alfuzosin, terazosin, and doxazosin have all been shown to be effective in relieving LUTS/BPH independent of prostate size.
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Affiliation(s)
- Herbert Lepor
- Department of Urology, New York University School of Medicine New York, NY
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Michel MC, Vrydag W. Alpha1-, alpha2- and beta-adrenoceptors in the urinary bladder, urethra and prostate. Br J Pharmacol 2006; 147 Suppl 2:S88-119. [PMID: 16465187 PMCID: PMC1751487 DOI: 10.1038/sj.bjp.0706619] [Citation(s) in RCA: 338] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1 We have systematically reviewed the presence, functional responses and regulation of alpha(1)-, alpha(2)- and beta-adrenoceptors in the bladder, urethra and prostate, with special emphasis on human tissues and receptor subtypes. 2 Alpha(1)-adrenoceptors are only poorly expressed and play a limited functional role in the detrusor. Alpha(1)-adrenoceptors, particularly their alpha(1A)-subtype, show a more pronounced expression and promote contraction of the bladder neck, urethra and prostate to enhance bladder outlet resistance, particularly in elderly men with enlarged prostates. Alpha(1)-adrenoceptor agonists are important in the treatment of symptoms of benign prostatic hyperplasia, but their beneficial effects may involve receptors within and outside the prostate. 3 Alpha(2)-adrenoceptors, mainly their alpha(2A)-subtype, are expressed in bladder, urethra and prostate. They mediate pre-junctional inhibition of neurotransmitter release and also a weak contractile effect in the urethra of some species, but not humans. Their overall post-junctional function in the lower urinary tract remains largely unclear. 4 Beta-adrenoceptors mediate relaxation of smooth muscle in the bladder, urethra and prostate. The available tools have limited the unequivocal identification of receptor subtypes at the protein and functional levels, but it appears that the beta(3)- and beta(2)-subtypes are important in the human bladder and urethra, respectively. Beta(3)-adrenoceptor agonists are promising drug candidates for the treatment of the overactive bladder. 5 We propose that the overall function of adrenoceptors in the lower urinary tract is to promote urinary continence. Further elucidation of the functional roles of their subtypes will help a better understanding of voiding dysfunction and its treatment.
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MESH Headings
- Adrenergic Agonists/pharmacology
- Animals
- Gene Expression Regulation
- Humans
- Male
- Muscle Contraction
- Muscle, Smooth/metabolism
- Prostate/drug effects
- Prostate/metabolism
- Receptors, Adrenergic/drug effects
- Receptors, Adrenergic/genetics
- Receptors, Adrenergic/metabolism
- Receptors, Adrenergic, alpha-1/metabolism
- Receptors, Adrenergic, alpha-2/metabolism
- Receptors, Adrenergic, beta/metabolism
- Urethra/drug effects
- Urethra/metabolism
- Urinary Bladder/drug effects
- Urinary Bladder/metabolism
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Affiliation(s)
- Martin C Michel
- Department of Pharmacology & Pharmacotherapy, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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Ohtake A, Ukai M, Saitoh C, Sonoda R, Noguchi Y, Okutsu H, Yuyama H, Sato S, Sasamata M, Miyata K. Effect of tamsulosin on spontaneous bladder contraction in conscious rats with bladder outlet obstruction: Comparison with effect on intraurethral pressure. Eur J Pharmacol 2006; 545:185-91. [PMID: 16887117 DOI: 10.1016/j.ejphar.2006.06.054] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Revised: 03/09/2006] [Accepted: 06/20/2006] [Indexed: 11/30/2022]
Abstract
We investigated the effect of tamsulosin, an alpha(1)-adrenoceptor antagonist, on bladder function, especially spontaneous bladder contractions before micturition (premicturition contraction), in conscious rats with bladder outlet obstruction induced by partial urethral ligation, and compared the results with the effect on intraurethral pressure response in anesthetized rats. In obstructed rats, the alpha(1)-adrenoceptor antagonists tamsulosin, naftopidil and urapidil and non-selective alpha-adrenoceptor antagonist phentolamine inhibited premicturition contractions in a dose-dependent fashion. In contrast, yohimbine, an alpha(2)-adrenoceptor antagonist, and atropine, a muscarinic receptor antagonist, hardly inhibited them. Tamsulosin and urapidil showed clearly inhibitory effects on increases in intraurethral pressure induced by phenylephrine, an alpha(1)-adrenoceptor agonist, in the same dose range as that at which they inhibited premicturition contractions, whereas naftopidil required somewhat higher doses to inhibit increases in intraurethral pressure than those at which it inhibited premicturition contractions. In conclusion, premicturition contractions observed in obstructed rats were sensitive to alpha(1)-adrenoceptor antagonists, but not to alpha(2)-adrenoceptor or muscarinic receptor antagonists. Tamsulosin was shown to be effective against both premicturition contraction and intraurethral pressure response in the same dose range in rats. These results partly support the fact that tamsulosin has improved storage symptoms as well as voiding symptoms in patients with lower urinary tract symptoms associated with bladder outlet obstruction by blocking alpha(1)-adrenoceptors.
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Affiliation(s)
- Akiyoshi Ohtake
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki, 305-8585, Japan.
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Settas G, Fitt AW. Intraoperative floppy iris syndrome in a patient taking alfuzosin for benign prostatic hypertrophy. Eye (Lond) 2006; 20:1431-2. [PMID: 16498436 DOI: 10.1038/sj.eye.6702291] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Lepor H. The evolution of alpha-blockers for the treatment of benign prostatic hyperplasia. Rev Urol 2006; 8 Suppl 4:S3-9. [PMID: 17215999 PMCID: PMC1765042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Alpha-blockers have been evaluated for the treatment of benign prostatic hyperplasia (BPH) for 30 years, from early trials with the nonselective alpha-inhibitor phenoxybenzamine to short-acting (prazosin) then long-acting (terazosin, doxazosin, tamsulosin, alfuzosin) selective alpha(1)-antagonists. All of the alpha-blockers evaluated have demonstrated comparable effectiveness, and the evolution of alpha-blocker therapy for BPH has therefore focused primarily on improving convenience and tolerability. Although all of the long-acting alpha(1)-blockers are well tolerated, only tamsulosin and alfuzosin SR are administered without the requirement for dose titration. Alfuzosin has the additional advantage over tamsulosin of a lower incidence of ejaculatory dysfunction. Studies of subtype-selective alpha(1)-antagonists have not demonstrated superior efficacy or improved tolerability over the existing long-acting alpha(1)-blockers.
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Affiliation(s)
- Herbert Lepor
- Department of Urology, New York University School of Medicine New York, NY
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Garg G, Singh D, Saraf S, Saraf S. Management of Benign Prostate Hyperplasia: An Overview of α-Adrenergic Antagonist. Biol Pharm Bull 2006; 29:1554-8. [PMID: 16880603 DOI: 10.1248/bpb.29.1554] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Benign prostate hyperplasia (BPH) is common among above 50 years age group, interfere with normal activities of lower urinary tract function and reduce the sense of well being. It can also be progressive, with a lost of urinary retention, bladder infection, bladder calculus and renal failure. Although many men with mild to moderate symptoms to well without therapy, others have gradually increasing symptoms and require medical therapy or surgery. BPH is the non-malignant, uncontrolled growth of cells in the prostate gland. This cell growth usually occurs in the tissue that surrounds the urethra as it passes through the prostate gland to the bladder. As BPH progresses, the gland constricts the urethra and obstructs the urine outflow. The bladder no longer empties completely, creating an environment in which infections, bladder stones, and chronic prostatities may develop. If left untreated, chronic obstruction can lead to the back up of urine into the ureters and compromise kidney function. In hyperplastic prostate tissue, the prostate capsule, and the bladder neck are blocked, by using alpha-adrenergic antagonist drugs; the smooth muscle tone of these structures is decreased. As a result, resistance to urinary flow through the bladder neck and the prostatic urethra decreases and urinary flow increases. A variety of alpha-adrenergic antagonists with distinct properties have been investigated as possible treatments for benign prostate hyperplasia.
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Affiliation(s)
- Gopal Garg
- Institute of Pharmacy, Pt. Ravishankar Shukla University, India.
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Hieble JP, Ruffolo RR. Recent advances in the identification of a 1- and a 2-adrenoceptor subtypes: therapeutic implications. Expert Opin Investig Drugs 2005; 6:367-87. [PMID: 15989605 DOI: 10.1517/13543784.6.4.367] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The cloning of multiple subtypes of both alpha1- and alpha2-adrenoceptors has renewed interest in the therapeutic application of agents interacting with these receptors. Effort has primarily been directed towards the design of uroselective alpha1-adrenoceptor antagonists for the treatment of benign prostatic hyperplasia (BPH). Evidence is accumulating for the involvement of a novel alpha1-adrenoceptor, designated as alpha1L-adrenoceptor, in alpha1-adrenoceptor-mediated smooth muscle contraction in prostatic and other urogenital tissues. While several antagonists showing a high degree of uroselectivity in animal models have been identified, their clinical superiority over the currently available alpha1-adrenoceptor antagonists has not yet been demonstrated. It is possible that the interaction with alpha1-adrenoceptors, as yet uncharacterised subtypes, at non-prostatic sites contributes to the therapeutic activity of this drug class in BPH. The alpha1-adrenoceptor subtypes involved in the control of vascular tone are currently being evaluated, and the profile of interaction with the various alpha1-adrenoceptor subtypes may play a key role in the efficacy of cardiovascular drugs such as carvedilol. Alpha2-adrenoceptor agonists are now being employed for a variety of therapeutic applications, most involving actions on receptors within the central nervous system (CNS). These agents are useful in the treatment of hypertension, glaucoma, opiate withdrawal and attention deficit hyperactivity disorder (ADHD), and as analgesics and adjuncts to general anaesthesia. While subtype selectivity has not yet been applied to the design of new alpha2-adrenoceptor agonists for these applications, recent gene mutation/knock-out experiments have identified the alpha2-subtypes involved in some of these actions, and optimisation of a therapeutic profile may be possible. Furthermore, the design of agents combining affinities for multiple adrenoceptor subtypes, or the combination of a specific adrenoceptor affinity profile with another pharmacological action, may offer advantages over molecules selective for an individual adrenoceptor subtype.
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Affiliation(s)
- J P Hieble
- Division of Pharmacological Sciences, SmithKline Beecham Pharmaceuticals, 709 Swedeland Road, King of Prussia, PA 19406, USA
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Kaplan SA. alpha-Blocker Therapy: Current Update. Rev Urol 2005; 7 Suppl 8:S34-42. [PMID: 16985889 PMCID: PMC1477635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
alpha-Blockade is the predominant form of medical therapy for the treatment of symptomatic bladder outlet obstruction due to benign prostatic hyperplasia (BPH). Recent research has shown that there is a series of alpha(1) receptor subtypes present in humans and that the alpha(1A) subtype appears to play a primary role in mediating prostatic smooth muscle contraction. Recent interest has therefore focussed on the development of agents specific to this alpha(1A) receptor subtype. The approval by the Food and Drug Administration of tamsulosin, an alpha(1A)-specific antagonist, offers physicians in the United States the opportunity to prescribe a selective alpha(1)-blocker for the treatment of BPH. Tamsulosin offers a pharmacologic means to better target alpha-blockade specifically to the prostatic smooth muscle and spare the vascular smooth muscle. Use of this agent has resulted in a lower incidence of clinically relevant effects on blood pressure or heart rate and minimal cardiovascular adverse effects.
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Lowe FC. Role of the newer alpha, -adrenergic-receptor antagonistsin the treatment of benign prostatic hyperplasia-related lower urinary tract symptoms. Clin Ther 2004; 26:1701-13. [PMID: 15639685 DOI: 10.1016/j.clinthera.2004.11.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND Although initially introduced for the management of hypertension, alpha(1)-adrenergic-receptor antagonists (alpha1-blockers) have become the standard of care for the medical management of benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTS). However, these agents have the potential to produce orthostatic hypotension and other blood pressure-related adverse effects in normotensive patients and in those receiving concurrent treatment with other antihypertensive agents. As a result, more "uroselective," less vasoactive alpha(1)-blockers have been developed. OBJECTIVE This article reviews current information on the role of alpha(1)-blockers in the treatment of BPH-related LUTS. The focus is on tamsulosin and alfuzosin, newer "uroselective" agents in this class that have a decreased potential for cardiovascular adverse effects. METHODS Relevant articles were identified through a search of the English-language literature indexed on MEDLINE and the proceedings of scientific meetings from 1976 to 2003. The search terms were benign prostatic hyperplasia treatment, alpha(1)-adrenergic-receptor blocker, uroselectivity, lower urinary tract symptoms, complications, and cardiovascular. RESULTS Tamsulosin has selectivity for the a alpha(1) and alpha(1d) receptor subtypes. Alfuzosin, although not receptor subtype selective, is clinically "uroselective" and does not significantly affect vascular alpha-adrenergic receptors. Both agents are efficacious in relieving LUTS and have a decreased potential for such cardiovascular adverse effects as postural hypotension. Common adverse events with these agents include dizziness and asthenia. CONCLUSION Based on the available data, "uroselective" alpha(1)-blockers should be considered over older, more vasoactive agents for the medical management of LUTS, particularly in patients with BPH and hypertension.
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Affiliation(s)
- Franklin C Lowe
- Department of Urology, Columbia University College of Physicians and Surgeons, St. Luke's-Roosevelt Hospital Center, 425 West 59th Street, Suite 3A, New York, NY 10019, USA.
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Tambaro S, Ruiu S, Dessi C, Mongeau R, Marchese G, Pani L. Evaluation of tamsulosin and alfuzosin activity in the rat vas deferens: relevance to ejaculation delays. J Pharmacol Exp Ther 2004; 312:710-7. [PMID: 15470085 DOI: 10.1124/jpet.104.074740] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effect of two alpha-adrenergic receptor antagonists widely employed in the therapy of benign prostatic hyperplasia, tamsulosin [(-)-(R)-5-[2-[[2-(0-ethoxyphenoxy) ethyl]amino]propyl]-2-methoxybenzenesulfonamide] and alfuzosin [(+/-)-N-[3-[(4-amino-6,7-dimethoxy-2-quinazolinyl) methylamino]propyl] tetrahydro-2-furancarboxamide], was investigated in the rat vas deferens. Because several clinical studies have shown that tamsulosin causes ejaculatory disorders, this study also evaluated the possible mechanisms implicated in these disorders by comparing the effect of tamsulosin with that of alfuzosin. Tamsulosin competitively antagonized the contractions induced by noradrenaline in vitro in the epididymal portion of the vas deferens with a potency pA(2) value of 9.2 +/- 0.8. In the prostatic portion, tamsulosin increased the amplitude of intermittent spikes induced by exogenous noradrenaline (100-1000 microM). In both portions of the vas deferens, alfuzosin behaved as an alpha-adrenergic antagonist blocking the contractions induced by exogenous noradrenaline without altering spikes. The administration of tamsulosin (3 microg/kg i.v.) significantly reduced the contractions evoked by electrical pulses in the epididymal portion, whereas it increased those produced in the prostatic portion. Intravenous tamsulosin antagonized the contraction produced by exogenous noradrenaline, whereas alfuzosin administration (10 microg/kg i.v.) did not change the electrically induced contractions in both portions of the rat vas deferens and did not antagonize the contractions produced by exogenous noradrenaline. The fact that tamsulosin unusually enhances noradrenaline-induced intermittent spike contractions and nerve stimulation-induced twitches in the prostatic portions might be linked to its greater propensity to cause sexual dysfunctions.
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Affiliation(s)
- Simone Tambaro
- Neuroscienze PharmaNess Scarl, Via Palabanda 9, 09124 Calgliari, Italy
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Jähnichen S, Eltze M, Pertz HH. Evidence that α1B-adrenoceptors are involved in noradrenaline-induced contractions of rat tail artery. Eur J Pharmacol 2004; 488:157-67. [PMID: 15044047 DOI: 10.1016/j.ejphar.2004.02.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2003] [Revised: 02/05/2004] [Accepted: 02/10/2004] [Indexed: 10/26/2022]
Abstract
The present study characterizes the alpha(1)-adrenoceptor subtypes mediating contractions to noradrenaline in isolated ring preparations of rat tail artery. Concentration-response (E/[A]) curves to noradrenaline were apparently monophasic (pEC(50) 6.47) but became biphasic in the presence of the selective alpha(1A)-adrenoceptor antagonist (+/-)-1,3,5-trimethyl-6-[[3-[4-((2,3-dihydro-2-hydroxymethyl)-1,4-benzodioxin-5-yl)-1-piperazinyl]propyl]amino]-2,4(1H,3H)-pyrimidinedione (B8805-033). Whereas the first phase of contraction to noradrenaline remained nearly unaffected in the presence of B8805-033 (0.03-3 microM), the second phase was concentration-dependently shifted to the right (pK(B) 8.06). In the presence of B8805-033 (3 microM), noradrenaline-induced contractions (pEC(50) 6.55) were antagonized in a competitive manner by prazosin (pK(B) 9.24), tamsulosin (pK(B) 8.55), 2-(2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane (WB 4101; pK(B) 7.81), spiperone (pK(B) 7.69), 4-amino-2-[4-[1-(benzyloxycarbonyl)-2(S)-[[(1,1-dimethylethyl)amino]carbonyl]-piperazinyl]-6,7-dimethoxyquinazoline (L-765,314; pK(B) 7.31), 5-methylurapidil (pK(B) 6.55), 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione (BMY 7378; pK(B) 6.43), and 8-[2-(1,4-benzodioxan-2-ylmethylamino)ethyl]-8-azaspiro[4.5]decane-7,9-dione (MDL 73005EF; pK(B) 5.71), and were also antagonized by 100 microM chloroethylclonidine. N-[2-(2-cyclopropylmethoxyphenoxy)ethyl]-5-chloro-alpha,alpha-dimethyl-1H-indole-3-ethanamine (RS-17053) behaved as a noncompetitive antagonist (apparent pA(2) 6.55). Antagonist affinities obtained under these experimental conditions correlated highly with affinities at native and cloned alpha(1B)-adrenoceptors. Pretreatment of arterial rings with B8805-033 (3 microM) followed by receptor inactivation with chloroethylclonidine (100 microM) yielded monophasic E/[A] curves to noradrenaline (pEC(50) 6.14). Noradrenaline-induced contractions were competitively antagonized by tamsulosin (pK(B) 10.32), 5-methylurapidil (pK(B) 8.66), RS-17053 (pK(B) 8.44), B8805-033 (pK(B) 7.87), BMY 7378 (pK(B) 6.54), and L-765,314 (pK(B) 6.41). Antagonist affinities obtained under these experimental conditions correlated highly with affinities at native and cloned alpha(1A)-adrenoceptors. It is concluded that the contraction to noradrenaline in rat tail artery is mediated by both alpha(1B)- and alpha(1A)-adrenoceptors, each component of contraction being separable by use of selective alpha(1A)-adrenoceptor blockade and alpha(1B)-adrenoceptor alkylation, respectively.
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Affiliation(s)
- Sven Jähnichen
- Institute of Pharmacy, Free University of Berlin, Königin-Luise-Str. 2+4, Berlin 14195, Germany
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Ballou LM, Jiang YP, Du G, Frohman MA, Lin RZ. Ca(2+)- and phospholipase D-dependent and -independent pathways activate mTOR signaling. FEBS Lett 2003; 550:51-6. [PMID: 12935885 DOI: 10.1016/s0014-5793(03)00816-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The mammalian target of rapamycin (mTOR) promotes increased protein synthesis required for cell growth. It has been suggested that phosphatidic acid, produced upon activation of phospholipase D (PLD), is a common mediator of growth factor activation of mTOR signaling. We used Rat-1 fibroblasts expressing the alpha(1A) adrenergic receptor to study if this G(q)-coupled receptor uses PLD to regulate mTOR signaling. Phenylephrine (PE) stimulation of the alpha(1A) adrenergic receptor induced mTOR autophosphorylation at Ser2481 and phosphorylation of two mTOR effectors, 4E-BP1 and p70 S6 kinase. These PE-induced phosphorylations were greatly reduced in cells depleted of intracellular Ca(2+). PE activation of PLD was also inhibited in Ca(2+)-depleted cells. Incubation of cells with 1-butanol to inhibit PLD signaling attenuated PE-induced phosphorylation of mTOR, 4E-BP1 and p70 S6 kinase. By contrast, platelet-derived growth factor (PDGF)-induced phosphorylation of these proteins was not blocked by Ca(2+) depletion or 1-butanol treatment. These results suggest that the alpha(1A) adrenergic receptor promotes mTOR signaling via a pathway that requires an increase in intracellular Ca(2+) and activation of PLD. The PDGF receptor, by contrast, appears to activate mTOR by a distinct pathway that does not require Ca(2+) or PLD.
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Affiliation(s)
- Lisa M Ballou
- Department of Medicine, Division of Hematology, Stony Brook University, Stony Brook, NY 11794-8151, USA
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Ballou LM, Lin HY, Fan G, Jiang YP, Lin RZ. Activated G alpha q inhibits p110 alpha phosphatidylinositol 3-kinase and Akt. J Biol Chem 2003; 278:23472-9. [PMID: 12704201 DOI: 10.1074/jbc.m212232200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Some Gq-coupled receptors have been shown to antagonize growth factor activation of phosphatidylinositol 3-kinase (PI3K) and its downstream effector, Akt. We used a constitutively active Galphaq(Q209L) mutant to explore the effects of Galphaq activation on signaling through the PI3K/Akt pathway. Transient expression of Galphaq(Q209L) in Rat-1 fibroblasts inhibited Akt activation induced by platelet-derived growth factor or insulin treatment. Expression of Galphaq(Q209L) also attenuated Akt activation promoted by coexpression of constitutively active PI3K in human embryonic kidney 293 cells. Galphaq(Q209L) had no effect on the activity of an Akt mutant in which the two regulatory phosphorylation sites were changed to acidic amino acids. Inducible expression of Galphaq(Q209L) in a stably transfected 293 cell line caused a decrease in PI3K activity in p110alpha (but not p110beta) immunoprecipitates. Receptor activation of Galphaq also selectively inhibited PI3K activity in p110alpha immunoprecipitates. Active Galphaq still inhibited PI3K/Akt in cells pretreated with the phospholipase C inhibitor U73122. Finally, Galphaq(Q209L) co-immunoprecipitated with the p110alpha-p85alpha PI3K heterodimer from lysates of COS-7 cells expressing these proteins, and incubation of immunoprecipitated Galphaq(Q209L) with purified recombinant p110alpha-p85alpha in vitro led to a decrease in PI3K activity. These results suggest that agonist binding to Gq-coupled receptors blocks Akt activation via the release of active Galphaq subunits that inhibit PI3K. The inhibitory mechanism seems to be independent of phospholipase C activation and might involve an inhibitory interaction between Galphaq and p110alpha PI3K.
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Affiliation(s)
- Lisa M Ballou
- Research Service, Department of Veterans Affairs Medical Center, Northport, New York 11768, USA
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Palea S, Barras M. Comparison of the relaxant effects of alfuzosin, phentolamine and sildenafil on rabbit isolated corpus cavernosum. BJU Int 2003; 91:873-7. [PMID: 12780851 DOI: 10.1046/j.1464-410x.2003.04229.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To compare the direct relaxant effects of alfuzosin, phentolamine and sildenafil in rabbit isolated corpus cavernosum (CC) pre-contracted with phenylephrine or KCl. MATERIALS AND METHODS Penile erectile tissue was obtained from male New Zealand White rabbits (22-26 weeks old). The CC was cut into longitudinal strips and mounted under 2 g resting tension in 5-mL jacketed organ baths containing a modified Krebs solution bubbled with 95% O2, 5% CO2 and maintained at 37 degrees C. Tissue strips were pre-contracted by 60 mmol/L KCl or 10 micro mol/L phenylephrine. After obtaining a stable plateau of contractions, test compounds were added to the organ bath. The relaxant potencies were expressed as the percentage of inhibition of the plateau of contraction induced by 10 micro mol/L phenylephrine. RESULTS Alfuzosin showed a concentration-dependent relaxing effect on rabbit CC pre-contracted by 10 micro mol/L phenylephrine, with a mean (sd) pIC50 of 7.64 (0.06). The relaxant effect was unaffected by pre-incubation with 100 micro mol/L Nomega-nitro-l-arginine methyl ester (L-NAME). Phentolamine had a potency similar to alfuzosin, with a pIC50 of 7.44 (0.08). Both alfuzosin and phentolamine were completely ineffective on the plateau of contraction induced by 60 mmol/L KCl. In contrast to alfuzosin, sildenafil was equipotent in relaxing the rabbit CC against each contractile agent, with pIC50 values of 7.25 (0.09) and 7.23 (0.22) with 10 micro mol/L phenylephrine and 60 mmol/L KCl, respectively. The relaxant response to sildenafil was partly blocked by pretreatment with 100 micro mol/L L-NAME, with pIC50 values of 7.94 (0.09) and 6.63 (0.32) without and with L-NAME, respectively. Sildenafil, incubated for 45 min at 10 micro mol/L, had no relaxant effect on the resting tension of the preparation or on the concentration-response curve to phenylephrine. CONCLUSIONS The direct relaxant effect of alfuzosin is mediated through alpha1-adrenoceptor blockade. The relaxations induced by phentolamine and alfuzosin are independent of nitric oxide, whereas those induced by sildenafil are, at least partly, sensitive to L-NAME and a selective soluble guanylate cyclase inhibitor, indicating the involvement of nitric oxide and soluble guanylate cyclase. Alfuzosin and phentolamine effectively counteract alpha1-adrenoceptor-mediated contractions of rabbit CC. If valid for human CC, such an effect may contribute to an improved erectile function in patients treated for benign prostatic hyperplasia.
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Affiliation(s)
- S Palea
- Sanofi-Synthélabo Recherche, Department of Internal Medicine, Rueil-Malmaison, France.
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Lin HY, Ballou LM, Lin RZ. Stimulation of the alpha1A adrenergic receptor inhibits PDGF-induced PDGF beta receptor Tyr751 phosphorylation and PI 3-kinase activation. FEBS Lett 2003; 540:106-10. [PMID: 12681492 DOI: 10.1016/s0014-5793(03)00233-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Several reports indicate that some G(alphaq)-coupled receptors antagonize the activation of phosphatidylinositol (PI) 3-kinase by receptor tyrosine kinases. We used Rat-1 fibroblasts expressing the alpha(1A) adrenergic receptor to study how this G(alphaq)-coupled receptor inhibits platelet-derived growth factor (PDGF) activation of PI 3-kinase. Phenylephrine (PE) stimulation of the alpha(1A) adrenergic receptor inhibited PDGF-induced binding of PI 3-kinase to the PDGF receptor (PDGFR) and phosphorylation of the PDGFR at Tyr751, which forms a docking site for PI 3-kinase. By contrast, activation of phospholipase C gamma by PDGF and phosphorylation of the PDGFR at Tyr716 and Tyr771 were not inhibited by PE. The protein tyrosine phosphatase SHP-2, which dephosphorylates Tyr751 on the PDGFR, was more active in cells treated with PDGF plus PE than in cells treated with either agent alone. PDGF-induced PI 3-kinase signaling was also inhibited by treatment of cells with Pasteurella multocida toxin to activate G(alphaq). These results suggest that the alpha(1A) adrenergic receptor, and perhaps other G(alphaq)-coupled receptors, uses tyrosine dephosphorylation to block PI 3-kinase activation by PDGF.
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Affiliation(s)
- Hong-Ying Lin
- Institute of Genetics, Roemerstr 164, University of Bonn, 53117 Bonn, Germany
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Fischer JR, Lane IF, Cribb AE. Urethral pressure profile and hemodynamic effects of phenoxybenzamine and prazosin in non-sedated male beagle dogs. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2003; 67:30-8. [PMID: 12528826 PMCID: PMC227024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Prazosin is a readily available alpha-adrenergic antagonist that may be useful in the management of functional urethral obstruction in companion animals. This study used urethral pressure profilometry to evaluate the urethral effects of prazosin and phenoxybenzamine in healthy, non-sedated, male Beagle dogs. Heart rate, indirect systolic, diastolic and mean arterial blood pressures were measured, and saline perfusion urethral pressure profilometry was performed at 0, 10, 20, and 40 min following intravenous administration of prazosin (0.025 mg/kg), phenoxybenzamine (0.2 mg/kg), or placebo. Maximal urethral pressure, maximal urethral closure pressure, post peak nadir, and all blood pressure parameters decreased significantly at nearly all treatment intervals following administration of prazosin compared with placebo. Less consistently significant reductions were observed following phenoxybenzamine administration. Maximal decreases in urethral pressure parameters were observed 20 min following the injection of prazosin; maximal blood pressure decreases were evident by 10 min postinjection. In this non-sedated dog model, urethral pressure profilometry was a sensitive method of detecting urethral effects of alpha antagonists. Repeatable reductions in urethral pressure measurements were observed, with prazosin effecting more consistently significant changes than phenoxybenzamine. Significant decreases in systolic, diastolic, and mean arterial blood pressures were seen with prazosin, but not phenoxybenzamine or placebo. Further study of selective alpha-1 antagonists in dogs is needed to determine appropriate oral dosing protocols that will produce maximal urethral effects with minimal hemodynamic effects, and to demonstrate clinical efficacy in dogs with functional urethral obstruction.
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Affiliation(s)
- Julie R Fischer
- Department of Companion Animals, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, Prince Edward Island C1A 4P3.
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Eltze M, Grebe T, Michel MC, Czyborra P, Ullrich B. Affinity profile at alpha(1)- and alpha(2)-adrenoceptor subtypes and in vitro cardiovascular actions of (+)-boldine. Eur J Pharmacol 2002; 443:151-68. [PMID: 12044805 DOI: 10.1016/s0014-2999(02)01591-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The present study examines the functional and binding affinities of the aporphine alkaloid, (+)-boldine, at different alpha(1)- and alpha(2)-adrenoceptor subtypes, namely, alpha(1A) (rat vas deferens and kidney) and its L-like state (rabbit spleen), alpha(1B) (guinea pig spleen, mouse spleen and rabbit aorta), alpha(1D) (rat aorta and pulmonary artery), at possible subtypes of prejunctional alpha(2)-adrenoceptors in rat and rabbit vas deferens and rat atrium, alpha(2D) in guinea pig ileum, cloned human alpha(1)-adrenoceptor subtypes A, B and D and alpha(2)-adrenoceptor subtypes A, B and C as well as rat alpha(2D)-adrenoceptors. Additionally, we investigated its Ca(2+) channel antagonism in vascular and cardiac preparations. (+)-Boldine had higher affinity at alpha(1)-adrenoceptor subtype A (pA(2)=7.46, pK(i)=7.21) compared with its L-like state (pA(2)=5.63) or subtype B (pA(2)=5.98- 6.12, pK(i)=5.79) and subtype D (pA(2)=6.18-6.37, pK(i)=6.09). Its affinities at alpha(2)-adrenoceptors in rat and rabbit vas deferens and rat atrium (pA(2)=6.02, 6.36, 6.06, respectively) were identical, but lower at guinea pig ileum alpha(2D)-adrenoceptors (pA(2)=4.38). (+)-Boldine displayed nearly undistinguishable affinity at cloned human alpha(2)-adrenoceptor subtypes A, B and C (pK(i)=6.26, 5.79 and 6.35, respectively), whereas its affinity at rat alpha(2D)-adrenoceptors was low (pK(i)=4.70). In perfused rat kidney, (+)-boldine inhibited K(+)-evoked vasoconstriction at doses 70-fold higher than diltiazem. In guinea pig Langendorff heart, (+)-boldine (10(-5) - 2 x 10(-4) M) was equieffective in increasing coronary flow and in depressing cardiac force, while lower concentrations already depressed heart rate. In papillary muscles from guinea pig, (+)-boldine (10(-6) - 10(-5) M) mainly prolonged the duration of action potential at levels >30% of repolarization. These data reveal that (+)-boldine, except for its moderate selectivity (15 to 25-fold) for alpha(1A)-adrenoceptors, does not discriminate between the alpha(1)-adrenoceptor subtypes B and D and alpha(2)-adrenoceptor subtypes A, B and C, at which the drug consistently displays micromolar affinity. In vascular and cardiac preparations, (+)-boldine, although being at least 50-fold weaker than diltiazem, shows Ca(2+) channel antagonistic properties but no specificity for coronary dilatation relative to cardiodepression.
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Affiliation(s)
- Manfrid Eltze
- Department of Pharmacology, Byk Gulden, D-78467, Konstanz, Germany.
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