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Zagórska A. Phosphodiesterase 10 (PDE10) inhibitors: an updated patent review (2014-present). Expert Opin Ther Pat 2019; 30:147-157. [PMID: 31874060 DOI: 10.1080/13543776.2020.1709444] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Introduction: Phosphodiesterase 10 (PDE10) is one of at least 11 different PDE families, which are the enzymes that degrade adenosine 3',5'-cyclic monophosphate (cAMP) and/or guanosine 3',5'-cyclic monophosphate (cGMP) by hydrolyzing the phosphodiester bonds. Inhibition of PDE10A represents a molecular target in the treatment of conditions that would benefit from the increase of the level of cAMP and/or cGMP such as neurological and psychiatric disorders, cancer, and diabetes.Areas covered: The present article reviews the patent literature on PDE10A inhibitors (PDE10AIs) from 2014 to present and PDE10AI chemotypes from different chemical classes: heteroaryl- and aryl-nitrogen-heterocyclic compounds, unsaturated nitrogen-heterocyclic compounds with specific substituents such as pyrazolopyrimidine, aryloxymethyl cyclopropane, pyridizinone, imidazopyridine, triazoles and imidazo[2,1-a]isoidole. The article presents the potency of PDE10AIs, their efficacy in animal models, and their clinical utility in the treatment of schizophrenia. Therapeutic patents for the treatment of cancers, precancerous conditions, and diabetes were also collected.Expert opinion: Several potent PDE10AIs have been described so far; however, clinical trials have shown that without preclinical optimization, the benefit of PDE10AIs in the treatment of schizophrenia is confounded by a high placebo effect. Understanding of the requirements for PDE10AIs constitutes a challenging but promising field of drug discovery and development.
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Affiliation(s)
- Agnieszka Zagórska
- Department of Medicinal Chemistry, Jagiellonian University Medical College, Kraków, Poland
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Antipsychotic-like effects of a novel phosphodiesterase 10A inhibitor T-251 in rodents. Pharmacol Biochem Behav 2019; 185:172757. [PMID: 31404565 DOI: 10.1016/j.pbb.2019.172757] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/07/2019] [Accepted: 08/09/2019] [Indexed: 01/05/2023]
Abstract
Phosphodiesterase 10A (PDE10A) is a dual-substrate PDE that hydrolyzes both cAMP and cGMP. PDE10A is selectively expressed in medium spiny neurons in the striatum, suggesting the potential of PDE10A inhibitors in the treatment of schizophrenia. This study presents the pharmacological profile of a novel PDE10A inhibitor, 2-[(E)-2-(7-fluoro-3-methylquinoxalin-2-yl)vinyl]-6-pyrrolidin-1-yl-N-(tetrahydro-2H-pyran-4-yl)pyrimidin-4-amine hydrochloride (T-251) in rodent models of schizophrenia. T-251 showed a potent inhibitory activity against human PDE10A (IC50 = 0.050 nmol/L) and showed high selectivity over other PDE families which have over 10,000-fold IC50 values. Oral administration of T-251 (0.1-1.0 mg/kg) increased cAMP and cGMP in the striatum in a dose-dependent manner. Oral administration of T-251 attenuated MK-801 induced hyperactivity (ED50 = 0.68 mg/kg) and suppressed conditioned avoidance response (ID50 = 0.87 mg/kg) in rats in a dose dependent manner. Furthermore, T-251 significantly attenuated MK-801 induced prepulse inhibition deficits and cognitive deficits in rats. Unlike haloperidol and olanzapine, T-251 (1.0-30 mg/kg) did not cause catalepsy in rats. Moreover, T-251 (0.6 and 6.0 mg/kg) did not increase plasma levels of prolactin at 1 h after administration, whereas haloperidol and olanzapine significantly increased them. The antipsychotic-like effects and cognitive enhancement of T-251 without catalepsy or plasma prolactin elevation observed in rats suggests that T-251 would be a novel antipsychotic with an improved side-effect profile.
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Discovery of a pyrazolo[1,5-a]pyrimidine derivative (MT-3014) as a highly selective PDE10A inhibitor via core structure transformation from the stilbene moiety. Bioorg Med Chem 2019; 27:3440-3450. [DOI: 10.1016/j.bmc.2019.06.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 11/18/2022]
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Design and synthesis of novel 5-(3,4,5-trimethoxybenzoyl)-4-aminopyrimidine derivatives as potent and selective phosphodiesterase 5 inhibitors: Scaffold hopping using a pseudo-ring by intramolecular hydrogen bond formation. Bioorg Med Chem Lett 2014; 24:5175-80. [DOI: 10.1016/j.bmcl.2014.09.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 09/23/2014] [Accepted: 09/27/2014] [Indexed: 11/20/2022]
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Plisson C, Weinzimmer D, Jakobsen S, Natesan S, Salinas C, Lin SF, Labaree D, Zheng MQ, Nabulsi N, Marques TR, Kapur S, Kawanishi E, Saijo T, Gunn RN, Carson RE, Rabiner EA. Phosphodiesterase 10A PET Radioligand Development Program: From Pig to Human. J Nucl Med 2014; 55:595-601. [DOI: 10.2967/jnumed.113.131409] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Polcari AJ, Farooq AV, Woods ME, Ripsch MS, Picken M, Turk TMT, White FA. Effect of the phosphodiesterase-5 inhibitor zaprinast on ischemia-reperfusion injury in rats. J Endourol 2013; 27:338-42. [PMID: 22974473 DOI: 10.1089/end.2012.0198] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The cardiac and renal protective effects of phosphodiesterase-5 (PDE-5) inhibitors against ischemia-reperfusion injury have recently been demonstrated in animal studies. We evaluated the effect of pretreatment with the PDE-5 inhibitor zaprinast on warm renal ischemia in a rat model. METHODS Female Sprague-Dawley rats underwent concomitant right nephrectomy and left renal hilar occlusion for 30 minutes. Twelve animals were equally divided into three groups: Group 1 received no pharmacologic pretreatment, group 2 was pretreated with zaprinast 10 mg/kg, and group 3 was pretreated with zaprinast 20 mg/kg. Zaprinast was dissolved in 25% dimethyl sulfoxide and given as a single intraperitoneal injection 30 minutes before surgery. Serum blood urea nitrogen (BUN) and creatinine levels, histopathology, and TUNEL staining for apoptosis were assessed 24 hours postoperatively. RESULTS The mean creatinine level for groups 1, 2, and 3 was 0.73 mg/dL, 0.55 mg/dL, and 0.38 mg/dL, respectively. These values were not statistically different (P=0.099). The mean BUN levels of 35.8 mg/dL for group 1, 27.3 mg/dL for group 2, and 23.3 mg/dL for group 3 were also statistically similar (P=0.278). There were no objective differences in histopathologic evaluation or TUNEL staining between the groups. CONCLUSION This study did not demonstrate a beneficial effect of zaprinast pretreatment on renal parameters after warm ischemic injury.
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Affiliation(s)
- Anthony J Polcari
- Department of Urology and Pathology, 4 Loyola University Medical Center, Maywood, IL 60153, USA.
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Kotera J, Mochida H, Inoue H, Noto T, Fujishige K, Sasaki T, Kobayashi T, Kojima K, Yee S, Yamada Y, Kikkawa K, Omori K. Avanafil, a Potent and Highly Selective Phosphodiesterase-5 Inhibitor for Erectile Dysfunction. J Urol 2012; 188:668-74. [DOI: 10.1016/j.juro.2012.03.115] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Indexed: 01/02/2023]
Affiliation(s)
- Jun Kotera
- Advanced Medical Research Laboratories, Mitsubishi Tanabe Pharma Corp., Yokohama, Japan
| | - Hideki Mochida
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | - Hirotaka Inoue
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | - Tsunehisa Noto
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | - Kotomi Fujishige
- Advanced Medical Research Laboratories, Mitsubishi Tanabe Pharma Corp., Yokohama, Japan
| | - Takashi Sasaki
- Advanced Medical Research Laboratories, Mitsubishi Tanabe Pharma Corp., Yokohama, Japan
| | - Tamaki Kobayashi
- Advanced Medical Research Laboratories, Mitsubishi Tanabe Pharma Corp., Yokohama, Japan
| | - Koki Kojima
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | | | - Yasuhiro Yamada
- DMPK Research Laboratories, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | - Kohei Kikkawa
- DMPK Research Laboratories, Mitsubishi Tanabe Pharma Corp., Saitama, Japan
| | - Kenji Omori
- Advanced Medical Research Laboratories, Mitsubishi Tanabe Pharma Corp., Yokohama, Japan
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Sudachitin, a polymethoxyflavone from Citrus sudachi, suppresses lipopolysaccharide-induced inflammatory responses in mouse macrophage-like RAW264 cells. Biosci Biotechnol Biochem 2012; 76:598-600. [PMID: 22451408 DOI: 10.1271/bbb.110800] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Although some polymethoxyflavones possess several important biological properties, including neuroprotective, anticancer, and anti-inflammatory ones, sudachitin, a polymethoxyflavone from Citrus sudachi, has been little studied. In this study, we found that sudachitin inhibited nitric oxide production by suppressing the expression of inducible nitric oxide synthase in lipopolysaccharide-stimulated macrophages, indicating that sudachitin has an anti-inflammatory effect.
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Pontes LB, Antunes F, Sudo RT, Raimundo JM, Lima LM, Barreiro EJ, Zapata-Sudo G. Vasodilatory activity and antihypertensive profile mediated by inhibition of phosphodiesterase type 1 induced by a novel sulfonamide compound. Fundam Clin Pharmacol 2011; 26:690-700. [PMID: 22066694 DOI: 10.1111/j.1472-8206.2011.00999.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
LASSBio-985 is a sulfonamide compound designed as a simplified structure of a nonselective phosphodiesterase type 4 (PDE-4) inhibitor that promotes vasodilatory activity in vitro. PDE are enzymes responsible for the hydrolysis of cyclic adenosine 3',5'- monophosphate and cyclic guanosine 3',5'-monophosphate. Five different isozymes of PDE are found in vascular smooth muscle (PDE1-PDE5). Aortic rings, with or without endothelium, from male normotensive and spontaneously hypertensive rats (SHR) were prepared for isometric tension recording. Blood pressure was measured in Wistar Kyoto (WKY) rats and SHR during intravenous infusion of LASSBio-985 (10 mg/kg/min) during 15 min. LASSBio-985 induced a concentration-dependent vasodilation in aortic rings from normotensive and SHR, which was almost completely inhibited in endothelium-denuded vessels. Vasodilatory activity was also reduced in endothelium-intact aortic rings that had been pretreated with N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME), a nitric oxide synthase inhibitor and 1H-[1,2,4]oxadiazolod[4,3-a]quinoxalin-1-one (ODQ), a guanylate cyclase inhibitor. LASSBio-985-induced vasodilation was also inhibited by sildenafil (100 μm) and SQ 22536, a PDE5 inhibitor and adenylate cyclase inhibitor, respectively. To evaluate the involvement of some endothelial receptors, atropine, diphenhydramine, HOE 140, naloxone, propranolol, indomethacin, and wortmannin were tested, but none inhibited the effects of LASSBio-985. The residual effect observed on endothelium-denuded aortic rings was abolished by nicardipine, a voltage-sensitive-Ca(2+)-channel blocker. Intravenous infusion of LASSBio-985 (10 mg/kg/min) significantly reduced systolic and diastolic pressures in both WKY and SHR. LASSBio-985 is a compound with vasodilatory activity, which could be consequent to PDE1 inhibition and voltage-sensitive-Ca(2+)-channel blockade.
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Affiliation(s)
- Luana Braga Pontes
- Programa de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Centro de Ciências da Saúde, Bloco J, Sala 14, 21941-590, Rio de Janeiro, Brazil
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Eardley I, Donatucci C, Corbin J, El-Meliegy A, Hatzimouratidis K, McVary K, Munarriz R, Lee SW. Pharmacotherapy for Erectile Dysfunction. J Sex Med 2010; 7:524-40. [DOI: 10.1111/j.1743-6109.2009.01627.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Theo Schermuly R, Ardeschir Ghofrani H, Weissmann N. Prostanoids and phosphodiesterase inhibitors in experimental pulmonary hypertension. Curr Top Dev Biol 2009; 67:251-84. [PMID: 15949537 DOI: 10.1016/s0070-2153(05)67008-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Pulmonary arterial hypertension (PAH) is a progressive disease with a poor prognosis, characterized by intimal lesions, medial hypertrophy, and adventitial thickening of precapillary pulmonary arteries. Several approved therapies are currently available for the treatment of PAH, of which intravenous epoprostenol is the best explored over the past decade. Newly available oral endothelin receptor antagonists, although clinically efficacious, bear the risk of liver toxicity in a significant portion of patients. Substances that stimulate the formation of the second messengers cyclic adenosine monophosphate (cAMP) or guanosine monophosphate (cGMP) have proved useful in the treatment of various forms of pre-capillary pulmonary hypertension. These second messengers of the endogenous vasodilator mediators that include prostacyclin and nitric oxide (NO) are hydrolyzed by cyclic nucleotide phosphodiesterases (PDEs), a class of enzymes from which 11 isoforms have been characterized. This chapter highlights developments in the treatment of experimental pulmonary hypertension with special attention to prostanoids and PDE inhibitors. We summarize findings for the acute vasodilatory as well as chronic effects of prostanoids, PDE inhibitors, or combinations of both, in animal models of pulmonary hypertension.
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Affiliation(s)
- Ralph Theo Schermuly
- Department of Internal Medicine II, Justus-Liebig University Giessen, 35392 Giessen, Germany
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Identification of compounds that potentiate CREB signaling as possible enhancers of long-term memory. Proc Natl Acad Sci U S A 2009; 106:2412-7. [PMID: 19196967 DOI: 10.1073/pnas.0813020106] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Many studies have implicated the cAMP Response Element Binding (CREB) protein signaling pathway in long-term memory. To identify small molecule enhancers of CREB activation of gene expression, we screened approximately 73,000 compounds, each at 7-15 concentrations in a quantitative high-throughput screening (qHTS) format, for activity in cells by assaying CREB mediated beta-lactamase reporter gene expression. We identified 1,800 compounds that potentiated CREB mediated gene expression, with potencies as low as 16 nM, comprising 96 structural series. Mechanisms of action were systematically determined, and compounds that affect phosphodiesterase 4, protein kinase A, and cAMP production were identified, as well as compounds that affect CREB signaling via apparently unidentified mechanisms. qHTS followed by interrogation of pathway targets is an efficient paradigm for lead generation for chemical genomics and drug development.
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Sandner P, Svenstrup N, Tinel H, Haning H, Bischoff E. Phosphodiesterase 5 inhibitors and erectile dysfunction. Expert Opin Ther Pat 2008. [DOI: 10.1517/13543776.18.1.21] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Martins MAP, Emmerich D, Beck P, Cunico W, Pereira CMP, Sinhorin AP, Brondani S, Peres R, Teixeira MVM, Bonacorso HG, Zanatta N. One‐Pot Synthesis of Pyrazole‐5(3)‐carboxyamides. SYNTHETIC COMMUN 2006. [DOI: 10.1081/scc-120034176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Marcos A. P. Martins
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Daniel Emmerich
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Paulo Beck
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Wilson Cunico
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Claudio M. P. Pereira
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Adilson P. Sinhorin
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Sergio Brondani
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Rodrigo Peres
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Marcos V. M. Teixeira
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Helio G. Bonacorso
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
| | - Nilo Zanatta
- a Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química , Universidade Federal de Santa Maria , 97.105‐900, Santa Maria, RS, Brazil
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Taniguchi Y, Tonai-Kachi H, Shinjo K. Zaprinast, a well-known cyclic guanosine monophosphate-specific phosphodiesterase inhibitor, is an agonist for GPR35. FEBS Lett 2006; 580:5003-8. [PMID: 16934253 DOI: 10.1016/j.febslet.2006.08.015] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Revised: 08/09/2006] [Accepted: 08/09/2006] [Indexed: 11/21/2022]
Abstract
We found that zaprinast, a well-known cyclic guanosine monophosphate-specific phosphodiesterase inhibitor, acted as an agonist for a G protein-coupled receptor, GPR35. In our intracellular calcium mobilization assay, zaprinast activated rat GPR35 strongly (geometric mean EC(50) value of 16nM), whereas it activated human GPR35 moderately (geometric mean EC(50) value of 840nM). We also demonstrated that GPR35 acted as a Galpha(i/o)- and Galpha(16)-coupled receptor for zaprinast when heterologously expressed in human embryonic kidney 293 (HEK 293) cells. These findings will facilitate the research on GPR35 and the drug discovery of the GPR35 modulators.
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Affiliation(s)
- Yasuhito Taniguchi
- Discovery Biology Research, Pfizer Global Research and Development, Nagoya Laboratories, Pfizer Inc., 5-2 Taketoyo, Aichi 470-2393, Japan
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de Vente J, Markerink-van Ittersum M, Vles JSH. The role of phosphodiesterase isoforms 2, 5, and 9 in the regulation of NO-dependent and NO-independent cGMP production in the rat cervical spinal cord. J Chem Neuroanat 2006; 31:275-303. [PMID: 16621445 DOI: 10.1016/j.jchemneu.2006.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2005] [Revised: 02/17/2006] [Accepted: 02/20/2006] [Indexed: 10/24/2022]
Abstract
NO-responsive, cGMP-producing structures are abundantly present in the cervical spinal cord. NO-mediated cGMP synthesis has been implicated in nociceptive signaling and it has been demonstrated that cGMP has a role establishing synaptic connections in the spinal cord during development. As cGMP levels are controlled by the activity of soluble guanylyl cyclase (synthesis) and the phosphodiesterase (PDE) activity (breakdown), we studied the influence of PDE activity on NO-stimulated cGMP levels in the rat cervical spinal cord. cGMP-immunoreactivity (cGMP-IR) was localized in sections prepared from slices incubated in vitro. A number of reported PDE isoform-selective PDE inhibitors was studied in combination with diethylamineNONOate (DEANO) as a NO-donor including isobutyl-methylxanthine (IBMX) as a non-selective PDE inhibitor. We studied 8-methoxy-IBMX as a selective PDE1 inhibitor, erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) and BAY 60-7550 as selective PDE2 inhibitors, sildenafil as a selective PDE5 inhibitor, dipyridamole as a mixed type PDE5 and PDE10 inhibitor, rolipram as a PDE4 inhibitor, and SCH 81566 as a selective PDE9 inhibitor. cGMP-IR structures (nerve fibers, axons, and terminals) were characterized using the following neurochemical markers: vesicular transporter molecules for acetylcholine, GABA, and glutamate (type 1 and type 2), parvalbumin, glutamate transporter molecule EAAT3, synaptophysin, substance P, calcitonin gene-related peptide, and isolectin B4. Most intense cGMP-IR was observed in the dorsal lamina. Ventral motor neurons were devoid of cGMP-IR. cGMP-IR was observed in GABAergic, and glutamatergic terminals in all gray matter laminae. cGMP-IR was abundantly colocalized with anti-vesicular glutamate transporter 2 (vGLUT2), however not with the anti-vesicular glutamate transporter 1 (vGLUT1), suggesting a functional difference between structures expressing vGLUT1 or vGLUT2. cGMP-IR did not colocalize with substance P- or calcitonin-gene related peptide-IR structures, however did partially colocalize with isolectin B4 in the dorsal horn. cGMP-IR in cholinergic structures was observed in dorsal root fibers entering the spinal cord, occasionally in laminae 1-3, in laminae 8 and 9 in isolated boutons and in the C-type terminals, and in small cells and varicosities in lamina 10. This latter observation suggests that the proprioceptive interneurons arising in lamina 10 are also NO-responsive. No region-specific nor a constant co-expression of cGMP-IR with various neuronal markers was observed after incubation of the slices with one of the selected PDE inhibitors. Expression of the mRNA of PDE2, 5, and 9 was observed in all lamina. The ventral motor neurons and the ependymal cells lining the central canal expressed all three PDE isoforms. Incubation of the slices in the presence of IBMX, DEANO in combination with BAY 41-2272, a NO-independent activator of soluble guanylyl cyclase, provided evidence for endogenous NO synthesis in the slice preparations and enhanced cGMP-IR in all lamina. Under these conditions cGMP-IR colocalized with substance P in a subpopulation of substance P-IR fibers. It is concluded that NO functions as a retrograde neurotransmitter in the spinal cord but that also postsynaptic structures are NO-responsive by producing cGMP. cGMP-IR in a subpopulation of isolectin B4 positive fibers and boutons is indicative for a role of NO-cGMP signaling in nociceptive processing. cGMP levels in the spinal cord are controlled by the concerted action of a number of PDE isoforms, which can be present in the same cell.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/drug effects
- 3',5'-Cyclic-AMP Phosphodiesterases/genetics
- 3',5'-Cyclic-AMP Phosphodiesterases/metabolism
- 3',5'-Cyclic-GMP Phosphodiesterases/drug effects
- 3',5'-Cyclic-GMP Phosphodiesterases/genetics
- 3',5'-Cyclic-GMP Phosphodiesterases/metabolism
- Animals
- Biomarkers/metabolism
- Cervical Vertebrae
- Cyclic GMP/biosynthesis
- Cyclic Nucleotide Phosphodiesterases, Type 1
- Cyclic Nucleotide Phosphodiesterases, Type 2
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Enzyme Inhibitors/pharmacology
- Immunohistochemistry
- Male
- Nerve Tissue Proteins/metabolism
- Neurons/cytology
- Neurons/drug effects
- Neurons/metabolism
- Neurotransmitter Agents/metabolism
- Nitric Oxide/metabolism
- Nitric Oxide Donors/pharmacology
- Pain/metabolism
- Pain/physiopathology
- Phosphoric Diester Hydrolases/drug effects
- Phosphoric Diester Hydrolases/genetics
- Phosphoric Diester Hydrolases/metabolism
- Plant Lectins
- Presynaptic Terminals/drug effects
- Presynaptic Terminals/metabolism
- Protein Isoforms/drug effects
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- Rats
- Rats, Inbred Lew
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Spinal Cord/cytology
- Spinal Cord/metabolism
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Affiliation(s)
- J de Vente
- European Graduate School of Neuroscience (EURON), Maastricht University, Department of Psychiatry and Neuropsychology, UNS50, POB 616, 6200 MD Maastricht, The Netherlands.
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Yamamoto T, Wada A, Tsutamoto T, Ohnishi M, Horie M. Long-term treatment with a phosphodiesterase type 5 inhibitor improves pulmonary hypertension secondary to heart failure through enhancing the natriuretic peptides-cGMP pathway. J Cardiovasc Pharmacol 2005; 44:596-600. [PMID: 15505498 DOI: 10.1097/00005344-200411000-00013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In advanced heart failure (HF), the compensatory pulmonary vasodilation is attenuated due to the relative insufficiency of cGMP despite increased secretion of natriuretic peptides (NPs). Phosphodiesterase type 5 (PDE5) inhibitors prevent cGMP degradation, and thus may potentiate the effect of the NPs-cGMP pathway. We orally administered a specific PDE5 inhibitor, T-1032 (1 mg/kg; twice a day, n = 7) or placebo (n = 7) for 2 weeks in dogs with HF induced by rapid pacing (270 bpm, 3 weeks) and examined the plasma levels of atrial natriuretic peptide (ANP), cGMP, and hemodynamic parameters. We also examined the hemodynamic changes after injection of a specific NPs receptor antagonist, HS-142-1 (3 mg/kg), under treatment with T-1032. T-1032 significantly increased plasma cGMP levels compared with the vehicle group despite low plasma ANP levels associated with improvement in cardiopulmonary hemodynamics. HS-142-1 significantly decreased plasma cGMP levels in both groups, whereas it did not change all hemodynamic parameters in the vehicle group. In contrast, in the T-1032 group, HS-142-1 significantly increased pulmonary arterial pressure and pulmonary vascular resistance. These results indicated that long-term treatment with a PDE5 inhibitor improved pulmonary hypertension secondary to HF and the NPs-cGMP pathway contributed to this therapeutic effect.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases
- Administration, Oral
- Animals
- Atrial Natriuretic Factor/blood
- Blood Pressure/drug effects
- Cardiac Output/drug effects
- Cardiac Pacing, Artificial/methods
- Cyclic GMP/antagonists & inhibitors
- Cyclic GMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Disease Models, Animal
- Dogs
- Drug Administration Schedule
- Drug Evaluation, Preclinical/methods
- Heart Failure/complications
- Heart Failure/drug therapy
- Heart Rate/drug effects
- Heart Ventricles/drug effects
- Heart Ventricles/physiopathology
- Hypertension, Pulmonary/complications
- Hypertension, Pulmonary/drug therapy
- Hypertension, Pulmonary/prevention & control
- Injections, Intravenous
- Isoquinolines/blood
- Isoquinolines/pharmacology
- Japan
- Lung/blood supply
- Lung/drug effects
- Myocardial Contraction/drug effects
- Natriuretic Peptides/metabolism
- Natriuretic Peptides/therapeutic use
- Norepinephrine/blood
- Phosphodiesterase Inhibitors/pharmacology
- Phosphodiesterase Inhibitors/therapeutic use
- Phosphoric Diester Hydrolases/metabolism
- Polysaccharides/adverse effects
- Polysaccharides/blood
- Polysaccharides/therapeutic use
- Pyridines/blood
- Pyridines/pharmacology
- Receptors, Atrial Natriuretic Factor/administration & dosage
- Receptors, Atrial Natriuretic Factor/antagonists & inhibitors
- Receptors, Atrial Natriuretic Factor/therapeutic use
- Time Factors
- Vascular Resistance/drug effects
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Affiliation(s)
- Takashi Yamamoto
- Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
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18
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Mochida H, Noto T, Inoue H, Yano K, Kikkawa K. T-0156, a novel phosphodiesterase type 5 inhibitor, and sildenafil have different pharmacological effects on penile tumescence and electroretinogram in dogs. Eur J Pharmacol 2004; 485:283-8. [PMID: 14757152 DOI: 10.1016/j.ejphar.2003.11.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
T-0156 (2-(2-methylpyridin-4-yl)methyl-4-(3,4,5-trimethoxyphenyl)-8-(pyrimidin-2-yl)methoxy-1,2-dihydro-1-oxo-2,7-naphthyridine-3-carboxylic acid methyl ester hydrochloride) is a newly synthesized phosphodiesterase type 5 inhibitor, and its potency and selectivity are higher than those of sildenafil in an enzyme assay. In the present study with anesthetized dogs, we examined the effects of intravenous T-0156 or sildenafil on the pelvic nerve stimulation-induced penile tumescence and light-adapted flicker stimulation-induced electroretinogram, parameters of which are reported to be indicators for inhibition of phosphodiesterase type 5 and type 6, respectively. Both compounds potentiated the penile tumescence in a dose-dependent manner. T-0156 at 10 microg/kg and sildenafil at 100 microg/kg showed almost the same potentiating percentage (181.5+/-31.1% and 190.0+/-37.9%) in spite of the plasma concentration of T-0156 being about five times lower than that of sildenafil (16.7+/-1.6 and 78.8+/-5.3 ng/ml), indicating that the effect of T-0156 on tumescence is more potent than that of sildenafil. While the high dose of T-0156 (1000 microg/kg) reduced the amplitude and increased the latency of the electroretinogram positive wave, the effects of T-0156 were conversely weaker than those of sildenafil (reduction of amplitude; T-0156: 41.1+/-8.0%, sildenafil: 71.7+/-3.9%, increase of latency; T-0156: 3.9+/-0.6%, sildenafil: 14.5+/-1.4%, at 1000 microg/kg). These results clearly showed the difference in the properties of T-0156 and sildenafil in pharmacological studies with anesthetized dogs, and the difference appeared to correspond with their inhibitory potencies for phosphodiesterase type 5 and type 6. It was concluded that T-0156 would be a useful pharmacological tool as a potent and highly selective phosphodiesterase type 5 inhibitor.
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Affiliation(s)
- Hideki Mochida
- Discovery and Pharmacology Research Laboratories, Tanabe Seiyaku Co., Ltd., 2-2-50, Kawagishi, Toda, Saitama 335-8505, Japan.
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19
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Mahajan H, Richards SM, Rattigan S, Clark MG. T-1032, a cyclic GMP phosphodiesterase-5 inhibitor, acutely blocks physiologic insulin-mediated muscle haemodynamic effects and glucose uptake in vivo. Br J Pharmacol 2003; 140:1283-91. [PMID: 14581178 PMCID: PMC1574135 DOI: 10.1038/sj.bjp.0705548] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
1. Cyclic GMP phosphodiesterase-5 inhibitors have been shown to alter blood flow in specific tissues by potentiating local NO-dependent vasodilatory mechanisms. Since the haemodynamic effects of physiologic insulin, particularly capillary recruitment, may be critical for muscle glucose uptake in vivo and are blocked by inhibitors of nitric oxide synthase, we have explored the acute effects of the specific cGMP phosphodiesterase-5 inhibitor T-1032 on physiologic insulin action in anaesthetized healthy rats in vivo. 2. Whole-body glucose infusion (GIR), femoral blood flow (FBF), hind leg vascular resistance (VR), hind leg glucose uptake (HGU), 2-deoxyglucose uptake into muscles of the lower leg (R'g), hind leg metabolism of infused 1-methylxanthine (1-MX), a measure of capillary recruitment, and muscle cGMP were determined. The experimental groups were T-1032 (10 microg min-1 kg-1) infused for 1 h before and during a euglycaemic insulin clamp (3 mU min-1 kg-1 x 2 h), T-1032 infused for 3 h with saline, T-1032 during a 2 h clamp, T-1032 with saline for 2 h, and a 2 h saline control. 3. Insulin increased GIR from zero to 13 mg min-1 kg-1, HGU from 0.1+/-0.01 to 0.43+/-0.05 micromol min-1, R'g and 1-MX, marginally increased FBF, and had no effect on blood pressure or heart rate. T-1032 alone had no effect on blood pressure, heart rate, FBF, VR, HGU, R'g or 1-MX, but increased muscle cGMP. T-1032 1 h before and during insulin completely blocked GIR (1 h), HGU (2 h), R'g (2 h), and 1-MX (2 h). T-1032 commenced with insulin had only partial blocking activity against insulin. 4. We conclude that T-1032 is a potent acutely acting inhibitor of the muscle effects of physiologic insulin on capillary recruitment and glucose uptake in vivo. These, together with inhibition of whole-body glucose infusion during insulin, may caution against the use of isoenzyme-5-specific cyclic GMP phosphodiesterase inhibitors as therapeutic agents.
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Affiliation(s)
- Hema Mahajan
- Biochemistry, Medical School, University of Tasmania, Private Bag 58, Hobart, Tasmania 7001, Australia
| | - Stephen M Richards
- Biochemistry, Medical School, University of Tasmania, Private Bag 58, Hobart, Tasmania 7001, Australia
| | - Stephen Rattigan
- Biochemistry, Medical School, University of Tasmania, Private Bag 58, Hobart, Tasmania 7001, Australia
| | - Michael G Clark
- Biochemistry, Medical School, University of Tasmania, Private Bag 58, Hobart, Tasmania 7001, Australia
- Author for correspondence:
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20
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Cobb BR, Fan L, Kovacs TE, Sorscher EJ, Clancy JP. Adenosine receptors and phosphodiesterase inhibitors stimulate Cl- secretion in Calu-3 cells. Am J Respir Cell Mol Biol 2003; 29:410-8. [PMID: 12714375 DOI: 10.1165/rcmb.2002-0247oc] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We investigated cystic fibrosis transmembrane conductance regulator (CFTR) activation by clinically used phosphodiesterase inhibitors (PDEis) in Calu-3 cell monolayers alone and in combination with A2B adenosine receptor stimulation. This receptor pathway has previously been shown to activate wild-type and mutant CFTR molecules. Several PDEis, including milrinone, cilostazol (Pletal), papaverine, rolipram, and sildenafil (Viagra), produced a short circuit current (Isc) that was glibenclamide-sensitive, achieving 20-85% of forskolin-stimulated Isc. Papaverine, cilostazol, and rolipram also augmented both the magnitude and the duration of Isc following low dose stimulation of adenosine receptors with Ado (0.1-1.0 microM, P < 0.01). Subsequent studies demonstrated that very low concentrations of cilostazol or papaverine (approximately 1/2 peak serum concentrations) were sufficient to activate Isc, and both agents markedly augmented Ado-stimulated Isc (1 microM, P < 0.01). Our results provide evidence that select PDEis, at concentrations achieved as part of systemic therapies, can activate CFTR-dependent Isc in Calu-3 cell monolayers. These studies also indicate that PDEis have the capacity to augment an endogenous CFTR-activating pathway in an "in vivo"-like model system, and supports future investigations of these agents relevant to cystic fibrosis.
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Affiliation(s)
- Bryan R Cobb
- Department of Human Genetics, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 35233, USA
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21
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Qiu Y, Bhattacharjee S, Kraft P, John TM, Craig E, Haynes-Johnson D, Guan J, Jiang W, Macielag M, Sui Z, Clancy J, Lundeen S. Characterization of a novel phosphodiesterase type 5 inhibitor: JNJ-10258859. Eur J Pharmacol 2003; 472:73-80. [PMID: 12860475 DOI: 10.1016/s0014-2999(03)01868-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have characterized a novel, potent, and selective phosphodiesterase type 5 inhibitor, JNJ-10258859 ((R)-(-)-3-(2,3-dihydro-benzofuran-5-yl)-2-[5-(4-methoxy-phenyl)-pyrimidin-2-yl]-1,2,3,4-tetrahydro-pyrrolo[3,4-b]quinolin-9-one). Its inhibitory effects on phosphodiesterase 1-6 were determined using enzymes partially purified from human tissues. The compound inhibited phosphodiesterase type 5 with a K(i) of 0.23 nM and displayed excellent selectivity versus phosphodiesterase types 1-4 (>/=22,000 fold compared to phosphodiesterase type 5). It had 27-fold selectivity over phosphodiesterase type 6 as well. In a cell-based assay, JNJ-10258859 was more potent than sildenafil in potentiating nitric oxide (NO) induced accumulation of intracellular cGMP. The in vivo effect of JNJ-10258859 was evaluated in an anesthetized dog model via intravenous administration. The compound had similar efficacy to sildenafil in enhancing both the amplitude and duration of intracavernosal pressure increase induced by electrical stimulation to the pelvic nerve. No significant effects on either mean aortic pressure or heart rate were observed during the course of the experiments. This data suggests that JNJ-10258859 could be a useful treatment for erectile dysfunction.
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Affiliation(s)
- Yuhong Qiu
- Reproductive Therapeutics, Drug Discovery, R.W. Johnson and Johnson Pharmaceutical Research and Development Institute, LLC. 1000 Route 202, Raritan, NJ 08869, USA.
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22
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Haning H, Niewöhner U, Bischoff E. Phosphodiesterase type 5 (PDE5) inhibitors. PROGRESS IN MEDICINAL CHEMISTRY 2003; 41:249-306. [PMID: 12774696 DOI: 10.1016/s0079-6468(02)41007-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Helmut Haning
- BAYER AG Pharmaceutical Business Group, Medicinal Chemistry, D-42096 Wuppertal, Germany
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23
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Toda N, Okamura T. The pharmacology of nitric oxide in the peripheral nervous system of blood vessels. Pharmacol Rev 2003; 55:271-324. [PMID: 12773630 DOI: 10.1124/pr.55.2.3] [Citation(s) in RCA: 221] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Unanticipated, novel hypothesis on nitric oxide (NO) radical, an inorganic, labile, gaseous molecule, as a neurotransmitter first appeared in late 1989 and into the early 1990s, and solid evidences supporting this idea have been accumulated during the last decade of the 20th century. The discovery of nitrergic innervation of vascular smooth muscle has led to a new understanding of the neurogenic control of vascular function. Physiological roles of the nitrergic nerve in vascular smooth muscle include the dominant vasodilator control of cerebral and ocular arteries, the reciprocal regulation with the adrenergic vasoconstrictor nerve in other arteries and veins, and in the initiation and maintenance of penile erection in association with smooth muscle relaxation of the corpus cavernosum. The discovery of autonomic efferent nerves in which NO plays key roles as a neurotransmitter in blood vessels, the physiological roles of this nerve in the control of smooth muscle tone of the artery, vein, and corpus cavernosum, and pharmacological and pathological implications of neurogenic NO have been reviewed. This nerve is a postganglionic parasympathetic nerve. Mechanical responses to stimulation of the nerve, mainly mediated by NO, clearly differ from those to cholinergic nerve stimulation. The naming "nitrergic or nitroxidergic" is therefore proposed to avoid confusion of the term "cholinergic nerve", from which acetylcholine is released as a major neurotransmitter. By establishing functional roles of nitrergic, cholinergic, adrenergic, and other autonomic efferent nerves in the regulation of vascular tone and the interactions of these nerves in vivo, especially in humans, progress in the understanding of cardiovascular dysfunctions and the development of pharmacotherapeutic strategies would be expected in the future.
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Affiliation(s)
- Noboru Toda
- Toyama Institute for Cardiovascular Pharmacology Research, Toyama Bldg., 7-13, 1-Chome, Azuchi-machi, Chuo-ku, Osaka 541-0052, Japan.
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24
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Gamanuma M, Yuasa K, Sasaki T, Sakurai N, Kotera J, Omori K. Comparison of enzymatic characterization and gene organization of cyclic nucleotide phosphodiesterase 8 family in humans. Cell Signal 2003; 15:565-74. [PMID: 12681444 DOI: 10.1016/s0898-6568(02)00146-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Full-length cDNAs of human cyclic nucleotide phosphodiesterase 8B (PDE8B) were isolated. Enzymatic characteristics of a dominant variant encoding a protein of 885 residues (PDE8B1) were compared with those of PDE8A1. The recombinant PDE8A1 and PDE8B1 proteins of an entire form were produced in both cytosolic and membrane fractions of the transfected COS cells. The human PDE8B1 was a high-affinity cAMP-PDE with K(m) value of 101+/-12 nM for cAMP, which is greater than that of PDE8A1 (40+/-1 nM). Relative V(max) value of PDE8A1 was 57+/-8% compared with that of PDE8B1 (100+/-12%). Although PDE8A1 was moderately inhibited by dipyridamole with IC(50) value of 8+/-2 microM, the compound antagonized the PDE8B1 activity at three-fold higher concentration (IC(50)=23+/-2 microM). The human PDE8B gene was composed of 22 exons, spanning over 217 kb. Although overall sequence identity between PDE8A1 and PDE8B1 was 68%, positions of junctions of each exon between the PDE8A1 and PDE8B1 sequences were well matched, indicating evolutionary relatedness of both genes.
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Affiliation(s)
- Michiko Gamanuma
- Discovery Research Laboratory, Tanabe Seiyaku Co. Ltd, 2-50, Kawagishi-2-chome, Toda, Saitama 335-8505, Japan
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25
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Nakamizo T, Kawamata J, Yoshida K, Kawai Y, Kanki R, Sawada H, Kihara T, Yamashita H, Shibasaki H, Akaike A, Shimohama S. Phosphodiesterase inhibitors are neuroprotective to cultured spinal motor neurons. J Neurosci Res 2003; 71:485-95. [PMID: 12548704 DOI: 10.1002/jnr.10483] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We have previously reported that cyclic guanosine-3',5'-monophosphate (cGMP) protects spinal motor neurons against acute reactive oxygen species (ROS)-induced toxicity but not against chronic ROS-induced or glutamate (Glu)-induced toxicity. In this study, we investigated the effects of phosphodiesterase (PDE) inhibitors on the survival of cultured spinal motor neurons. Selective PDE5 inhibitors (dipyridamole, T-1032, and zaprinast) as well as a nonselective PDE inhibitor (aminophylline) protected motor and nonmotor neurons against both acute ROS-induced and chronic Glu-induced neurotoxicity, whereas selective inhibitors of PDE1-4 offered no protection. 8-Bromo-cGMP (8br-cGMP), a cGMP analogue, protected both motor and nonmotor neurons against acute ROS-induced toxicity but protected only nonmotor neurons against chronic Glu-induced toxicity. This neuroprotection was blocked by KT5823, a cGMP-dependent protein kinase (PKG) inhibitor. Immunohistochemical staining confirmed that PDE5 and PKG are located in almost all rat lumbar spinal neurons. Furthermore, semiquantitative analysis of the immunostaining intensity revealed that PDE5 was more abundant in motor neurons than in nonmotor neurons. Our results suggest that this difference in the amount of PDE5 may be responsible for the vulnerability of motor neurons to chronic excitotoxicity. In addition, the results of this study raise the possibility that PDE5 inhibitors might be used as a treatment for amyotrophic lateral sclerosis.
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Affiliation(s)
- Tomoki Nakamizo
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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26
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Mochida H, Takagi M, Inoue H, Noto T, Yano K, Fujishige K, Sasaki T, Yuasa K, Kotera J, Omori K, Kikkawa K. Enzymological and pharmacological profile of T-0156, a potent and selective phosphodiesterase type 5 inhibitor. Eur J Pharmacol 2002; 456:91-8. [PMID: 12450574 DOI: 10.1016/s0014-2999(02)02590-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The enzymological and pharmacological properties of 2-(2-Methylpyridin-4-yl)methyl-4-(3,4,5-trimethoxyphenyl)-8-(pyrimidin-2-yl)methoxy-1,2-dihydro-1-oxo-2,7-naphthyridine-3-carboxylic acid methyl ester hydrochloride (T-0156), a new phosphodiesterase type 5 inhibitor, were studied in vitro and in vivo. The inhibitory effects of T-0156 on six phosphodiesterase isozymes isolated from canine tissues were investigated. T-0156 specifically inhibited the hydrolysis of cyclic guanosine monophosphate (cGMP) by phosphodiesterase type 5, at low concentration (IC(50)=0.23 nM), in a competitive manner. T-0156 also inhibited phosphodiesterase type 6 with IC(50) value of 56 nM, which was 240-fold higher than that for inhibition of phosphodiesterase type 5. T-0156 had low potencies against phosphodiesterase types 1, 2, 3, and 4 (IC(50)>10 microM). In the isolated rabbit corpus cavernosum, T-0156 at 10 and 100 nM increased cGMP levels (100 nM T-0156-treated: 6.0+/-1.5 pmol/mg protein, vehicle-treated: 1.1+/-0.4 pmol/mg protein, P<0.05), causing relaxation of the tissue. T-0156 at 1 to 100 nM potentiated the electrical field stimulation-induced relaxation in the isolated rabbit corpus cavernosum in a concentration-dependent manner (100 nM T-0156-treated: 76.9+/-19.8%, vehicle-treated: 12.3+/-10.1%, P<0.05). Intraduodenal administration of T-0156 at 100 to 1000 microg/kg potentiated the pelvic nerve stimulation-induced tumescence in anesthetized dogs (1000 microg/kg T-0156-treated: 279.0+/-38.4%, vehicle-treated: 9.8+/-4.5%, P<0.05). These results suggested that T-0156 enhanced the nitric oxide (NO)/cGMP pathway, probably through blockade of phosphodiesterase type 5 in vitro and in vivo experimental conditions. The present study clearly showed that T-0156 is a potent and highly selective phosphodiesterase type 5 inhibitor, which is a useful tool for pharmacological studies in vitro and in vivo.
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Affiliation(s)
- Hideki Mochida
- Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., 2-2-50, Kawagishi, Toda, Saitama, Japan.
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27
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Inoue H, Yano K, Noto T, Takagi M, Ikeo T, Kikkawa K. Acute and chronic effects of T-1032, a novel selective phosphodiesterase type 5 inhibitor, on monocrotaline-induced pulmonary hypertension in rats. Biol Pharm Bull 2002; 25:1422-6. [PMID: 12419952 DOI: 10.1248/bpb.25.1422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the hemodynamic property of T-1032 (methyl 2-(4-aminophenyl)-1,2-dihydro-1-oxo-7-(2-pyridylmethoxy)-4-(3,4,5-trimethoxy-phenyl)-3-isoquinoline carboxylate sulfate), a novel selective phosphodiesterase type 5 (PDE5) inhibitor, and evaluated the chronic effect of T-1032 on cardiac remodeling and its related death in monocrotaline (MCT)-induced pulmonary hypertensive rats. T-1032 (1, 10, 100 micro g/kg, i.v.) significantly reduced mean arterial pressure (MAP) and right ventricular systolic pressure (RVSP) without a change in heart rate. The change in RVSP was more potent than that in MAP with 1 micro g/kg T-1032 treatment (RVSP: -8.2+/-1.2%, mean arterial pressure: -5.7+/-1.2%), and reductions in RVSP and MAP reached a peak at doses of 1 and 10 micro g/kg, respectively. In contrast, nitroglycerin (0.1, 1, 10 micro g/kg, i.v.) and beraprost (0.1, 1 micro g/kg, i.v.) did not cause a selective reduction in RVSP at any dose. When T-1032 (300 ppm in diet) was chronically administered, it delayed the death, and significantly suppressed right ventricular remodeling (T-1032-treated: 0.318+/-0.021 g, control: 0.401+/-0.013 g, p<0.05). Our present results suggest that T-1032 selectively reduces RVSP, and resulting in the suppression of right ventricular remodeling with a delay of the death in MCT-induced pulmonary hypertensive rats.
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Affiliation(s)
- Hirotaka Inoue
- Discovery Research Laboratory, Tanabe Seiyaku Co, Ltd, Saitama, Japan.
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28
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Rotella DP. Phosphodiesterase 5 inhibitors: current status and potential applications. Nat Rev Drug Discov 2002; 1:674-82. [PMID: 12209148 DOI: 10.1038/nrd893] [Citation(s) in RCA: 226] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Phosphodiesterase enzymes convert cyclic GMP and cyclic AMP to the corresponding nucleotide monophosphates. Phosphodiesterase 5 (PDE5) inhibition is now a widely accepted and efficacious therapeutic option for the treatment of erectile dysfunction in men, as a result of extensive clinical experience with sildenafil and other new PDE5 inhibitors. Research in the field continues at a substantial level to identify new, selective PDE5 inhibitors and to investigate their usefulness and activity in other areas. This review summarizes recent clinical trials with PDE5 inhibitors, advances in medicinal chemistry, and other activities and potential applications of this class of compounds.
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Affiliation(s)
- David P Rotella
- Hopewell Discovery Chemistry, Bristol-Myers Squibb, P.O. Box 5400, Princeton, New Jersey 08543-5400, USA.
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Jernigan NL, Resta TC. Chronic hypoxia attenuates cGMP-dependent pulmonary vasodilation. Am J Physiol Lung Cell Mol Physiol 2002; 282:L1366-75. [PMID: 12003794 DOI: 10.1152/ajplung.00273.2001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic hypoxia (CH) augments endothelium-derived nitric oxide (NO)-dependent pulmonary vasodilation; however, responses to exogenous NO are reduced following CH in female rats. We hypothesized that CH-induced attenuation of NO-dependent pulmonary vasodilation is mediated by downregulation of vascular smooth muscle (VSM) soluble guanylyl cyclase (sGC) expression and/or activity, increased cGMP degradation by phosphodiesterase type 5 (PDE5), or decreased VSM sensitivity to cGMP. Experiments demonstrated attenuated vasodilatory responsiveness to the NO donors S-nitroso-N-acetylpenicillamine and spermine NONOate and to arterial boluses of dissolved NO solutions in isolated, saline-perfused lungs from CH vs. normoxic female rats. In additional experiments, the sGC inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, blocked vasodilation to NO donors in lungs from each group. However, CH was not associated with decreased pulmonary sGC expression or activity as assessed by Western blotting and cGMP radioimmunoassay, respectively. Consistent with our hypothesis, the selective PDE5 inhibitors dipyridamole and T-1032 augmented NO-dependent reactivity in lungs from CH rats, while having little effect in lungs from normoxic rats. However, the attenuated vasodilatory response to NO in CH lungs persisted after PDE5 inhibition. Furthermore, CH similarly inhibited vasodilatory responses to 8-bromoguanosine 3'5'-cyclic monophosphate. We conclude that attenuated NO-dependent pulmonary vasodilation after CH is not likely mediated by decreased sGC expression, but rather by increased cGMP degradation by PDE5 and decreased pulmonary VSM reactivity to cGMP.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases/antagonists & inhibitors
- Animals
- Blotting, Western
- Chronic Disease
- Cyclic GMP/analogs & derivatives
- Cyclic GMP/metabolism
- Cyclic GMP/pharmacology
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Enzyme Inhibitors/pharmacology
- Female
- Guanylate Cyclase
- Hypertrophy, Right Ventricular/etiology
- Hypertrophy, Right Ventricular/physiopathology
- Hypoxia/complications
- Hypoxia/physiopathology
- In Vitro Techniques
- Lung/blood supply
- Lung/metabolism
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/pharmacology
- Nitric Oxide Donors/pharmacology
- Nitroarginine/pharmacology
- Polycythemia/etiology
- Radioimmunoassay
- Rats
- Rats, Sprague-Dawley
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Soluble Guanylyl Cyclase
- Vasodilation/drug effects
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Affiliation(s)
- Nikki L Jernigan
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131-5218, USA.
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Mochida H, Inoue H, Takagi M, Noto T, Yano K, Kikkawa K. Sildenafil and T-1032, phosphodiesterase type 5 inhibitors, showed a different vasorelaxant property in the isolated rat aorta. Eur J Pharmacol 2002; 440:45-52. [PMID: 11959087 DOI: 10.1016/s0014-2999(02)01339-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The vasorelaxant effects of sildenafil and T-1032 [methyl-2-(4-aminophenyl)-1,2-dihydro-1-oxo-7-(2-pyridinylmethoxy)-4-(3,4,5-trimethoxyphenyl)-3-isoquinoline carboxylate sulfate], two phosphodiesterase type 5 inhibitors, were examined in the isolated rat aorta. Sildenafil and T-1032, both of which have almost the same potency and selectivity regarding phosphodiesterase type 5 inhibitory activity, produced a similar, moderate, relaxation at 10(-10) to 10(-7) M (sildenafil: 66.8 +/- 13.7%; T-1032: 77.9 +/- 10.8% at 10(-7) M). However, sildenafil, but not T-1032, produced further relaxation at the higher concentrations (sildenafil: 102.0 +/- 0.6%; T-1032: 81.0 +/- 7.2% at 10(-4) M, P < 0.05). Sildenafil also produced a more potent relaxation than did T-1032 at the high concentrations (10(-5) and 10(-4) M) in endothelium-denuded aortic rings and in the presence of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor (3 x 10(-4) M). Moreover, the high concentrations of sildenafil, but not of T-1032, caused a rightward shift of the concentration-response curve for calcium chloride in K(+)-depolarized endothelium-denuded preparations. In the ligand binding assay for the L-type Ca(2+) channels, the affinities of sildenafil at 10(-5) M for binding sites of nitrendipine and (--)-desmethoxyverapamil [(--)- D888] (35.2 +/- 3.3% and 35.8 +/- 1.9%, respectively) were higher than those of T-1032 (11.8 +/- 4.0% and -13.1 +/- 1.3%, respectively, P < 0.05). Regarding cyclic nucleotide levels, both phosphodiesterase type 5 inhibitors increased cGMP levels at 10(-6) M. However, sildenafil, but not T-1032, further increased cGMP levels at the higher concentrations (sildenafil: 15.7 +/- 2.7 pmol/mg protein; T-1032: 5.6 +/- 0.6 pmol/mg protein at 10(-4) M, P < 0.05). These results suggested that high concentrations of sildenafil had additional vasorelaxant properties through mechanisms other than phosphodiesterase type 5 inhibition. Sildenafil-induced relaxation appears to be due to inhibition of the external Ca(2+)-dependent cascade for contraction and/or to an increase in cGMP levels. In contrast, T-1032 only showed a vasorelaxant property due to phosphodiesterase type 5 inhibition. In conclusion, T-1032 appears to be a specific phosphodiesterase type 5 inhibitor compared with sildenafil and a useful compound to examine the physiological function of phosphodiesterase type 5.
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MESH Headings
- 3',5'-Cyclic-GMP Phosphodiesterases
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiology
- Binding, Competitive
- Calcium Channels, L-Type/metabolism
- Calcium Chloride/pharmacology
- Cyclic AMP/metabolism
- Cyclic GMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 5
- Dose-Response Relationship, Drug
- Endothelium, Vascular/physiology
- In Vitro Techniques
- Isoquinolines/metabolism
- Isoquinolines/pharmacology
- Male
- NG-Nitroarginine Methyl Ester/pharmacology
- Phorbol 12,13-Dibutyrate/pharmacology
- Phosphodiesterase Inhibitors/pharmacology
- Phosphoric Diester Hydrolases/drug effects
- Piperazines/metabolism
- Piperazines/pharmacology
- Purines
- Pyridines/metabolism
- Pyridines/pharmacology
- Radioligand Assay
- Rats
- Rats, Wistar
- Sildenafil Citrate
- Sulfones
- Vasodilation/drug effects
- Vasodilator Agents/pharmacology
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Affiliation(s)
- Hideki Mochida
- Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., 2-2-50, Kawagishi, Toda, Saitama 335-8505, Japan.
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Chapter 6. Phosphodiesterase 5 inhibitors. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2002. [DOI: 10.1016/s0065-7743(02)37007-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Hirose R, Okumura H, Yoshimatsu A, Irie J, Onoda Y, Nomoto Y, Takai H, Ohno T, Ichimura M. KF31327, a new potent and selective inhibitor of cyclic nucleotide phosphodiesterase 5. Eur J Pharmacol 2001; 431:17-24. [PMID: 11716838 DOI: 10.1016/s0014-2999(01)01422-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effects of KF31327 (3-ethyl-8-[2-(4-hydroxymethylpiperidino)benzylamino]-2,3-dihydro-1H-imidazo[4,5-g]quinazoline-2-thione dihydrochloride) on phosphodiesterase 5 (cyclic GMP-specific phosphodiesterase) activity and platelet aggregation were investigated and compared with those of sildenafil, a well-known phosphodiesterase 5 inhibitor. KF31327 inhibited phosphodiesterase 5 from canine trachea (K(i)=0.16 nM) more potently than sildenafil (K(i)=7.2 nM). The kinetic analysis revealed that KF31327 was a non-competitive inhibitor. In the presence of nitroglycerin (nitric oxide generator), both compounds inhibited the collagen-induced aggregation of rabbit platelets at less than 0.1 microM, augmenting intracellular cyclic GMP level without affecting cyclic AMP. In contrast, in the absence of nitroglycerin, a higher concentration (10 microM) of KF31327 was required to inhibit platelet aggregation and increased both cyclic nucleotide levels. However, 10 microM sildenafil did not affect aggregation despite elevation of cyclic GMP comparable to that in the presence of nitroglycerin. These results indicate that in the presence of nitroglycerin, the inhibition of platelet aggregation by KF31327 is due to the elevation of cyclic GMP, whereas the mechanism underlying the inhibition without nitroglycerin might be related to a rise in intracellular cyclic AMP.
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Affiliation(s)
- R Hirose
- Pharmaceutical Research Institute, Kyowa Hakko Kogyo Co., Ltd., 1188 Shimotogari, Nagaizumi-cho, 411-8731, Shizuoka, Japan
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Inoue H, Yano K, Ikeo T, Noto T, Kikkawa K. T-1032, a novel specific phosphodiesterase type 5 inhibitor, increases venous compliance in anesthetized rats. Eur J Pharmacol 2001; 422:109-14. [PMID: 11430921 DOI: 10.1016/s0014-2999(01)01044-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Nitric oxide (NO) donors including organic nitrates dilate capacitance vessels. As inhibition of phosphodiesterase type 5 results in the accumulation of guanosine 3'5'-cyclic monophosphate (cGMP), specific phosphodiesterase type 5 inhibitors are expected to have a vasodilator property similar to that of NO donors. To test this hypothesis, we examined the effect of methyl2-(4-aminophenyl)-1,2-dihydro-1-oxo-7-(2-pyridinylmethoxy)-4-(3,4,5-trimethoxyphenyl)-3-isoquinoline carboxylate sulfate (T-1032), a novel specific phosphodiesterase type 5 inhibitor, on mean arterial pressure and mean circulatory filling pressure (an index of venodilation) compared with that of nitroglycerin and diltiazem in mecamylamine- and noradrenaline-treated anesthetized rats. Intravenous infusion of T-1032 (0.1, 1, 10 microg/kg/min) dose-dependently decreased mean arterial pressure (-3.8+/-0.3%, -9.1+/-0.8%, -16.8+/-1.5% at doses of 0.1, 1 and 10 microg/kg/min, respectively) and mean circulatory filling pressure (-6.1+/-0.9%, -12.5+/-0.7%, -18.6+/-3.0% at doses of 0.1, 1 and 10 microg/kg/min, respectively). The mean circulatory filling pressure-mean arterial pressure relationship revealed that T-1032 had a selective action on the mean circulatory filling pressure compared with diltiazem (10, 100 microg/kg/min) and a similar or more selective effect than nitroglycerin (0.3, 3 and 30 microg/kg/min). In the next study, we calculated venous compliance and unstressed volume from the mean circulatory filling pressure-volume relationship. Intravenous infusion of T-1032 (3 microg/kg/min) increased venous compliance (3.35+/-0.40 in T-1032 vs. 2.31+/-0.15 ml/kg/mm Hg in vehicle, P<0.05) without changing the unstressed volume (37.2+/-2.80 in T-1032 vs. 42.6+/-2.37 ml/kg in vehicle, P>0.05). It was concluded that T-1032 increased venous capacitance by increasing venous compliance, and that this selective phosphodiesterase type 5 inhibitor appeared to have a different vasodilator action from that of an NO donor and a Ca(2+) channel antagonist in that it had a selective action on the mean circulatory filling pressure.
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Affiliation(s)
- H Inoue
- Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., 2-2-50, Kawagishi Toda, Saitama, 335-8505, Japan.
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Takagi M, Mochida H, Noto T, Yano K, Inoue H, Ikeo T, Kikkawa K. Pharmacological profile of T-1032, a novel specific phosphodiesterase type 5 inhibitor, in isolated rat aorta and rabbit corpus cavernosum. Eur J Pharmacol 2001; 411:161-168. [PMID: 11137871 DOI: 10.1016/s0014-2999(00)00907-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study was designed to examine the pharmacological properties of T-1032 (methyl-2-(4-aminophenyl)-1,2-dihydro-1-oxo-7-(2-pyridinylmethoxy)-4-(3,4,5-trimethoxyphenyl)-3-isoquinoline carboxylate sulfate), a novel phosphodiesterase type 5 inhibitor, in isolated rat aorta and rabbit corpus cavernosum. T-1032 (3x10(-11) to 3x10(-7) M) caused an endothelium-dependent relaxation in the isolated rat aorta precontracted with phenylephrine, and the relaxation was accompanied by an increase in cGMP but not cAMP levels. The T-1032-induced relaxation was attenuated by N(G)-nitro-L-arginine methyl ester (L-NAME) (10(-3) M), a nitric oxide (NO) synthase inhibitor, or 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ) (10(-5) M), a guanylyl cyclase inhibitor. T-1032 (10(-9), 10(-8) M) produced a potentiation of the relaxation induced by sodium nitroprusside, but not of the relaxation induced by isoproterenol. In the isolated rabbit corpus cavernosum precontracted with phenylephrine, the electrical field stimulation-induced relaxation was attenuated by treatment with tetrodotoxin (10(-6) M) as well as L-NAME (10(-4) M). The L-NAME-inhibited relaxation was restored by treatment with L-arginine (5x10(-4) M). T-1032 (10(-9) to 10(-6) M) and sildenafil (10(-9) to 10(-6) M) produced a potentiation of the electrical field stimulation-induced relaxation as well as a decrease in basal tension in a concentration-dependent manner. It was concluded that T-1032 had potentiating effects on the NO/cGMP signaling pathway in isolated tissues, probably through specific blockade of phosphodiesterase type 5. T-1032 would be a useful compound to examine the physiologic functions of phosphodiesterase type 5 in mammalian tissues.
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Affiliation(s)
- M Takagi
- Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., 2-2-50, Kawagishi, Saitama 335-8505, Toda, Japan
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