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Sobrano Fais R, Menezes da Costa R, Carvalho Mendes A, Mestriner F, Comerma‐Steffensen SG, Tostes RC, Simonsen U, Silva Carneiro F. NLRP3 activation contributes to endothelin-1-induced erectile dysfunction. J Cell Mol Med 2022; 27:1-14. [PMID: 36515571 PMCID: PMC9806301 DOI: 10.1111/jcmm.17463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 05/30/2022] [Accepted: 06/04/2022] [Indexed: 12/15/2022] Open
Abstract
In the present study, we hypothesized that endothelin (ET) receptors (ETA and ETB ) stimulation, through increased calcium and ROS formation, leads to Nucleotide Oligomerization Domain-Like Receptor Family, Pyrin Domain Containing 3 (NLRP3) activation. Intracavernosal pressure (ICP/MAP) was measured in C57BL/6 (WT) mice. Functional and immunoblotting assays were performed in corpora cavernosa (CC) strips from WT, NLRP3-/- and caspase-/- mice in the presence of ET-1 (100 nM) and vehicle, MCC950, tiron, BAPTA AM, BQ123, or BQ788. ET-1 reduced the ICP/MAP in WT mice, and MCC950 prevented the ET-1 effect. ET-1 decreased CC ACh-, sodium nitroprusside (SNP)-induced relaxation, and increased caspase-1 expression. BQ123 an ETA receptor antagonist reversed the effect. The ETB receptor antagonist BQ788 also reversed ET-1 inhibition of ACh and SNP relaxation. Additionally, tiron, BAPTA AM, and NLRP3 genetic deletion prevented the ET-1-induced loss of ACh and SNP relaxation. Moreover, BQ123 diminished CC caspase-1 expression, while BQ788 increased caspase-1 and IL-1β levels in a concentration-dependent manner (100 nM-10 μM). Furthermore, tiron and BAPTA AM prevented ET-1-induced increase in caspase-1. In addition, BAPTA AM blocked ET-1-induced ROS generation. In conclusion, ET-1-induced erectile dysfunction depends on ETA - and ETB -mediated activation of NLRP3 in mouse CC via Ca2+ -dependent ROS generation.
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Affiliation(s)
- Rafael Sobrano Fais
- Department of Pharmacology, Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoBrazil,Division of Pulmonary, Critical Care, and Sleep MedicineNational Jewish HealthDenverColoradoUSA
| | | | - Allan Carvalho Mendes
- Department of Pharmacology, Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoBrazil
| | - Fabíola Mestriner
- Department of Pharmacology, Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoBrazil
| | | | - Rita C. Tostes
- Department of Pharmacology, Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoBrazil
| | - Ulf Simonsen
- Department of Biomedicine, Pulmonary and Cardiovascular PharmacologyAarhus UniversityAarhusDenmark
| | - Fernando Silva Carneiro
- Department of Pharmacology, Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoBrazil
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Fujimoto K, Hashimoto D, Kashimada K, Kumegawa S, Ueda Y, Hyuga T, Hirashima T, Inoue N, Suzuki K, Hara I, Asamura S, Yamada G. A visualization system for erectile vascular dynamics. Front Cell Dev Biol 2022; 10:1000342. [PMID: 36313553 PMCID: PMC9615422 DOI: 10.3389/fcell.2022.1000342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Erection is an essential process which requires the male penis for copulation. This copulatory process depends on the vascular dynamic regulation of the penis. The corpus cavernosum (CC) in the upper (dorsal) part of the penis plays a major role in regulating blood flow inside the penis. When the CC is filled with blood, the sinusoids, including micro-vessels, dilate during erection. The CC is an androgen-dependent organ, and various genital abnormalities including erectile dysfunction (ED) are widely known. Previous studies have shown that androgen deprivation by castration results in significantly decreased smooth muscles of the CC. Experimental works in erectile biology have previously measured intracavernosal penile pressure and mechanical tension. Such reports analyze limited features without assessing the dynamic aspects of the erectile process. In the current study, we established a novel explant system enabling direct visual imaging of the sinusoidal lumen to evaluate the dynamic movement of the cavernous space. To analyze the alternation of sinusoidal spaces, micro-dissected CC explants by patent blue dye injection were incubated and examined for their structural alternations during relaxation/contraction. The dynamic process of relaxation/contraction was analyzed with various external factors administered to the CC. The system enabled the imaging of relaxation/contraction of the lumens of the sinusoids and the collagen-containing tissues. Histological analysis on the explant system also showed the relaxation/contraction. Thus, the system mimics the regulatory process of dynamic relaxation/contraction in the erectile response. The current system also enabled evaluating the erectile pathophysiology. In the current study, the lumen of sinusoids relaxed/contracted in castrated mice similarly with normal mice. These results suggested that the dynamic erectile relaxation/contraction process was similarly retained in castrated mice. However, the system also revealed decreased duration time of erection in castrated mice. The current study is expected to promote further understanding of the pathophysiology of ED, which will be useful for new treatments in the future. Hence, the current system provides unique information to investigate the novel regulations of erectile function, which can provide tools for analyzing the pathology of ED.
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Affiliation(s)
- Kota Fujimoto
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Wakayama, Japan
- Department of Plastic and Reconstructive Surgery, Wakayama Medical University, Wakayama, Japan
| | - Daiki Hashimoto
- Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Kenichi Kashimada
- Department of Pediatrics and Developmental Biology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shinji Kumegawa
- Department of Plastic and Reconstructive Surgery, Wakayama Medical University, Wakayama, Japan
| | - Yuko Ueda
- Department of Urology, Wakayama Medical University, Wakayama, Japan
| | - Taiju Hyuga
- Department of Pediatric Urology, Children’s Medical Center Tochigi, Jichi Medical University, Tochigi, Japan
| | - Tsuyoshi Hirashima
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Norimitsu Inoue
- Department of Molecular Genetics, Wakayama Medical University, Wakayama, Japan
| | - Kentaro Suzuki
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, Japan
| | - Isao Hara
- Department of Urology, Wakayama Medical University, Wakayama, Japan
| | - Shinichi Asamura
- Department of Plastic and Reconstructive Surgery, Wakayama Medical University, Wakayama, Japan
| | - Gen Yamada
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Wakayama, Japan
- Department of Plastic and Reconstructive Surgery, Wakayama Medical University, Wakayama, Japan
- *Correspondence: Gen Yamada,
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Torres Crigna A, Link B, Samec M, Giordano FA, Kubatka P, Golubnitschaja O. Endothelin-1 axes in the framework of predictive, preventive and personalised (3P) medicine. EPMA J 2021; 12:265-305. [PMID: 34367381 PMCID: PMC8334338 DOI: 10.1007/s13167-021-00248-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 06/11/2021] [Indexed: 02/07/2023]
Abstract
Endothelin-1 (ET-1) is involved in the regulation of a myriad of processes highly relevant for physical and mental well-being; female and male health; in the modulation of senses, pain, stress reactions and drug sensitivity as well as healing processes, amongst others. Shifted ET-1 homeostasis may influence and predict the development and progression of suboptimal health conditions, metabolic impairments with cascading complications, ageing and related pathologies, cardiovascular diseases, neurodegenerative pathologies, aggressive malignancies, modulating, therefore, individual outcomes of both non-communicable and infectious diseases such as COVID-19. This article provides an in-depth analysis of the involvement of ET-1 and related regulatory pathways in physiological and pathophysiological processes and estimates its capacity as a predictor of ageing and related pathologies,a sensor of lifestyle quality and progression of suboptimal health conditions to diseases for their targeted preventionand as a potent target for cost-effective treatments tailored to the person.
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Affiliation(s)
- Adriana Torres Crigna
- Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Barbara Link
- Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Marek Samec
- Clinic of Obstetrics and Gynecology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Frank A. Giordano
- Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Peter Kubatka
- Department of Medical Biology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 036 01 Martin, Slovakia
| | - Olga Golubnitschaja
- Predictive, Preventive and Personalised (3P) Medicine, Department of Radiation Oncology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
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de Oliveira AA, Nunes KP. Hypertension and Erectile Dysfunction: Breaking Down the Challenges. Am J Hypertens 2021; 34:134-142. [PMID: 32866225 DOI: 10.1093/ajh/hpaa143] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 07/15/2020] [Accepted: 08/29/2020] [Indexed: 02/07/2023] Open
Abstract
A diagnostic of hypertension increases the risk of erectile dysfunction (ED); likewise, ED can be an early sign of hypertension. In both cases, there is evidence that endothelial dysfunction is a common link between the 2 conditions. During hypertension, the sustained and widespread release of procontractile factors (e.g., angiotensin II, endothelin 1, and aldosterone) impairs the balance between vasoconstrictors and vasodilators and, in turn, detrimentally impacts vascular and erectile structures. This prohypertensive state associates with an enhancement in the generation of reactive oxygen species, which is not compensated by internal antioxidant mechanisms. Recently, the innate immune system, mainly via Toll-like receptor 4, has also been shown to actively contribute to the pathophysiology of hypertension and ED not only by inducing oxidative stress but also by sustaining a low-grade inflammatory state. Furthermore, some drugs used to treat hypertension can cause ED and, consequently, reduce compliance with the prescribed pharmacotherapy. To break down these challenges, in this review, we focus on discussing the well-established as well as the emerging mechanisms linking hypertension and ED with an emphasis on the signaling network of the vasculature and corpora cavernosa, the vascular-like structure of the penis.
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Affiliation(s)
- Amanda Almeida de Oliveira
- Laboratory of Vascular Physiology, Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, Florida, USA
| | - Kenia Pedrosa Nunes
- Laboratory of Vascular Physiology, Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, Florida, USA
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Leitolis A, Crestani S, Linder ÁE, da Silva-Santos JE. High-Salt Intake Reduces Apomorphine-Induced Penile Erection and Increases Neurally Mediated Contractile Responses of the Cavernosal Smooth Muscle in Rats. Am J Hypertens 2019; 32:1206-1213. [PMID: 31584631 DOI: 10.1093/ajh/hpz142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/09/2019] [Accepted: 09/02/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND This study was designed to evaluate whether overconsumption of NaCl, a well-known risk factor for hypertension, leads to erectile dysfunction in rodents. METHODS Male Wistar rats received regular chow (control group) or 4% NaCl chow for 24 weeks and were subjected to blood pressure measurement and apomorphine-induced erection. Moreover, cavernosal strips from both the control and 4% NaCl groups were evaluated in organ baths. RESULTS Animals subjected to 4% NaCl chow did not develop hypertension but presented a significant reduction in the total number of erections following apomorphine administration as compared with the control group. The addition of high KCl or phenylephrine resulted in similar contractile responses in the corpus cavernosal strips from both the control and 4% NaCl groups. However, electrical field stimulation-induced contraction was significantly enhanced in cavernosal strips from animals exposed to 4% NaCl. Incubation of Y-27632, but not of atropine and Nω-nitro-l-arginine methyl ester (L-NAME), entirely prevented the potentiation of the contractile responses evoked by electrical stimulation. The enhanced contractile responses evoked by electrical stimulation found in the high-salt group were also avoided in the absence of extracellular calcium. Concentration-response curves of CaCl2 revealed augmented contractility in response to extracellular calcium in cavernosal strips from the 4% NaCl-treated rats, compared with control samples. CONCLUSIONS A high-salt diet alone rendered the animals less responsive to apomorphine-induced penile erection and enhanced neurally mediated contractile responses in the corpus cavernosum, a clear indication that overconsumption of sodium can lead to erectile dysfunction even without the development of hypertension.
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Affiliation(s)
- Amanda Leitolis
- Laboratory of Cardiovascular Biology, Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Sandra Crestani
- Laboratory of Cardiovascular Biology, Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Áurea Elizabeth Linder
- Laboratory of Cardiovascular Biology, Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - José Eduardo da Silva-Santos
- Laboratory of Cardiovascular Biology, Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
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ALTUNÖREN O, ERKEN E, GÜNGÖR Ö, YAVUZ YC. Hipertansiyon ve Erektil Disfonksiyon. KAHRAMANMARAŞ SÜTÇÜ İMAM ÜNIVERSITESI TIP FAKÜLTESI DERGISI 2019. [DOI: 10.17517/ksutfd.477511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Stallmann-Jorgensen I, Ogbi S, Szasz T, Webb RC. A Toll-Like Receptor 1/2 Agonist Augments Contractility in Rat Corpus Cavernosum. J Sex Med 2015; 12:1722-31. [PMID: 26234560 DOI: 10.1111/jsm.12960] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Activation of the innate immune Toll-like receptor 2 (TLR2) initiates inflammation and has been implicated in vascular dysfunction. Increased contraction and decreased relaxation responses in the penile vasculature lead to erectile dysfunction, a condition associated with inflammation. However, whether TLR2 activation plays a role in penile vascular function has not been established. AIM We hypothesized that activation of the TLR 1/2 heterodimer (TLR1/2) augments contractile and impairs relaxation responses of corpus cavernosum and that these perturbations of vascular function are mediated by low nitric oxide (NO) availability and enhanced activity of the RhoA/Rho-kinase pathway. METHODS Contraction and relaxation responses were measured in rat cavernosal strips using a myograph after incubation with a TLR1/2-activating ligand Pam3 CSK4 (Pam3), the TLR1/2 inhibitor CuCPT 22 (CuCPT), and inhibitors of NO synthase (LNAME) and Rho-kinase (Y27632). TLR2 protein expression was assessed by immunohistochemistry. MAIN OUTCOME MEASURES Cumulative concentration response curves, sensitivity (pEC50), and maximal response (Emax ) of cavernosal strips to vasodilatory and vasocontractile agonists were compared between treatments. RESULTS Pam3-treated cavernosal strips exhibited greater pEC50 and higher Emax to phenylephrine (PE) than control tissues. Inhibition of NO synthase increased Emax to PE in Pam3-treated cavernosal strips. Pam3 treatment reduced relaxation to Y27632 compared with control tissues. Inhibition of TLR1/2 activation with CuCPT returned the augmented contraction to PE and the decreased relaxation to Y27632 of Pam3-treated cavernosal strips to control values. CONCLUSIONS The TLR1/2 heterodimer mediates augmented contraction and reduced relaxation in rat cavernosal strips. Thus, TLR1/2 activation antagonizes vascular responses crucial for normal erectile function and implicates immune activation in vasculogenic erectile dysfunction. Immune signaling via TLR2 may offer novel targets for treating inflammation-mediated vascular dysfunction in the penis.
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Affiliation(s)
| | - Safia Ogbi
- Department of Physiology, Georgia Regents University, Augusta, GA, USA
| | - Theodora Szasz
- Department of Physiology, Georgia Regents University, Augusta, GA, USA
| | - R Clinton Webb
- Department of Physiology, Georgia Regents University, Augusta, GA, USA
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Silva FH, Alexandre EC, Calmasini FB, Calixto MC, Antunes E. Treatment With Metformin Improves Erectile Dysfunction in a Murine Model of Obesity Associated With Insulin Resistance. Urology 2015. [PMID: 26199165 DOI: 10.1016/j.urology.2015.04.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate the effects of treatment with metformin on a murine model of obesity-associated erectile dysfunction. MATERIAL AND METHODS C57BL/6 male mice were fed for 10 weeks with standard chow or high-fat diet. Lean and obese mice were treated with the insulin sensitizer metformin (300 mg/kg/day, 2 weeks). Intracavernosal pressure (ICP) and in vitro corpus cavernosum (CC) relaxations to both acetylcholine and electrical field stimulation, as well as phenylephrine-induced contractions, were obtained. Levels of cyclic guanosine monophosphate in CC were detected by enzyme immunoassay. RESULTS High-fat-fed mice exhibited higher body weight and insulin resistance. Cavernous nerve stimulation caused frequency-dependent ICP increases, which were significantly lower in obese compared with lean mice (P <.05). Two-week therapy with metformin reversed the decreased ICP in obese group. The maximal response to acetylcholine in CC was 35% lower (P <.05) in the obese compared to the lean group, which were restored by metformin treatment. Likewise, the impaired electrical field stimulation-induced CC relaxations in obese mice were also partly restored by metformin. Contractile responses to phenylephrine were significantly greater (P <.05) in obese compared to lean mice, which were fully restored by metformin. Basal and stimulated cyclic guanosine monophosphate productions in the erectile tissues were significantly lower (P <.05) in the obese group, an effect fully restored by metformin. CONCLUSION Treatment with metformin restored the erectile function in obese mice, through improvement of in vitro endothelial and nitrergic cavernosal relaxations. Therefore, use of metformin may be a good pharmacologic approach to treat insulin resistance-associated erectile dysfunction.
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Affiliation(s)
- Fábio H Silva
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil.
| | - Eduardo C Alexandre
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil
| | - Fabiano B Calmasini
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil
| | - Marina C Calixto
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil
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Silva FH, Lanaro C, Leiria LO, Rodrigues RL, Davel AP, Claudino MA, Toque HA, Antunes E. Oxidative stress associated with middle aging leads to sympathetic hyperactivity and downregulation of soluble guanylyl cyclase in corpus cavernosum. Am J Physiol Heart Circ Physiol 2014; 307:H1393-400. [DOI: 10.1152/ajpheart.00708.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Impairment of nitric oxide (NO)-mediated cavernosal relaxations in middle age contributes to erectile dysfunction. However, little information is available about the alterations of sympathetic neurotransmission and contraction in erectile tissue at middle age. This study aimed to evaluate the alterations of the contractile machinery associated with tyrosine hydroxylase (TH) in rat corpus cavernosum (RCC) at middle age, focusing on the role of superoxide anion. Male Wistar young (3.5-mo) and middle-aged (10-mo) rats were used. Electrical-field stimulation (EFS)- and phenylephrine-induced contractions were obtained in RCC strips. Levels of reactive-oxygen species (ROS) and TH mRNA expression, as well as protein expressions for α1/β1-subunits of soluble guanylyl cyclase (sGC), in RCC were evaluated. The neurogenic contractile responses elicited by EFS (4–32 Hz) were greater in RCC from the middle-aged group that was accompanied by elevated TH mRNA expression ( P < 0.01). Phenylephrine-induced contractions were also greater in the middle-aged group. A 62% increase in ROS generation in RCC from middle-aged rats was observed. The mRNA expression for the α1A-adrenoceptor remained unchanged among groups. Protein levels of α1/β1-sGC subunits were decreased in RCC from the middle-aged compared with young group. The NADPH oxidase inhibitor apocynin (85 mg·rat−1·day−1, 4 wk) fully restored the enhanced ROS production, TH mRNA expressions, and α1/β1-subunit sGC expression, indicating that excess of superoxide anion plays a major role in the sympathetic hyperactivity and hypercontractility in erectile tissue at middle age. Reduction of oxidative stress by dietary antioxidants may be an interesting approach to treat erectile dysfunction in aging population.
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Affiliation(s)
- Fábio H. Silva
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Carolina Lanaro
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Luiz Osório Leiria
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Renata Lopes Rodrigues
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Ana Paula Davel
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Mário A. Claudino
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
| | - Haroldo A. Toque
- Department of Pharmacology and Toxicology, Georgia Health Sciences University, Augusta, Georgia
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences and Department of Anatomy, Cellular Biology, Physiology and Biophysics, Institute of Biology, University of Campinas, Campinas, São Paulo, Brazil; and
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Toque HA, Caldwell RW. New approaches to the design and discovery of therapies to prevent erectile dysfunction. Expert Opin Drug Discov 2014; 9:1447-69. [DOI: 10.1517/17460441.2014.949234] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Decaluwé K, Pauwels B, Boydens C, Van de Voorde J. Treatment of erectile dysfunction: new targets and strategies from recent research. Pharmacol Biochem Behav 2013; 121:146-57. [PMID: 24291648 DOI: 10.1016/j.pbb.2013.11.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 11/18/2013] [Indexed: 12/15/2022]
Abstract
In recent years, research on penile erection has increasingly been centered on the molecular mechanisms involved. Major progress has been made in the field and at present a whole number of neurotransmitters, chemical effectors, growth factors, second-messenger molecules, ions, intercellular proteins, and hormones have been characterized as components of the complex process of erection. This knowledge has led to the discovery of several new therapeutic targets and multiple medical approaches for the treatment of erectile dysfunction (ED). This review focuses on the progress made in this field within the last few years.
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Affiliation(s)
- K Decaluwé
- Department of Pharmacology, Ghent University, Ghent, Belgium
| | - B Pauwels
- Department of Pharmacology, Ghent University, Ghent, Belgium
| | - C Boydens
- Department of Pharmacology, Ghent University, Ghent, Belgium
| | - J Van de Voorde
- Department of Pharmacology, Ghent University, Ghent, Belgium.
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Labazi H, Wynne BM, Tostes R, Webb RC. Metformin treatment improves erectile function in an angiotensin II model of erectile dysfunction. J Sex Med 2013; 10:2154-64. [PMID: 23889981 DOI: 10.1111/jsm.12245] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
INTRODUCTION Increased angiotensin II (AngII) levels cause hypertension, which is a major risk factor for erectile dysfunction (ED). Studies have demonstrated that increased AngII levels in penile tissue are associated with ED. A recent study showed that metformin treatment restored nitric oxide synthase (NOS) protein expression in penile tissue in obese rats; however, whether metformin treatment can be beneficial and restore erectile function in a model of ED has not yet been established. AIM The goal of this study was to test the hypothesis that AngII induces ED by means of increased corpus cavernosum contraction, and that metformin treatment will reverse ED in AngII-treated rats. METHODS Male Sprague-Dawley rats were implanted with mini-osmotic pumps containing saline or AngII (70 ng/minute, 28 days). Animals were then treated with metformin or vehicle during the last week of AngII infusion. MAIN OUTCOME MEASURES Intracavernosal pressure; corpus cavernosum contraction and relaxation; nNOS protein expression; extracellular signal-regulated kinase (ERK1/2), AMP-activated protein kinase (AMPK), and eNOS protein expression and phosphorylation. RESULTS AngII-induced ED was accompanied with an increase in corpus cavernosum contractility, decreased nitrergic relaxation, and increased ERK1/2 phosphorylation. Metformin treatment improved erectile function in the AngII-treated rats by reversing the increased contraction and decreased relaxation. Metformin treatment also resulted in an increase in eNOS phosphorylation at ser1177. CONCLUSIONS Metformin treatment increased eNOS phosphorylation and improved erectile function in AngII hypertensive rats by reestablishing normal cavernosal smooth muscle tone.
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Affiliation(s)
- Hicham Labazi
- Georgia Health Sciences University, Physiology Department, Augusta, GA, USA
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Cellek S, Bivalacqua TJ, Burnett AL, Chitaley K, Lin C. Common Pitfalls in Some of the Experimental Studies in Erectile Function and Dysfunction: A Consensus Article. J Sex Med 2012; 9:2770-84. [DOI: 10.1111/j.1743-6109.2012.02916.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
PURPOSE OF REVIEW Erectile dysfunction is recognized as a quality-of-life disorder that needs to be treated. Currently, it is estimated to affect as many as 30 million American men. Thirty percent of hypertensive patients complain of erectile dysfunction. The understanding of common mechanisms involved in the cause of erectile dysfunction associated with hypertension, and the investigation of antihypertensive drugs that impact erectile dysfunction, will provide important tools toward identifying new therapeutic targets that will improve the quality of life for patients in these conditions. RECENT FINDINGS Hypertension and erectile dysfunction are closely intertwined diseases, which have endothelial dysfunction as a common base. During hypertension and/or erectile dysfunction, disturbance of endothelium-derived factors can lead to an increase in vascular smooth muscle (VSM) contraction. Hypertension can lead to erectile dysfunction as a consequence of high blood pressure (BP) or due to antihypertensive treatment. However, growing evidence suggests erectile dysfunction is an early sign for hypertension. Also, some phosphodiesterase-5 inhibitors used to treat erectile dysfunction can improve BP, but the link between these conditions has not been totally understood. SUMMARY This review will discuss the interplay between hypertension and erectile dysfunction, exploring newest insights regarding hypertension-associated erectile dysfunction, as well as the effect of antihypertensive drugs in erectile dysfunction patients.
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Filgueira F, Lobato N, DosSantos R, Oliveira M, Akamine E, Tostes R, Fortes Z, Carvalho M. Endogenous testosterone increases leukocyte–endothelial cell interaction in spontaneously hypertensive rats. Life Sci 2012; 90:689-94. [DOI: 10.1016/j.lfs.2012.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 02/29/2012] [Accepted: 03/16/2012] [Indexed: 11/17/2022]
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Giachini FR, Lima VV, Hannan JL, Carneiro FS, Webb RC, Tostes RC. STIM1/Orai1-mediated store-operated Ca2+ entry: the tip of the iceberg. Braz J Med Biol Res 2011; 44:1080-7. [PMID: 22002090 DOI: 10.1590/s0100-879x2011007500133] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 09/05/2011] [Indexed: 11/22/2022] Open
Abstract
Highly efficient mechanisms regulate intracellular calcium (Ca2+) levels. The recent discovery of new components linking intracellular Ca2+ stores to plasma membrane Ca2+ entry channels has brought new insight into the understanding of Ca2+ homeostasis. Stromal interaction molecule 1 (STIM1) was identified as a Ca2+ sensor essential for Ca2+ store depletion-triggered Ca2+ influx. Orai1 was recognized as being an essential component for the Ca2+ release-activated Ca2+ (CRAC) channel. Together, these proteins participate in store-operated Ca2+ channel function. Defective regulation of intracellular Ca2+ is a hallmark of several diseases. In this review, we focus on Ca2+ regulation by the STIM1/Orai1 pathway and review evidence that implicates STIM1/Orai1 in several pathological conditions including cardiovascular and pulmonary diseases, among others.
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Affiliation(s)
- F R Giachini
- Department of Physiology, Georgia Heath Science University, Augusta, GA, USA.
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17
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The promise of inhibition of smooth muscle tone as a treatment for erectile dysfunction: where are we now? Int J Impot Res 2011; 24:49-60. [PMID: 21975566 DOI: 10.1038/ijir.2011.49] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ten years ago, the inhibition of Rho kinase by intracavernosal injection of Y-27632 was found to induce an erectile response. This effect did not require activation of nitric oxide-mediated signaling, introducing a novel target pathway for the treatment of erectile dysfunction (ED), with potential added benefit in cases where nitric oxide bioavailability is attenuated (and thus phosphodiesterase type 5 (PDE5) inhibitors are less efficacious). Rho-kinase antagonists are currently being developed and tested for a wide range of potential uses. The inhibition of this calcium-sensitizing pathway results in blood vessel relaxation. It is also possible that blockade of additional smooth muscle contractile signaling mechanisms may have the same effect. In this review, we conducted an extensive search of pertinent literature using PUBMED. We have outlined the various pathways involved in the maintenance of penile smooth muscle tone and discussed the current potential benefit for the pharmacological inhibition of these targets for the treatment of ED.
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Abstract
INTRODUCTION A role for cytokines in the pathophysiology of erectile dysfunction (ED) has emerged. Cytokines induce genes that synthesize other peptides in the cytokine family and several mediators, such as prostanoids, leukotrienes, nitric oxide, bradykinin, reactive oxygen species, and platelet-activating factor, all of which can affect vascular function. Consistent with the fact that the cavernosal tissue is a complex extension of the vasculature, risk factors that affect the vasculature have been shown to affect cavernosal function as well. Accordingly, the penile tissue has been recognized as an early sentinel for atherosclerosis that underlies coronary artery disease and cardiovascular diseases (CVD). AIM To review the literature pertaining to the role of tumor necrosis factor-alpha (TNF-α) in ED. METHODS PubMed search for pertinent publications on the role of cytokines, particularly TNF-α, in CVD and ED. MAIN OUTCOME MEASURES Clinical and experimental evidence demonstrates that TNF-α may play a role in ED. RESULTS TNF-α has been shown to play an important role in CVD, mainly due to its direct effects on the vasculature. In addition, high levels of TNF-α were demonstrated in patients with ED. In this review, we present a short description of the physiology of erection and the cytokine network. We focus on vascular actions of TNF-α that support a role for this cytokine as a potential candidate in the pathophysiology of ED, particularly in the context of CVD. A brief overview of its discovery, mechanisms of synthesis, receptors, and its main actions on the systemic and penile vasculature is also presented. CONCLUSIONS Considering that ED results from a systemic arterial defect not only confined to the penile vasculature, implication of TNF-α in the pathophysiology of ED offers a humoral linking between CVD and ED.
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Claudino MA, da Silva FH, Mónica FZT, Rojas-Moscoso JA, De Nucci G, Antunes E. Long-term oral treatment with BAY 41-2272 ameliorates impaired corpus cavernosum relaxations in a nitric oxide-deficient rat model. BJU Int 2010; 108:116-22. [PMID: 20950311 DOI: 10.1111/j.1464-410x.2010.09776.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE • To investigate the potential beneficial effects of 4-week oral treatment with 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1Hpyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine (BAY 41-2272), a nitric oxide (NO)-independent soluble guanylate cyclase activator, on impaired rat corpus cavernosum relaxations in NO-deficient rats. MATERIAL AND METHODS • Male Wistar rats were divided into four groups: Control, N (G)-nitro-L- arginine methyl ester (L-NAME; 20 mg/rat/day), BAY 41-2272 (20 mg/kg/day) and L-NAME + BAY 41-2272. • Rats were treated with L-NAME concomitantly with BAY 41-2272 for 4 weeks. • Concentration-response curves to acetylcholine (ACh) and sodium nitroprusside (SNP), along with the nitrergic relaxations (1-32 Hz) were obtained in rat corpus cavernosum (RaCC). • The RaCC contractile responses to the α₁ -adrenoceptor agonist phenylephrine (PE) were obtained. RESULTS • Acetylcholine (0.01-1000 µmol/L) produced concentration-dependent relaxing responses in RaCC that were significantly enhanced (P < 0.05) in BAY 41-2272-treated rats. • The ACh-induced relaxations were largely reduced in L-NAME-treated rats, and co-treatment with BAY 41-2272 failed to significantly modify these impaired relaxations. • The SNP-induced relaxations were modified neither by L-NAME nor by co-treatment with BAY 41-2272. • The nitrergic relaxations were significantly amplified in BAY 41-2272-treated rats (at 16 and 32 Hz). A significant reduction in the nitrergic relaxations was observed in L-NAME-treated rats, an effect largely restored by co-treatment with BAY 41-2272. • The contractile RaCC responses produced by PE (0.001-100 µmol/L) were significantly higher (P < 0.05) in L-NAME-treated rats, and co-treatment of L-NAME with BAY 41-2272 nearly restored these enhanced contractile responses. CONCLUSION • Four-week therapy with BAY 41-2272 prevents the impaired corpus cavernosum relaxations of rats treated chronically with L-NAME, indicating that accumulation of cyclic guanosine monophosphate into erectile tissue counteracts the NO deficiency.
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Affiliation(s)
- Mário A Claudino
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas (Sao Paulo), Brazil
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Allahdadi KJ, Hannan JL, Tostes RC, Webb RC. Endothelin-1 induces contraction of female rat internal pudendal and clitoral arteries through ET(A) receptor and rho-kinase activation. J Sex Med 2010; 7:2096-2103. [PMID: 20412427 PMCID: PMC3061306 DOI: 10.1111/j.1743-6109.2010.01816.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION Endothelin-1 (ET-1), a potent vasoconstrictor peptide, acts mainly through the Gprotein-coupled ET(A) receptor (ET(A)R). Increased vascular ET-1 production and constrictor sensitivity have been observed in various cardiovascular diseases, including hypertension, as well as erectile dysfunction. The internal pudendal artery (IPA) supplies blood to the vagina and clitoris. Inadequate blood flow through the IPA may lead to insufficient vaginal engorgement and clitoral tumescence. AIM Characterize the effects of ET-1 on the IPA and clitoral artery (CA). METHODS IPA and CA from female Sprague Dawley rats (225-250 g) were mounted in myograph chambers. Arterial segments were submitted to increasing concentrations of ET-1 (10-10-10-6 M). Segments were incubated with the ET(A)R antagonist, atrasentan (10-8 M) or the Rho-kinase inhibitor, Y-27632 (10-6 M) 30 minutes prior to agonist exposure. All E(max) values are expressed as % KCl-induced maximal contraction. ET(A)R, RhoA, and Rho-kinase expression from IPA was evaluated by Western blot. mRNA of preproET-1, ET(A)R, ET(B)R, RhoA, and Rho-kinase were measured by real time PCR. MAIN OUTCOME MEASURES ET-1 constrictor sensitivity in IPA and CA, protein expression and messenger RNA levels of ET-1-mediated constriction components. RESULTS ET-1 concentration-dependently contracted IPA (% Contraction and pD2, respectively: 156 ± 18, 8.2 ± 0.1) and CA (163 ± 12, 8.8 ± 0.08), while ET(A)R antagonism reduced ET-1-mediated contraction (IPA: 104 ± 23, 6.4 ± 0.2; CA: 112 ± 17, 6.6 ± 0.08). Pretreatment with Y-27632 significantly shifted ET-1 pD2 in IPA (108 ± 24, 7.9 ± 0.1) and CA (147 ± 58 and 8.0 ± 0.25). Protein expression of ET(A)R, ET(B)R, RhoA, and Rho-kinase were detected in IPA. IPA and CA contained preproET-1, ET(A)R, ET(B)R, RhoA, and Rho-kinase message. CONCLUSION We observed that the IPA and CA are sensitive to ET-1, signaling through the ET(A)R and Rho-kinase pathway. These data indicate that ET-1 may play a role in vaginal and clitoral blood flow and may be important in pathologies where ET-1 levels are elevated.
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Affiliation(s)
| | | | - Rita C Tostes
- Medical College of Georgia-Physiology, Augusta, GA, USA; University of Sao Paulo-Pharmacology, Sao Paulo, Brazil
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Giachini FR, Sullivan JC, Lima VV, Carneiro FS, Fortes ZB, Pollock DM, Carvalho MHC, Webb RC, Tostes RC. Extracellular signal-regulated kinase 1/2 activation, via downregulation of mitogen-activated protein kinase phosphatase 1, mediates sex differences in desoxycorticosterone acetate-salt hypertension vascular reactivity. Hypertension 2009; 55:172-9. [PMID: 19901158 DOI: 10.1161/hypertensionaha.109.140459] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Extracellular signal-regulated kinase (ERK)1/2 has been reported to play a role in vascular dysfunction associated with mineralocorticoid hypertension. We hypothesized that, compared with female rats, an upregulation of ERK1/2 signaling in the vasculature of male rats contributes to augmented contractile responses in mineralocorticoid hypertension. Uninephrectomized male and female Sprague-Dawley rats received desoxycorticosterone acetate (DOCA) pellets (200 mg per animal) and saline to drink for 3 weeks. Control uninephrectomized rats received tap water to drink. Blood pressure, measured by telemetry, was significantly higher in male DOCA rats (191+/-3 mm Hg) compared with female DOCA rats (172+/-7 mm Hg; n=5). DOCA treatment resulted in augmented contractile responses to phenylephrine in aorta (22+/-3 mN; n=6) and small mesenteric arteries (13+/-2 mN; n=6) from male DOCA rats versus uninephrectomized male rats (16+/-3 and 10+/-2 mN, respectively; P<0.05) and female DOCA rats (15+/-1 and 11+/-1 mN, respectively). ERK1/2 inhibition with PD-98059 (10 micromol/L) abrogated increased contraction to phenylephrine in aorta (14+/-2 mN) and small mesenteric arteries (10+/-2 mN) from male DOCA rats, without any effects in arteries from male uninephrectomized or female animals. Compared with the other groups, phosphorylated ERK1/2 levels were increased in the aorta from male DOCA rats, whereas mitogen-activated protein kinase phosphatase 1 expression was decreased. Interleukin-10 plasma levels, which positively regulate mitogen-activated protein kinase phosphatase 1 activity, were reduced in male DOCA-salt rats. We speculate that augmented vascular reactivity in male hypertensive rats is mediated via activation of the ERK1/2 pathway. In addition, mitogen-activated protein kinase phosphatase 1 and interleukin 10 play regulatory roles in this process.
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Affiliation(s)
- Fernanda R Giachini
- Medical College of Georgia, Department of Physiology, 1120 Fifteenth St, CA-2095, Augusta, GA 30912-3000, USA.
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Linder AE, Dorrance AM, Mills TM, Webb RC, Leite R. Erectile function in two-kidney, one-clip hypertensive rats is maintained by a potential increase in nitric oxide production. J Sex Med 2009; 6 Suppl 3:279-85. [PMID: 19267850 DOI: 10.1111/j.1743-6109.2008.01185.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Hypertension is closely associated with erectile dysfunction (ED) as it has been observed in many experimental models of hypertension. Additionally, epidemiological studies show that approximately a third of hypertensive patients have ED. AIM To test the hypothesis that the two-kidney, one-clip (2K-1C) rat model of hypertension displays normal erectile function due to increased nitric oxide (NO) production in the penis. METHODS Ganglionic-induced increase in intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio was used as an index of erectile function in 2K-1C and in normotensive sham-operated (SHAM) anesthetized rats. Cavernosal strips from hypertensive and normotensive rats were used for isometric tension measurement. The contraction induced by alpha-adrenergic agonist phenylephrine and the relaxation induced by the NO donor sodium nitroprusside (SNP) and by the Rho-kinase inhibitor Y-27632 were performed in the absence and in the presence of the NO synthase inhibitor N(omega)-nitro-L-arginine (L-NNA). RESULTS Changes in ICP/MAP induced by ganglionic stimulation were not different between 2K-1C and SHAM rats. The contractile response induced by phenylephrine as well as the relaxation induced by SNP or the Y-27632 were similar in cavernosal strips from both groups. However, in the presence of L-NNA, the relaxation induced by Y-27632 was significantly impaired in 2K-1C compared to SHAM. CONCLUSIONS These data suggest that hypertension and ED could be dissociated from high levels of blood pressure in some animal models of hypertension. Erectile function in 2K-1C hypertensive rats is maintained in spite of the increased Rho-kinase activity by increased NO signaling.
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Affiliation(s)
- A Elizabeth Linder
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
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Carneiro FS, Zemse S, Giachini FRC, Carneiro ZN, Lima VV, Webb RC, Tostes RC. TNF-alpha infusion impairs corpora cavernosa reactivity. J Sex Med 2009; 6 Suppl 3:311-9. [PMID: 19267854 DOI: 10.1111/j.1743-6109.2008.01189.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Erectile dysfunction (ED), as well as cardiovascular diseases (CVDs), is associated with endothelial dysfunction and increased levels of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha). AIM We hypothesized that increased TNF-alpha levels impair cavernosal function. METHODS In vitro organ bath studies were used to measure cavernosal reactivity in mice infused with vehicle or TNF-alpha (220 ng/kg/min) for 14 days. Gene expression of nitric oxide synthase isoforms was evaluated by real-time polymerase chain reaction. MAIN OUTCOME MEASURES Corpora cavernosa from TNF-alpha-infused mice exhibited decreased nitric oxide (NO)-dependent relaxation, which was associated with decreased endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) cavernosal expression. RESULTS Cavernosal strips from the TNF-alpha-infused mice displayed decreased nonadrenergic-noncholinergic (NANC)-induced relaxation (59.4 +/- 6.2 vs. control: 76.2 +/- 4.7; 16 Hz) compared with the control animals. These responses were associated with decreased gene expression of eNOS and nNOS (P < 0.05). Sympathetic-mediated, as well as phenylephrine (PE)-induced, contractile responses (PE-induced contraction; 1.32 +/- 0.06 vs. control: 0.9 +/- 0.09, mN) were increased in cavernosal strips from TNF-alpha-infused mice. Additionally, infusion of TNF-alpha increased cavernosal responses to endothelin-1 and endothelin receptor A subtype (ET(A)) receptor expression (P < 0.05) and slightly decreased tumor necrosis factor-alpha receptor 1 (TNFR1) expression (P = 0.063). CONCLUSION Corpora cavernosa from TNF-alpha-infused mice display increased contractile responses and decreased NANC nerve-mediated relaxation associated with decreased eNOS and nNOS gene expression. These changes may trigger ED and indicate that TNF-alpha plays a detrimental role in erectile function. Blockade of TNF-alpha actions may represent an alternative therapeutic approach for ED, especially in pathologic conditions associated with increased levels of this cytokine.
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Affiliation(s)
- Fernando S Carneiro
- Institute of Biomedical Sciences, University of Sao Paulo, Pharmacology, Sao Paulo, SP, Brazil.
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