Abstract:
:Development and maintenance of penile erection requires the relaxation of the smooth muscle cells in the cavernous bodies and is essentially mediated by nitric oxide (NO). The penile flaccid state is conversely maintained by the alpha adrenergic neuroeffector system and by other vasoconstrictors, such as endothelin-1 (ET-1). In this study we examined the mechanisms involved in yohimbine-induced relaxation in human and rabbit corpora cavernosa (CC). We essentially found that yohimbine not only blocks contractions induced by adrenergic agonists, but also by non-adrenergic substances, such as ET-1. This effect was unrelated to antagonism at the level of ET receptors, because yohimbine did not affect ET-1-induced increase in intracellular calcium in isolated CC cells. Conversely, our data suggest that yohimbine counteracts ET-1-induced contractions by interfering with NO release from the endothelium. In fact, yohimbine-induced CC relaxation was inhibited by the mechanical removing of the endothelium and by blocking NO formation or signalling via guanylate cyclase and cGMP formation. Conversely, yohimbine activity was strongly increased by inhibiting cGMP degradation. In an experimental model of hypogonadism, performed on rabbits by chronic treatment with a long-lasting GnRH agonist, the relaxant yohimbine activity was also decreased, but completely restored by androgen supplementation. This effect was evident only in preparations in which the main source of NO was present (endothelium) or in which NO formation was not impaired by L-NAME. Our data indicate that the relaxant effect of yohimbine is both endothelium and androgen-dependent. This might justify the lack of efficacy of this drug in treatment of some form of organic erectile dysfunction.
journal_name
Int J Impot Resjournal_title
International journal of impotence researchauthors
Filippi S,Luconi M,Granchi S,Natali A,Tozzi P,Forti G,Ledda F,Maggi Mdoi
10.1038/sj.ijir.3900890subject
Has Abstractpub_date
2002-08-01 00:00:00pages
295-307issue
4eissn
0955-9930issn
1476-5489journal_volume
14pub_type
杂志文章abstract::Men with the metabolic syndrome demonstrate an increased prevalence of erectile dysfunction (ED). In the present study, we tested the effect of a Mediterranean-style diet on ED in men with the metabolic syndrome. Men were identified in our database of subjects participating in controlled trials evaluating the effect o...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901447
更新日期:2006-07-01 00:00:00
abstract::This prospective study determined the rate of abandonment of sildenafil therapy and assessed the reasons for abandonment. Between January 2001 and December 2002, 234 patients with erectile dysfunction (ED) at three independent centers successfully began therapy with sildenafil 50 or 100 mg. The rate of noncompliance w...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901252
更新日期:2005-01-01 00:00:00
abstract::Cross-linked dextran and polymethylmethacrylate mixture (Lipen-10) is newly developed tissue filler. The purpose of this study was to evaluate tolerability and efficacy of Lipen-10 on penile enhancement. Twenty adult males were included in this study. Lipen-10 was injected into the subcutaneous tissue of the penile sh...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2012.41
更新日期:2013-05-01 00:00:00
abstract::Early pharmacological prophylaxis has been reported to increase the return of spontaneous erections following radical prostatectomy (RP). In this study, we evaluated the role of intracavernosal alprostadil (PGE1) combined with sildenafil in stimulating early recovery of spontaneous erections following RP. In this pros...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901448
更新日期:2006-09-01 00:00:00
abstract::To date, the effects of long-term testosterone (T) administration on the human vagina are not completely understood. Thus, the aim of this study was to investigate the effects of long-term T treatment on vaginal tissue histology, estrogen receptor alpha (ERα) and beta (ERβ) expression and proliferation in female to ma...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2013.9
更新日期:2013-09-01 00:00:00
abstract::We evaluated the prevalence of erectile dysfunction (ED) in a cross-sectional community-based random sample of Egyptian men. ED was correlated with the socioeconomic status, risk factors and quality of life. Married men in Ismailia province were interviewed at home. Data were processed for 805 men with mean age of 43....
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901000
更新日期:2003-08-01 00:00:00
abstract::Nitric oxide (NO) is a physiologic signal essential to penile erection, and disorders that reduce NO synthesis or release in the erectile tissue are commonly associated with erectile dysfunction. NO synthase (NOS) catalyzes production of NO from L-arginine. While both constitutively expressed neuronal NOS (nNOS) and e...
journal_title:International journal of impotence research
pub_type: 杂志文章,评审
doi:10.1038/sj.ijir.3901209
更新日期:2004-06-01 00:00:00
abstract::Psoriasis is a chronic inflammatory skin disease and seems to be associated with erectile dysfunction (ED). ED is a predictor of future cardiovascular disease. It is important to identify ED early and investigate cardiovascular problems in psoriasis patients. The sample consisted of 191 psoriasis patients and 191 heal...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2016.6
更新日期:2016-05-01 00:00:00
abstract::Erectile dysfunction (ED) due to androgen deficiency is rare in the young population. We retrospectively evaluated in this study men aged 18-40 years presenting with ED from 2015 to 2017. The International Index of Erectile Function-5 (IIEF-5) and Erection Hardness Grade Scores (EHGS) were used to assess erectile func...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/s41443-018-0090-y
更新日期:2019-03-01 00:00:00
abstract::Penile erection is completely dependent on commands from the central nervous system. Spinal centers controlling penile erection are located in the thoracolumbar and lumbosacral spinal cord. These centers are activated by information from the periphery and supraspinal nuclei so as to elicit penile erection in a variety...
journal_title:International journal of impotence research
pub_type: 杂志文章,评审
doi:
更新日期:2000-03-01 00:00:00
abstract::In several studies we have recently demonstrated that orgasm induces prolactin secretion in healthy males and females. This suggests that prolactin may form a feedback regulator of the refractory period following orgasm. To examine this position we investigated the prolactin response of a healthy multi-orgasmic male s...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3900823
更新日期:2002-04-01 00:00:00
abstract::We have investigated the reliability of intracavernosal prostaglandin E1 (PGE1) office vs self-injection therapy in patients with erectile dysfunction (ED). A total of 298 male patients with ED were enrolled in this study. In all patients, intracavernosal titration of the PGE1 dose was performed. A total of 106 patien...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901388
更新日期:2006-03-01 00:00:00
abstract::In an observational study in men with erectile dysfunction (ED) consulting a general practitioner (GP) or urologist in Belgium, demographics, ED characteristics (including erection hardness score), co-morbidities and treatment expectations were evaluated using a structured questionnaire. In total, 341 GPs and 41 urolo...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2008.7
更新日期:2008-07-01 00:00:00
abstract::This paper: (i) describes the worldwide prevalence of erectile dysfunction (ED); (ii) presents age-specific incidence rates for ED in the US; (iii) summarizes some key epidemiologic correlates of ED in the general population; and (iv) considers the possibility that ED may be a biobehavioral marker (sentinel event) of ...
journal_title:International journal of impotence research
pub_type: 杂志文章,评审
doi:10.1038/sj.ijir.3900567
更新日期:2000-10-01 00:00:00
abstract::The objective of this study is to investigate whether the L-arginine/nitric oxide pathway is involved in the neurotransmission of paraventricular nucleus of hypothalamus (PVN) activation-induced penile erection in the rat. Male adult Sprague-Dawley rats anesthetized with pentobarbital were used. The femoral artery was...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3900825
更新日期:2002-06-01 00:00:00
abstract::Phosphodiesterase 5 (PDE5) inhibitors are efficacious in treating patients with erectile dysfunction. New PDE5 inhibitors with different selectivity and pharmacokinetic profiles have been vigorously pursued. Here we report two novel, potent, and selective PDE5 inhibitors, JNJ-10280205 and JNJ-10287069, with Ki values ...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901462
更新日期:2006-09-01 00:00:00
abstract::Only few studies have investigated the impact of surgery for rectal cancer on sexual function. Little of that research included quality of life (QoL) aspects and hardly any study analyzed the impact of age, gender and type of surgery on sexual function. The aim of the presented study was to address these issues. Over ...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901276
更新日期:2005-05-01 00:00:00
abstract::In a study on the diagnosis and treatment of erectile dysfunction (ED) in general practice, a self-selected sample of 90 general practitioners (GPs) (76 males, 14 females) from a predominantly urban population of 525 GPs were interviewed. It appeared that 59% would not actively interrogate a patient when an erection p...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:
更新日期:1994-06-01 00:00:00
abstract::Dissection of the pudendal nerve (PN) and its branches in 71 cadavers revealed anatomic variations not previously described. Knowledge of this variation is necessary to prevent nerve injury resulting in sexual of sensory dysfunction. Because descriptions vary, this study re-evaluated the anatomy of the PN as implicate...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2015.10
更新日期:2015-07-01 00:00:00
abstract::The frequency of sexual dysfunction (SD) is not very well known in patients with chronic hepatitis C. In this study, the prevalence of SD and its correlations with psychological and biological variables was assessed in 46 HCV positive patients. The mean age of patients was 46.4+/-9.4 y; the mean duration of HCV infect...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901267
更新日期:2005-03-01 00:00:00
abstract::The objective of this study was to investigate the predictive validity of the Dutch translation of the Golombok Rust Inventory of Sexual Satisfaction (GRISS) for the presence of clinically relevant sexual dysfunctions and patient's need of help. A total of 57 male urological outpatients (age 50.7+/-13.2 y; range 27-77...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3900966
更新日期:2003-04-01 00:00:00
abstract::Erectile dysfunction (ED) develops owing to psychogenic, organic or/and both of these two factors. The aim of this study was to investigate the relationship between penile cavernosal arterial flow and peripheral atherosclerosis in men with ED. This study was conducted on 102 patients who had presented to Radiology Cli...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2013.35
更新日期:2014-03-01 00:00:00
abstract::The effects of hypoxia (pO2: 50 mmHg), acidosis (pH: 6.9) or glucopenia (absence of glucose) in vitro on the tone of the rabbit corpus cavernosum were investigated. The recovery of smooth muscle contractility following exposure to these conditions was also assessed. Hypoxia, acidosis or glucopenia alone or in combinat...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901231
更新日期:2005-01-01 00:00:00
abstract:OBJECTIVES:Our objective was to elucidate the discussion points of circumcision on social media (SoMe) by looking at the Twitter activity. MATERIAL AND METHODS:Twitter searched for #circumcision hashtag via www.tweetarchivist.com , www.twitonomy.com , www.symplur.com . Total tweet numbers, most influencers, top users ...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/s41443-018-0058-y
更新日期:2018-10-01 00:00:00
abstract::Isometric tension measurement using a selective Rho-kinase inhibitor (+)- (R)-trans4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide (Y-27632) and a selective myosin light chain kinase (MLCK) inhibitor 1-(5-iodonaphthalene-1-sulfonyl)-1H-hexahydro-1,4-diazepine hydrochloride (ML7) were used in rabbit clitoral caver...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3900911
更新日期:2002-12-01 00:00:00
abstract::The objective of this study was to evaluate the effect on erections of impeding venous blood flow following intracavernosal injections of prostaglandin E1. Dispersion of injected X-ray contrast medium indicated that application of the RMRI penile clamp to the base of the penis retarded venous outflow. The clamp was th...
journal_title:International journal of impotence research
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:1995-03-01 00:00:00
abstract::Chronic hypoxia is related to many pathological conditions: aging, heart and respiratory failure, sleep apneas, smoke, chronic obstructive pulmonary disease (COPD), diabetes, hypertension and arteriosclerosis, all characterized by reductions of sleep-related erections (SREs) and by erectile dysfunction (ED). Sleep-rel...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901560
更新日期:2007-09-01 00:00:00
abstract::The aims of this study were to investigate the prevalence of ED in Chinese men with type 2 diabetes mellitus, and evaluate the efficacy and safety of sildenafil citrate in these patients. Patients from 42 outpatient diabetes clinics with type 2 diabetes mellitus and ED as defined by the International Index of Erectile...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/ijir.2010.21
更新日期:2010-09-01 00:00:00
abstract::In a prospective, placebo-controlled, one group crossover design study, we tested whether adding programmed intracavernous PGE1 injections (IC-PGE1) can improve the effectiveness of sildenafil in erectile dysfunction (ED) patients unresponsive to monotherapy with this drug. In all, 40 ED patients who had experienced u...
journal_title:International journal of impotence research
pub_type: 临床试验,杂志文章
doi:10.1038/sj.ijir.3901290
更新日期:2005-07-01 00:00:00
abstract::The first goal of this study was to examine the effect of secondhand smoking on neurogenic, endothelium- and cGMP-dependent relaxant responses of rabbit corpus cavernosum smooth muscle. Our second goal was to determine whether such an effect can be prevented by oral administration of L-arginine. Male New Zealand rabbi...
journal_title:International journal of impotence research
pub_type: 杂志文章
doi:10.1038/sj.ijir.3901341
更新日期:2005-09-01 00:00:00