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The Urologic Clinics of North America Nov 2005This article reviews the physiology of penile erection, the components of erectile function, and the pathophysiology of erectile dysfunction. The molecular and clinical... (Review)
Review
This article reviews the physiology of penile erection, the components of erectile function, and the pathophysiology of erectile dysfunction. The molecular and clinical under-standing of erectile function continues to gain ground at a particularly fast rate. Advances in gene discovery have aided greatly in working knowledge of smooth muscle relaxation/contraction pathways. The understanding of the nitric oxide pathway has aided not only in the molecular understanding of the tumescence but also greatly in the therapy of erectile dysfunction.
Topics: Erectile Dysfunction; Hemodynamics; Humans; Male; Muscle Contraction; Muscle, Smooth; Penile Erection; Penis
PubMed: 16291031
DOI: 10.1016/j.ucl.2005.08.007 -
Nature Communications Jul 2022The corpus cavernosum is the most important structure for penile erection, and its dysfunction causes many physiological and psychological problems. However, its...
The corpus cavernosum is the most important structure for penile erection, and its dysfunction causes many physiological and psychological problems. However, its cellular heterogeneity and signalling networks at the molecular level are poorly understood because of limited access to samples. Here, we profile 64,993 human cavernosal single-cell transcriptomes from three males with normal erection and five organic erectile dysfunction patients. Cell communication analysis reveals that cavernosal fibroblasts are central to the paracrine signalling network and regulate microenvironmental homeostasis. Combining with immunohistochemical staining, we reveal the cellular heterogeneity and describe a detailed spatial distribution map for each fibroblast, smooth muscle and endothelial subcluster in the corpus cavernosum. Furthermore, comparative analysis and related functional experiments identify candidate regulatory signalling pathways in the pathological process. Our study provides an insight into the human corpus cavernosum microenvironment and a reference for potential erectile dysfunction therapies.
Topics: Erectile Dysfunction; Humans; Male; Muscle, Smooth; Penile Erection; Penis; Transcriptome
PubMed: 35879305
DOI: 10.1038/s41467-022-31950-9 -
Andrologia Jul 2021The aim of the present study was to evaluate the size of the penis in flaccidity and in erection of Italian men. A total of 4,685 men living in Italy and who have been...
The aim of the present study was to evaluate the size of the penis in flaccidity and in erection of Italian men. A total of 4,685 men living in Italy and who have been visited at the Italian urology operating units were involved in the study between January 2019 and January 2020. Each patient was given details on how to measure their penis (erect length and circumference) in flaccidity and in erection, from the lower base to the distal penile tip. Mean (standard deviation [SD]) flaccid penis length was 9.47 (2.69), mean (SD) flaccid penis circumference was 9.59 (3.08), mean (SD) erect penis length was 16.78 (2.55) and mean (SD) erect penis circumference was 12.03 (3.82). At the linear regression analysis, height was associated with flaccid penis length (β = 0.04; p-value = .01), and erect penis length was (β = 0.05; p-value < .01) and erect penis circumference was (β = 0.06; p-value < .01). Height is proportional to the length of the penis in flaccidity and in erection, and to the circumference in erection. The increase in BMI leads to a reduction in the length of the erect penis, as well as weight gain reduces the length of the flaccid penis.
Topics: Humans; Italy; Male; Penile Erection; Penis; Regression Analysis
PubMed: 33748967
DOI: 10.1111/and.14053 -
Asian Journal of Andrology 2016Traditionally, testosterone and estrogen have been considered to be male and female sex hormones, respectively. However, estradiol, the predominant form of estrogen,... (Review)
Review
Traditionally, testosterone and estrogen have been considered to be male and female sex hormones, respectively. However, estradiol, the predominant form of estrogen, also plays a critical role in male sexual function. Estradiol in men is essential for modulating libido, erectile function, and spermatogenesis. Estrogen receptors, as well as aromatase, the enzyme that converts testosterone to estrogen, are abundant in brain, penis, and testis, organs important for sexual function. In the brain, estradiol synthesis is increased in areas related to sexual arousal. In addition, in the penis, estrogen receptors are found throughout the corpus cavernosum with high concentration around neurovascular bundles. Low testosterone and elevated estrogen increase the incidence of erectile dysfunction independently of one another. In the testes, spermatogenesis is modulated at every level by estrogen, starting with the hypothalamus-pituitary-gonadal axis, followed by the Leydig, Sertoli, and germ cells, and finishing with the ductal epithelium, epididymis, and mature sperm. Regulation of testicular cells by estradiol shows both an inhibitory and a stimulatory influence, indicating an intricate symphony of dose-dependent and temporally sensitive modulation. Our goal in this review is to elucidate the overall contribution of estradiol to male sexual function by looking at the hormone's effects on erectile function, spermatogenesis, and libido.
Topics: Aromatase; Estradiol; Germ Cells; Humans; Hypothalamo-Hypophyseal System; Leydig Cells; Libido; Male; Penile Erection; Sertoli Cells; Spermatogenesis; Testis; Testosterone
PubMed: 26908066
DOI: 10.4103/1008-682X.173932 -
Acta Poloniae Pharmaceutica 2011An aphrodisiac is a type of food or drink that has the effect of making those who eat or drink it more aroused in a sexual way. Aphrodisiacs can be categorized according... (Review)
Review
An aphrodisiac is a type of food or drink that has the effect of making those who eat or drink it more aroused in a sexual way. Aphrodisiacs can be categorized according to their mode of action into three groups: substances that increase libido (i.e., sexual desire, arousal), substances that increase sexual potency (i.e., effectiveness of erection) and substances that increase sexual pleasure. Some well-known aphrodisiacs are Tribulus terrestrins, Withania somnifera, Eurycoma longifolia, Avena sativa, Ginko biloba, and Psoralea coryifolia. Ethnobotanical surveys have indicated a large number of plants as aphrodisiacs. The paper reviews the recent scientific validation on traditionally used herbal plants as aphrodisiac herbs for the management of sexual disorder erectile dysfunction.
Topics: Aphrodisiacs; Arousal; Erectile Dysfunction; Humans; Male; Penile Erection; Phytotherapy; Plant Preparations; Sexual Behavior; Sexual Dysfunction, Physiological
PubMed: 21485695
DOI: No ID Found -
The Journal of Sexual Medicine Jun 2015Accurate data regarding the size of the erect penis are of great importance to several disciplines working with male patients, but little high-quality research exists on...
INTRODUCTION
Accurate data regarding the size of the erect penis are of great importance to several disciplines working with male patients, but little high-quality research exists on the subject, particularly in different ethnic groups and for erect penis size.
AIM
The aim of this study was to create a nomogram of erect penile dimensions in a large sample of Middle Eastern men.
METHODS
A retrospective cohort study of 778 men (mean age 43.7; range 20-82) attending urological outpatient clinics in Saudi Arabia was conducted. Exclusion criteria were age under 18 years, a presenting complaint of small or short penis, Peyronie's disease or complaint of congenital curvature, clinical hypogonadism, and previous penile surgery or trauma.
MAIN OUTCOME MEASURES
Three erect penile dimensions following induction of erection using intracavernosal injection of Quadrimix.
RESULTS
Mean patient body mass index (BMI) was 29.09 (standard deviation [SD] 5.76). The mean suprapubic skin-to-penile tip erect length was 12.53 cm (SD 1.93); the mean erect length from the symphysis pubis to the penile tip was 14.34 cm (SD 1.86); and the mean erect shaft circumference was 11.50 cm (SD 1.74). A nomogram was constructed and statistical analysis performed, demonstrating a weak negative correlation between BMI and erect penile length measured from the suprapubic skin (r = -0.283, P < 0.000) but not from bone to tip, and a weak negative correlation between age and both erect penile length measurements (skin to tip r = -0.177, P < 0.0005; bone to tip r = -0.099, P = 0.006).
CONCLUSION
A nomogram for Middle Eastern men can be used as a standard when advising men with small penis anxiety. The importance of measuring erect size and allowing for infra-pubic fat interference in measurement is emphasized. We envisage that this tool can be used to educate and reassure concerned men about the size of their penises.
Topics: Adult; Body Mass Index; Humans; Male; Middle Aged; Nomograms; Organ Size; Outcome Assessment, Health Care; Penile Erection; Penis; Pubic Bone; Retrospective Studies; Saudi Arabia
PubMed: 25904106
DOI: 10.1111/jsm.12894 -
Fertility and Sterility Jan 2020This literature review presents two unusual and mystifying disorders of penile erection: painful nocturnal erections, alternatively termed sleep-related painful...
This literature review presents two unusual and mystifying disorders of penile erection: painful nocturnal erections, alternatively termed sleep-related painful erections, and idiopathic stuttering priapism, a variant of recurrent ischemic priapism in which no cause is discernible. The disorders are closely related although they are distinct clinically and pathologically. The main subject areas of discussion are recognition, clinical evaluation and management although current concepts surrounding their causes and mechanisms are also addressed. It is acknowledged that despite the perceived rarities of these disorders they are impactful in terms of their disease profiles and consequences. Future advances in their management will require continued development of evidence-based treatments.
Topics: Humans; Male; Penile Erection; Priapism; REM Sleep Parasomnias; Rare Diseases
PubMed: 32033724
DOI: 10.1016/j.fertnstert.2019.11.013 -
Nature Communications Jun 2023Phosphodiesterase type 5 inhibitors (PDE5is) constitute the primary therapeutic option for treating erectile dysfunction (ED). Nevertheless, a substantial proportion of...
Phosphodiesterase type 5 inhibitors (PDE5is) constitute the primary therapeutic option for treating erectile dysfunction (ED). Nevertheless, a substantial proportion of patients, approximately 30%, do not respond to PDE5i treatment. Therefore, new treatment methods are needed. In this study, we identified a pathway that contributes to male erectile function. We show that mechano-regulated YAP/TAZ signaling in smooth muscle cells (SMCs) upregulates adrenomedullin transcription, which relaxed the SMCs to maintain erection. Using single-nucleus RNA sequencing, we investigated how penile erection stretches the SMCs, inducing YAP/TAZ activity. Subsequently, we demonstrate that YAP/TAZ plays a role in erectile function and penile rehabilitation, using genetic lesions and various animal models. This mechanism relies on direct transcriptional regulation of adrenomedullin by YAP/TAZ, which in turn modulates penile smooth muscle contraction. Importantly, conventional PDE5i, which targets NO-cGMP signaling, does not promote erectile function in YAP/TAZ-deficient ED model mice. In contrast, by activating the YAP/TAZ-adrenomedullin cascade, mechanostimulation improves erectile function in PDE5i nonrespondent ED model rats and mice. Furthermore, using clinical retrospective observational data, we found that mechanostimulation significantly promotes erectile function in patients irrespective of PDE5i use. Our studies lay the groundwork for exploring the mechano-YAP/TAZ-adrenomedullin axis as a potential target in the treatment of ED.
Topics: Animals; Humans; Male; Mice; Rats; Adrenomedullin; Erectile Dysfunction; Penile Erection; Penis; Retrospective Studies; YAP-Signaling Proteins; Transcriptional Coactivator with PDZ-Binding Motif Proteins
PubMed: 37353497
DOI: 10.1038/s41467-023-39009-z -
Sexual Medicine Reviews Oct 2021The most common cause of patient dissatisfaction after penile prosthesis placement is penile shortening compared with one's memory of a natural erection. Surgical... (Review)
Review
INTRODUCTION
The most common cause of patient dissatisfaction after penile prosthesis placement is penile shortening compared with one's memory of a natural erection. Surgical techniques as well as preoperative and postoperative protocols have been reported to preserve and possibly enhance penile length in someone undergoing penile prosthesis surgery.
OBJECTIVES
This article presents a description of as well as the authors' experience with presurgical protocols, intraoperative techniques, and postsurgical protocols that allow for preservation or enhancement of penile length for patients who undergo inflatable penile prosthesis insertion.
METHODS
An extensive, systematic literature review was performed using PubMed searching for key terms including penile lengthening, inflatablepenile prosthesis, penile girth, buried penis, and penile enhancement. All articles with subjective and/or objective penile length outcomes were reviewed.
RESULTS
Several preoperative treatment protocols were found for penile length preservation and enhancement, which included use of a vacuum erection device as well as traction therapy. Intraoperative techniques included cavernosal sparing, channeling without dilatation, circumferential penile degloving, ventral phalloplasty, suprapubic lipectomy, liposuction, suspensory ligament release, sliding technique, modified sliding technique, multislice technique, and aggressive implant sizing. Postoperative protocols included early device inflation and cycling. Table 1 summarizes and compares the various preoperative, intraoperative, and postoperative strategies identified during literature review with their corresponding reported length gain.
CONCLUSIONS
Many preoperative, intraoperative, and postoperative surgical techniques can be performed by high-volume implanters to improve one's perceived or true penile length. In the hands of experienced, high-volume implanters, these techniques can be very meaningful for patients undergoing penile prosthesis insertion, particularly those who are concerned with penile length. Shah B, Kent M, Valenzuela R. Advanced Penile Length Restoration Techniques to Optimize Penile Prosthesis Placement Outcomes. Sex Med Rev 2021;9:641-649.
Topics: Humans; Male; Penile Erection; Penile Implantation; Penile Prosthesis; Penis; Sex Reassignment Surgery
PubMed: 32653404
DOI: 10.1016/j.sxmr.2020.05.007 -
Revista Da Associacao Medica Brasileira... Sep 2020The vascular evaluation of the erectile function through Color Duplex-Doppler Ultrasound (CDDU) of the penis can benefit the therapeutic decision-making process.... (Review)
Review
INTRODUCTION
The vascular evaluation of the erectile function through Color Duplex-Doppler Ultrasound (CDDU) of the penis can benefit the therapeutic decision-making process. Unfortunately, there is no standard procedure for CDDU conduction, a fact that results in high result-interpretation variability.
OBJECTIVE
The aims of this review are to promote greater standardization during CDDU of the penis and discuss the fundamental principles for its accurate conduction.
METHODS
CDDU is initially conducted with the penis in the flaccid state; the whole penis must be assessed (images at B mode) with a high-frequency linear transducer (7.5-18 MHz). Intracavernous injection of vasodilating agents (prostaglandin E1, papaverine, phentolamine) is performed to induce a rigid erection. Serial measurements at different times should be taken during the CDDU session and penile rigidity must be assessed in each evaluation.
RESULTS
It is important to monitor the erection response after the vasoactive agent (hardness scale), and scanning during the best-quality erection should be contemplated. Manual self-stimulation, audiovisual sexual stimulation (AVSS), and vasoactive agent re-dosing protocols must be taken into account to reduce the influence of psychogenic factors and to help the patient to get the hardest erection possible. Such measurements contribute to the maximal relaxation of the erectile tissue, so the hemodynamic parameters are not underestimated.
CONCLUSIONS
CDDU is a relevant specialized tool to assess patients with erectile dysfunction; therefore, this guideline will help to standardize and establish uniformity in its conduction and interpretation, taking into consideration the complexity and heterogeneity of CDDU evaluations of the penis.
Topics: Erectile Dysfunction; Hemodynamics; Humans; Male; Penile Erection; Penis; Ultrasonography, Doppler, Color
PubMed: 33027442
DOI: 10.1590/1806-9282.66.9.1180