Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PENIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed2005

Estrogen-induced abnormal accumulation of fat cells in the rat penis and associated loss of fertility depends upon estrogen exposure during critical period of penile development.

We previously reported that diethylstilbestrol (DES) or estradiol valerate (EV) exposure at a dose of 0.10-0.12 mg/kg, or higher, per day, on alternate days, from postnatal days 2-12, resulted in abnormal penis development and infertility (H. O. Goyal et al., 2005, J. Androl. 26, 32-43). The objective of this study was to identify a critical developmental period(s) during which EV exposure results in the observed penile abnormalities. Male pups received EV at a dose of 0.10-0.12 mg/kg on postnatal day(s) 1, 1-3, 4-6, 1-6, 7-12, 13-18, 19-24, or 25-30. Fertility was tested at 102-115 days of age and tissues were examined at 117-137 days. Both penile morphology and fertility were unaltered in rats treated with EV after 12 days of age. Conversely, except in rats treated on postnatal day 1 only, none of the males treated prior to 12 days of age sired pups, and all had abnormal penises, including varying degrees of abnormal accumulation of fat cells and loss of cavernous spaces and smooth muscle cells in the corpora cavernosa penis, which were maximal in the 1-6-day group. Also, the preputial sheath was partially released or its release was delayed, and the weight of the bulbospongiosus muscle was significantly reduced. Plasma testosterone (T) in the 1-6- and 4-6-day groups and intratesticular T in the 4-6-day group were significantly lower. The testosterone surge, characteristic of controls in the first week of life, was suppressed in the 1-3-day group. Estrogen receptor alpha mRNA expression was enhanced in the body of the penis in the 1-3-day group, but not in the 13-18-day group. Hence, EV exposure prior to 12 days of age (as short as 1-3 days postnatal), but not after 12 days of age, results in long-term abnormal penile morphology, characterized by abnormal accumulation of fat cells in the corpora cavernosa penis and, consequently, loss of fertility.

Adipocytes↗
PubMed2003

Altered Sonic hedgehog signaling is associated with morphological abnormalities in the penis of the BB/WOR diabetic rat.

Erectile dysfunction (ED) is a common and debilitating pathological development that affects up to 75% of diabetic males. Neural stimulation is a crucial aspect of the normal erection process. Nerve injury causes ED and disrupts signaling of the Sonic hedgehog (Shh) cascade in the smooth muscle of the corpora cavernosa. Shh and targets of its signaling establish normal corpora cavernosal morphology during postnatal differentiation of the penis and regulate homeostasis in the adult. Interruption of the Shh cascade in the smooth muscle of the corpora cavernosa results in extensive changes in corpora cavernosal morphology that lead to ED. Our hypothesis is that the neuropathy observed in diabetics causes morphological changes in the corpora cavernosa of the penis that result in ED. Disruption of the Shh cascade may be involved in this process. We tested this hypothesis by examining morphological changes in the penis, altered gene and protein expression, apoptosis, and bromodeoxyuridine incorporation in the BB/WOR rat model of diabetes. Extensive smooth muscle and endothelial degradation was observed in the corpora cavernosa of diabetic penes. This degradation accompanied profound ED, significantly decreased Shh protein in the smooth muscle of the corpora cavernosa, and increased penile Shh RNA expression in the intact penis (nerves, corpora, and urethra). Localization and expression of Shh targets were also disrupted in the corpora cavernosa. Increasing our understanding of the molecular mechanisms that regulate Shh signaling may provide valuable insight into improving treatment options for diabetic impotence.

Animals↗
PubMed2004

Abnormal morphology of the penis in male rats exposed neonatally to diethylstilbestrol is associated with altered profile of estrogen receptor-alpha protein, but not of androgen receptor protein: a developmental and immunocytochemical study.

Objectives of the study were to determine developmental changes in morphology and expression of androgen receptor (AR) and estrogen receptor (ER)alpha in the body of the rat penis exposed neonatally to diethylstilbestrol (DES). Male pups received DES at a dose of 10 microg per rat on alternate days from Postnatal Day 2 to Postnatal Day 12. Controls received olive oil vehicle only. Tissue samples were collected on Days 18 (prepuberty), 41 (puberty), and 120 (adult) of age. DES-induced abnormalities were evident at 18 days of age and included smaller, lighter, and thinner penis, loss of cavernous spaces and associated smooth muscle cells, and increased deposition of fat cells in the corpora cavernosa penis. Fat cells virtually filled the entire area of the corpora cavernosa at puberty and adulthood. Plasma testosterone (T) was reduced to an undetectable level, while LH was unaltered in all treated groups. AR-positive cells were ubiquitous and their profile (incidence and staining intensity) did not differ between control and treated rats of the respective age groups. Conversely, ERalpha-positive cells were limited to the stroma of corpus spongiosus in all age groups of both control and treated rats, but the expression in treated rats at 18 days was up-regulated in stromal cells of corpora cavernosa, coincident with the presence of morphological abnormalities. Hence, this study reports for the first time DES-induced developmental, morphological abnormalities in the body of the penis and suggests that these abnormalities may have resulted from decreased T and/or overexpression of ERalpha.

Aging↗
PubMed2001

Aging-related expression of inducible nitric oxide synthase and markers of tissue damage in the rat penis.

Erectile dysfunction in the aging male results in part from the loss of compliance of the corpora cavernosal smooth muscle due to the progressive replacement of smooth muscle cells by collagen fibers. We have examined the hypothesis that a spontaneous local induction of inducible nitric oxide synthase (iNOS) expression and the subsequent peroxynitrite formation occurs in the penis during aging and that this process is accompanied by a stimulation of smooth muscle apoptosis and collagen deposition. The penile shaft and crura were excised from young (3-5 mo old) and old (24-30 mo old) rats, with or without perfusion with 4% formalin. Fresh tissue was used for iNOS and proteasome 2C mRNA determinations by reverse transcription polymerase chain reaction assay, ubiquitin mRNA by Northern blot, and iNOS protein by Western blot. Penile sections from perfused animals were embedded in paraffin and immunostained with antibodies against iNOS and nitrotyrosine, submitted to the TUNEL assay for apoptosis, or stained for collagen, followed by image analysis quantitation. A 4.1-fold increase in iNOS mRNA was observed in the old versus young tissues, paralleled by a 4.9-fold increase in iNOS protein. The proteolysis marker, ubiquitin, was increased 1.9-fold, whereas a related gene, proteasome 2c, was not significantly affected. iNOS immunostaining was increased 3.6-fold in the penile smooth muscle of the old rats as compared with the young rats. The peroxynitrite indicator nitrotyrosine was increased by 1.6-fold, accompanied by a 3.6-fold increase in apoptotic cells and a 2.0-fold increase in collagen fibers in the old penis. In conclusion, aging in the penis is accompanied by an induction of iNOS and peroxynitrite formation that may lead to the observed increase in apoptosis and proteolysis and may counteract a higher rate of collagen deposition in the old penis.

Aging↗
PubMed2000

Replantation of the penis: a patient report.

Replantation of the penis is an unusual case in this country and it is unlikely that most plastic and reconstructive surgeons or urologists will see one during their career. A successful repair of a self-inflicted amputation of the penis is presented. The unique anatomy of the penis pertinent to replantation is reviewed, and current concepts and recommendations in performing replantation of the penis are presented.

Adult↗
PubMedDate not supplied

Management of burns of the penis.

Burns of the penis can be physically and psychologically devastating. This is particularly true in young pediatric patients who have to content with growth as well as with the trials of adolescence and the development of self-image. Little has been written on the grafting management of these injuries. This report reviews a management technique used with great success. Ten patients who sustained full-thickness penis burns were reviewed. The grafting technique consisted of excision and grafting with sheet grafts in a one- or two-stage setting. After grafting, the penis was placed in traction with a weighted Foley catheter. Grafts were left open or stented. No complications occurred from the traction apparatus, and graft take was uniformly excellent. Short-term results have been excellent, and no urethral problems have developed over a median 3-year follow-up. This technique appears to provide excellent means of supporting the penis to accomplish superb graft take in this hard-to-manage area.

Burns↗
PubMed1999

Care of the degloved penis and scrotum: a 25-year experience.

Injuries to the penis and scrotum are both physically and mentally traumatic. If poorly managed in the acute setting, these injuries may become long-term problems or permanent disabilities. The purpose of this study was to review our approach to degloving injuries of the penis and scrotum and to present our experience. Over the past 25 years, we have cared for eight patients with complete degloving injuries of the genitalia. Farm equipment accidents were responsible for the majority of injuries. We attempted to close all wounds of the denuded penis and near-total avulsed scrotum at the initial operative intervention using the method of repair described. Postoperatively, all patients had an acceptable appearance and normal mictural and erectile function. We conclude that degloving injuries of the penis and scrotum can be best treated with this approach definitively in the acute setting with successful functional and aesthetic results.

Adult↗
PubMed2005

Keloid formation on an inconspicuous penis.

Inconspicuous penis is an umbrella term used to categorize several anatomic anomalies that occur in newborn boys. The consequences of this anomaly may be catastrophic unless it is accurately diagnosed. Repeated circumcisions will accentuate the problem without any solution. Keloid formation on the penis is exceptionally rare even though circumcision is a world-wide procedure. Herein, we present a 13-year-old boy with a buried glans penis, micturation difficulty, and keloid formation. He was previously circumcised twice before admission to our clinic. A surgical correction together with intralesional steroid injection was performed. The outcome of this procedure was satisfactory. We conclude that repeated circumcision may not be the best choice of treatment for keloid formation on the penis.

Adolescent↗
PubMed1992

The apical ligaments of the penis of the goat and sheep.

The penile apical ligaments of 13 goats and 8 sheep were dissected and described. Unlike the single apical ligament of the bull penis, both goats and sheep had one ligament on each side of the apex of the penis with no apparent connection over the dorsal surface. These lateral apical ligaments consisted of substantial connective tissue fibers that arose from the outer layers of the tunica albuginea and varied from 6.0 to 10.0 cm in length. The left apical ligament was longer and thicker than the right. The left apical ligament of the sheep penis was divided into a dorsal and a ventral branch. Both the goat and sheep possessed flattened perivenous ligaments that originated from the apical fascia and extended caudally along each side of the dorsal vein of the penis.

Animals↗
PubMed2005

Malassezia and Candida colonisation on glans penis of circumcised men.

The Malassezia yeast are members of the normal human cutaneous flora in adults. They also are reported as part of the microflora of the male genital region in mostly uncircumcised males. It has been reported that Malassezia sympodialis and Malassezia globosa are the most frequent yeast belonging to the resident microflora of the penis as in other human skin areas. The aim was to evaluate the prevalence of Malassezia and Candida yeast colonisation on the glans penis of circumcised males. Impression preparations were made on modified Dixon agar. The isolates were identified by morphological and physiological characteristics. A total of 245 circumcised males were included in the study. Of the 245 patients examined, 55 (22.4%) were found to have a mycologically proven yeast fungi on their glans penis. In 17 (30.9%) Malassezia, in 36 (65.5%) Candida, in one (1.8%) Malassezia and Candida, and in one (1.8%) Saccharomyces strains were detected. Malassezia furfur (66.7%) was the most common species among the lipophilic yeast, followed by Malassezia globosa (11.1%), Malassezia obtusa (11.1%) and Malassezia slooffiae (11.1%). Candida albicans was the most common non-lipophilic yeast (46.0%), that was isolated among the other yeast, followed by unidentified Candida strains (18.9%), Candida tropicalis (8.1%), Candida glabrata (8.1%), Candida parapsilosis (8.1%), Candida zeylanoides (5.4%), Candida guilliermondii (2.7%) and Saccharomyces cerevisiae (2.7%). The results of this study showed that Malassezia species were also colonised like Candida on the glans penis of circumcised males.

Adult↗
PubMed2005

Rupture of the superficial dorsal vein of the penis.

Unusual causes of acute penis, such as the rupture of a superficial vein of the penis, can mimic fractured penis. The diagnosis in such cases is mostly after exploration. The author describes a case where a high index of clinical suspicion led to the diagnosis of the rupture of a superficial dorsal vein of the penis without exploration. The patient had a successful recovery with conservative management.

Adult↗
PubMed1994

Adenylate and guanylate cyclase activity in the penis and aorta of the diabetic rat: an in vitro study.

OBJECTIVE: To investigate the role of adenylate and guanylate cyclases in the mediation of erection in diabetic rats. MATERIALS AND METHODS: Hyperglycaemic diabetes mellitus was induced in 35 rats using streptozotocin. Two months later the penises and aortae of these rats were excised and cut into rings or segments before being treated with varying concentrations of acetylcholine (Ach), sodium nitroprusside (NaNP), prostaglandin E1 (PGE1) and adrenaline (AD). The levels of adenosine 3'5'-cyclic monophosphate (cAMP) and guanosine 3'5'-cyclic monophosphate (cGMP) so generated were measured by radioimmunoassay and the results compared with those from seven age-matched control rats that had not been given streptozotocin. RESULTS: Ach-stimulated cGMP synthesis was impaired in the aortae in diabetic rats. Ach-stimulated cGMP synthesis was undetectable in the penis. NaNP-stimulated cGMP and PGE1-stimulated cAMP synthesis was enhanced in both the penises and aortae in diabetic rats compared with controls. AD-stimulated cAMP synthesis was enhanced in the aorta in diabetic rats compared with controls, but AD had no effect on cAMP synthesis in the penis. CONCLUSION: Ach-stimulated nitric oxide (NO) synthesis is impaired in the vasculature of diabetic rats and an Ach-NO axis may not be present in the penis of the rat. The enhanced capacity of the penis and vasculature to generate cAMP and cGMP may constitute an adaptive response to counteract the reduction in receptor-linked NO release. Impaired adenylate or guanylate cyclase activity does not contribute to erectile dysfunction in diabetic rats.

Adenylyl Cyclases↗
PubMed1985

The effect of hypoxia on neuroeffector transmission in the bovine retractor penis and rat anococcygeus muscles.

The effects of reducing the PO2 of the bathing fluid were studied on non-adrenergic non-cholinergic (NANC) transmission in isolated preparations of the bovine retractor penis muscle, the rat anococcygeus muscle, the guinea-pig taenia caeci and the guinea-pig urinary bladder. Hypoxia rapidly and reversibly impaired NANC transmission in the bovine retractor penis and rat anococcygeus muscles but did not affect transmission in the guinea-pig taenia caeci or bladder, suggesting that different NANC mechanisms are involved. Although neurally-evoked relaxation of the bovine retractor penis was impaired by hypoxia, relaxations produced by vasoactive intestinal peptide, prostaglandin E1, sodium nitroprusside or an inhibitory factor isolated from the bovine retractor penis were unaffected. Since the inhibitory factor is similar to, and may actually be the NANC transmitter, the results suggest that the site of action of hypoxia in impairing transmission is prejunctional at the inhibitory nerve endings.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed2006

Methylene blue-guided repair of fractured penis.

INTRODUCTION: Fracture of the penis is a condition where excessive force applied to the long axis of the penis in the erect state results in rupture of the tunica albuginea of the corpus cavernosum. Surgical management can be confusing and time-consuming due to the concealment of the tear in organized blood and edematous tissue, necessitating extensive dissection in friable traumatized tissues, especially if the tear is a small one, or if there are multiple tears. AIM: The present work investigates the value of methylene blue in aiding the localization of tunical and urethral tears in such cases. PATIENTS AND METHODS: Twelve cases with delayed presentation of fracture penis were managed. In six patients, methylene blue was injected into the corpora cavernosa and through the urethral meatus to point out tears. In the other six patients, methylene blue was not used. MAIN OUTCOME MEASURES: Operative time and complication rate. RESULTS: Operative time was considerably less in the group that received methylene blue, and the repair was more straightforward. Complications issued only in the group that did not receive methylene blue considering the extensive lengthy dissection. CONCLUSION: Methylene blue-guided repair for trauma of the penis is an easy, reliable, safe, and fast method for spotting tears in the tunica albuginea of the corpora cavernosa or in the urethra, eliminating the need for unnecessary lengthening.

Adult↗
PubMed2005

Age-related changes in phosphorylation of endothelial nitric oxide synthase in the rat penis.

AIM: Aging is associated with erectile dysfunction (ED) attributed to reduced nitric oxide synthase (NOS) activity and nitric oxide bioavailability. However, the mechanism for this effect has not been fully investigated. We evaluated (i) whether age-related ED involves dysregulation of endothelial NOS (eNOS) phosphorylation; and (ii) whether vascular endothelial growth factor (VEGF) exerts erectile effects and operates via eNOS phosphorylation in aged rats. METHODS: Male Fischer 344 "young" (4-month-old) and "aged" (19-month-old) rats were used. Electrical stimulation of the cavernous nerve (CNS) was performed to generate penile erection. Erectile response in the presence of rhVEGF165 was evaluated by intracavernosal pressure monitoring 25 minutes after intracavernosal injection of VEGF. Penes were excised at baseline, with or without rhVEGF treatment, and after CNS for Western immunoblot of phospho-eNOS (Ser-1177 and Thr-495), phospho-Akt, and eNOS. RESULTS: Erectile response was significantly reduced in aged rats compared with young rats. Phospho-eNOS (Ser-1177) and phospho-Akt were significantly reduced, while phospho-eNOS (Thr-495) was significantly increased, in the aged penis at baseline and after CNS. rhVEGF significantly improved erection and reversed downregulated Ser-1177, but not upregulated Thr-495 phosphorylation, on eNOS in aged penes. eNOS protein was significantly increased in aged penes. CONCLUSIONS: Age-related ED is associated with eNOS inactivation through a decrease in phosphorylation of its positive regulatory site (Ser-1177) and an increase in phosphorylation of its negative regulatory site (Thr-495) in the penis. Altered phosphorylation/constitutive activation of eNOS by fluid shear stress may be a major determinant of compromised vascular homeostasis of the aged penis. The finding that VEGF rapidly induces erection and partly corrects alterations in eNOS phosphorylation in the aged rat penis suggests impaired eNOS activation by deficient endogenous VEGF and supports the potential for growth factor therapy in the treatment of age-related ED.

Aging↗
PubMed2005

Mondor's disease of penis: a forgotten disease.

BACKGROUND: Mondor's disease of penis is an uncommon genital condition involving the penile sulcus in a circumferential manner. Although this disorder is almost always self limited, it is associated with considerable psychological stress and sexual disharmony. METHODS: All patients attending the sexually transmitted disease clinic during 1991-2003 were examined for evidence of Mondor's disease of penis. Detailed history and clinical findings were recorded in a specially designed proforma. Histopathological examination and staining with CD31 and CD34 monoclonal antibodies was also done in 11 patients. RESULTS: 18 out of 1296 patients attending the sexually transmitted diseases (STD) clinic during the study period were found to have penile Mondor's disease, giving an incidence of 1.39%. 17 patients had history of one or more episodes of STDs. Histopathological specimens showed prominent vessels with plump endothelial cells and thickened blood vessel walls. The occasional vessel showed complete occlusion of its lumen. CONCLUSIONS: In our study we did not find any evidence of lymphatic involvement. Non-lymphatic vessels, mainly veins, were predominantly involved. In our opinion Mondor's phlebitis of penis or Mondor's disease of penis are better terms to describe the condition rather than non-venereal sclerosing lymphangitis.

Adolescent↗
PubMed1990

Androgen receptor of rat penis is down-regulated by androgen.

To provide insight into the factors that control androgen receptor levels in rat penis, we assessed 5 alpha-[3H]-dihydrotestosterone binding in low-salt [10 mM tris(hydroxymethyl)aminomethane (Tris), 10 mM Na2M0O4] and high-salt (10 mM Tris, 10 mM Na2M0O4, 0.5 M KCl) extracts of rat penis using sucrose density gradients. Total receptor content decreased from approximately 729 +/- 114 fmol/g tissue at 3 wk of age to less than 50 fmol/g tissue at 10 wk of age. Castration of 3-wk-old rats prevented penile growth and the age-related decline in penile androgen receptor. Treatment of 3-wk-old castrated rats with 5 alpha-dihydrotestosterone caused an acceleration in the decline in receptor levels compared with intact animals. Castration of 10-wk-old rats (after androgen receptor levels had decreased) did not result in an increase in the amount of total androgen receptor by 16 wk of age. To determine the specificity of the androgen-mediated decline in receptor levels, the amounts of prostate androgen receptor were compared with those of the penis at different ages. When expressed as femtomoles per organ, the total androgen receptor level in the prostate increased fourfold from 3 to 10 wk of age, whereas the total androgen receptor in the penis declined approximately threefold. We conclude that the downregulation of the penile androgen receptor content that occurs in the rat between 3 and 10 wk of age is androgen mediated, does not occur in all androgen target tissues, and is prevented but not reversed by castration.

Aging↗
PubMed1983

Os penis of the rat. IV. The proximal growth cartilage.

Histomorphological and histochemical aspects of the proximal cartilage of os penis and its surrounding perichondrium in 60 rats aged between 1 and 100 days are described. Comparisons at 11-14 days with the mandibular condylar cartilage reveal a slight difference in their general morphological composition. The developmental changes which take place in the os penis cartilage reveal histomorphologic events, some of which may be brought into agreement with previous observations of patterns of transformations of the bone. Observations on an age-dependent morphological appearance of the area adjacent to the proximal surface of the cartilage suggest certain agreements between the mandibular angular cartilage and the os penis cartilage. The study of phosphomonoesterases in the os penis cartilage and its perichondrium reveals significant, unexplained differences in the distribution of alkaline phosphatase between this cartilage and the mandibular condylar cartilage.

Acid Phosphatase↗