Experimental priapism is associated with increased oxidative stress and activation of protein degradation pathways in corporal tissue.

Priapism is a debilitating disease for which there is at present no clinically accepted pharmacological intervention. It has been estimated that priapism lasting more than 24 h in patients is associated with a 44-90% rate of ED. In this investigation, we determined in two animal models of priapism (opiorphin-induced priapism in the rat and priapism in a mouse model of sickle cell disease) if there is evidence for an increase in markers of oxidative stress in corporal tissue. In both animal models, we demonstrate that priapism results in increased levels of lipid peroxidation, glutathione S-transferase activity and oxidatively damaged proteins in corporal tissue. Using western blot analysis, we demonstrated there is upregulation of the ubiquitination ligase proteins, Nedd-4 and Mdm-2, and the lysosomal autophage protein, LC3. The antiapoptotic protein, Bcl-2, was also upregulated. Overall, we demonstrate that priapism is associated with increased oxidative stress in corporal tissue and the activation of protein degradation pathways. As oxidative stress is known to mediate the development of ED resulting from several etiologies (for example, ED resulting from diabetes and aging), we suggest that damage to erectile tissue resulting from priapism might be prevented by treatments targeting oxidative stress.

Expression of myosin isoforms in the smooth muscle of human corpus cavernosum.

The molecular interaction between smooth muscle (SM) myosin and actin in the corpus cavernosum (CC) determines the erectile state of the penis. A key mechanism regulating this interaction and subsequent development and maintenance of force is alternative splicing of SM myosin heavy chain (MHC) and 17 kDa essential SM myosin light chain (MLC) pre-mRNAs. Our aim was to examine the relative SM myosin isoform composition in human CC. Tissue samples were obtained from 18 patients with erectile dysfunction (ED), Peyronie's disease, or both. One specimen was obtained during a transgender operation. Patients then were stratified according to presence of diabetes mellitus, hypertension, ED, or Peyronie's disease, as well as failure of phosphodiesterase-5 (PDE5) inhibitors and history of previous pelvic or penile surgeries, radiation, or both. Our results revealed that all human CC samples expressed only the SM-A isoform. There was a predominance of SM2 isoform mRNA relative to SM1 across all samples, with a mean of 63.8%, which correlated with protein analysis by gel electrophoresis. A statistically significant difference was found between patients who had undergone previous pelvic surgery, radiation, or both and those who did not. The ratio of LC(17b) to LC(17a) was approximately 1:1 for all patients, with a mean of 48.9% LC(17b). Statistical difference was seen in the relative ratio of LC(17b) to LC(17a) among the group who failed conservative therapy with PDE5 inhibitors compared with all others. In conclusion, we determined the SM myosin isoform composition of human CC and present for the first time differences in relative myosin isoform expression among patients with several risk factors contributing to their cause of ED. Our data reflect the fact that alternative splicing events in the MHC and 17 kDa MLC pre-mRNA may be a possible molecular mechanism involved in the altered contractility of the CCSM in patients with ED.

Polymorphism of the insulin gene is associated with increased prostate cancer risk.

High insulin levels are linked with increased cancer risk, including prostate cancer. We examined the associations between prostate cancer with polymorphisms of the insulin gene (INS) and its neighbouring genes, tyrosine-hydroxylase and IGF-II (TH and IGF2). In this study, 126 case-control pairs matched on age, race, and countries of origin were genotyped for +1127 INS-PstI in INS, -4217 TH-PstI in TH, and +3580 IGF2-MspI in IGF2. The homozygous CC genotype of +1127 INS-PstI occurred in over 60% of the population. It was associated with an increased risk of prostate cancer in nondiabetic Blacks and Caucasians (OR=3.14, P=0.008). The CC genotype was also associated with a low Gleason score <7 (OR=2.60, P=0.022) and a late age of diagnosis (OR=2.10, P=0.046). Markers in the neighbouring genes of INS showed only null to modest associations with prostate cancer. The polymorphism of INS may play a role in the aetiology of prostate cancer. Given the high prevalence of the CC genotype and its association with late age of onset of low-grade tumours, this polymorphism may contribute to the unique characteristics of prostate cancer, namely a high prevalence of indolent cancers and the dramatic increase in incidence with age.

Hypervascularity of the glans penis diagnosed with cutaneous temperature measurements.

Hypervascularity of the penis is a complication that has been described after deep dorsal vein arterialization. We present a patient with hypervascularity of the penis which was diagnosed with cutaneous temperature measurements of the penis. Our patient underwent both pre- and post-operative cutaneous temperature measurements taken at seven locations along the shaft and glans of the penis with the Physitemp BTE-2A Thermal Sensitivity Tester. After deep dorsal vein arterialization our patient's cutaneous temperature at the glans increased 4.2 degrees C. After ligation of the distal deep dorsal vein for hypervascularity, the cutaneous temperature at the glans decreased 1.3 degrees C. We present a novel technique using cutaneous tempewrature measurements which may be used as a test for the efficacy of arterial revascularization and its potential complications.

Potassium channels and human corporeal smooth muscle cell tone: diabetes and relaxation of human corpus cavernosum smooth muscle by adenosine triphosphate sensitive potassium channel openers.

PURPOSE: Sustained contraction of human corporeal smooth muscle depends on continuous transmembrane calcium flux through voltage gated calcium channels. K channels modulate corporeal smooth muscle membrane potential and, thus, ultimately affect transmembrane calcium flux. Therefore, we characterized relaxation responses elicited by the K channel modulators pinacidil and levcromakalim on isolated human corporeal tissue strips. We also evaluated the possibility that there may be alterations in adenosine triphosphate sensitive K channel pharmacology/function related to the presence of diabetes mellitus. MATERIALS AND METHODS: A total of 215 isolated human corporeal tissue strips obtained from 57 male patients with organic erectile dysfunction were investigated. Cumulative concentration-response curves were constructed at half log increments for steady state relaxation responses elicited by pinacidil and levcromakalim on equivalently phenylephrine pre-contracted (to approximately 75% of maximum) isolated corporeal tissue strips. Potassium currents were measured using the cell attached whole cell patch clamp technique on freshly isolated corporeal smooth muscle cells. RESULTS: A concentration dependent, glibenclamide sensitive relaxation response of phenylephrine pre-contracted corporeal tissue strips was observed for pinacidil and levcromakalim. Consistent with such observations, electrophysiological recordings on freshly isolated myocytes revealed that pinacidil (10 microM.) and levcromakalim (10 microM.) induced whole cell potassium currents that were blocked by glibenclamide (10 microM.). In addition, statistical analysis revealed that phenylephrine pre-contracted corporeal tissue strips from patients without diabetes were more sensitive to relaxation by both compounds than corporeal tissue strips excised from those with diabetes. Furthermore, relaxation responses elicited by pinacidil and levcromakalim were not affected by charybdotoxin or 4-aminopyridine but were completely reversed by KCl or tetraethylammonium chloride. CONCLUSIONS: These data indicate that the adenosine triphosphate sensitive K channel subtype is likely to have an important role in the relaxation of isolated corporeal tissue strips and, moreover, they are the molecular target for the K channel modulators/openers levcromakalim and pinacidil. Such observations are consistent with the supposition that alterations in the structure/function/activity of these potassium channels may underlie at least some aspects of observed diabetes related differences in tissue sensitivity to K channel modulators.

Bladder injection of "naked" hSlo/pcDNA3 ameliorates detrusor hyperactivity in obstructed rats in vivo.

The goal of these studies was to examine the potential utility of bladder instilled K+ channel gene therapy with hSlo cDNA (i.e., the maxi-K channel) to ameliorate bladder overactivity in a rat model of partial urinary outlet obstruction. Twenty-two female Sprague-Dawley rats were subjected to partial urethral (i.e., outlet) obstruction, with 17 sham-operated control rats run in parallel. After 6 wk of obstruction, suprapubic catheters were surgically placed in the dome of the bladder in all rats. Twelve obstructed rats received bladder instillation of 100 microg of hSlo/pcDNA in 1 ml PBS during catheterization, and another 10 obstructed rats received 1 ml PBS (7 rats) or 1 ml PBS containing pcDNA only (3 rats). Two days after surgery cystometry was performed on all animals to examine the characteristics of the micturition reflex in conscious and unrestrained rats. Obstruction was associated with a three- to fourfold increase in bladder weight and alterations in virtually every micturition parameter estimate. PBS-injected obstructed rats routinely displayed spontaneous bladder contractions between micturitions. In contrast, hSlo injection eliminated the obstruction-associated bladder hyperactivity, without detectably affecting any other cystometric parameter. Presumably, expression of hSlo in rat bladder functionally antagonizes the increased contractility normally observed in obstructed animals and thereby ameliorates bladder overactivity. These initial observations indicate a potential utility of gene therapy for urinary incontinence.

The genetics and immunology of Peyronie's disease.

Peyronie's disease (PD) is a condition characterized by localized and often progressive fibrosis and scarring of the penis. This condition has an unknown etiology although several hypotheses have been proposed. These include traumatic, immunologic and genetic causes. We studied the genetics and immunology of PD using both molecular biologic and molecular genetic techniques. Men (n=283) with PD were identified by retrospective chart review of one physician's office practice. These men were contacted by telephone and asked to submit to an interview and blood test for genetic studies. Simultaneously, tissue and cells collected in the laboratory were examined by Western and Northern blot analysis for examination of protein and RNA for expression of HLA. Of the first 107 men contacted, 24 were available and consented to interview and blood testing. The mean age was 60.3 y with an average duration of PD of 4.9 y. One patient had a family history of PD while no patients had Dupuytren's contracture. Twenty patients were considered to have primary disease while four were secondary. Eleven patients had tissue prepared for Northern blot analysis and nine patients were the subject of Western blot analysis. All tissue, both Peyronie's and control expressed class I MHC while no tissue expressed class II MHC. The expression of mRNA of class I MHC was equal for Peyronie's and control patients while the expression at the protein level was less in the PD patients. We conclude that PD may have multiple etiologic agents. One cannot exclude a class II MHC association but in our population, HLA DQ is not expressed. Class I MHC may be involved as the expression of class I MHC protein is different in Peyronie's patients than in controls. Genetic studies are ongoing. International Journal of Impotence Research (2000) 12, Suppl 4, S127-S132.

Premature ejaculation, priapism, and Peyronie's disease.

Male sexual dysfunction takes many forms. Sexual disorders include common conditions that patients may regard as simply a minor inconvenience, such as premature ejaculation; less common but medically serious disorders, such as lowflow priapism; and uncommon conditions, such as Peyronie's disease. These conditions may appear in conjunction with more generalized erectile dysfunction, or they may appear in isolation. Discerning the precise nature of the disorder is a crucial aspect of determining the best course of treatment.

Serum prostate-specific antigen and prostate volume predict long-term changes in symptoms and flow rate: results of a four-year, randomized trial comparing finasteride versus placebo. PLESS Study Group.

OBJECTIVES: To determine whether baseline prostate-specific antigen (PSA), in addition to prostate volume, is associated with long-term changes in symptoms and urinary flow rate. METHODS: Three thousand forty men with benign prostatic hyperplasia enrolled in the PLESS trial were randomly assigned to finasteride 5 mg or placebo for 4 years. Symptoms and flow rate were assessed every 4 months, and data were analyzed by dividing the patients into three groups by baseline PSA tertiles (0 to 1.3, 1.4 to 3.2, and 3.3 ng/mL or greater) and baseline prostate volume tertiles (14 to 41, 42 to 57, and 58 to 1 50 mL). RESULTS: After the initial placebo effect, a slow deterioration in symptoms over time was observed in the placebo-treated men with a baseline PSA 1.4 ng/mL or greater. However, placebo-treated men in the lowest PSA tertile (less than 1.4 ng/mL) had sustained symptomatic improvement that was not seen in placebo-treated men in the higher tertiles (P<0.001). In all finasteride-treated groups, there was initial improvement followed by maintenance or continued symptom improvement over time (approximately 3 to 3.5 points by the end of 4 years). The differences in symptom score improvement between placebo and finasteride were marginal for men with baseline PSA levels less than 1.4 ng/mL (P = 0.128) but were highly significant for men with PSA levels 1.4 ng/mL or greater (P<0.001). Urinary flow rate results were similar to those observed for symptoms. Analysis of symptom and flow rate data by prostate volume tertiles in a 10% subset of men yielded similar results, namely a deterioration of symptoms and flow rate in the two higher tertiles treated with placebo (greater than 41 mL) and a sustained improvement in all three groups of finasteride-treated patients. CONCLUSIONS: Baseline PSA and prostate volume are good predictors of long-term symptomatic and flow rate changes. Baseline PSA levels of 1.4 ng/mL or greater and enlarged prostate glands predict the best long-term response to finasteride compared with placebo.

The reported sex and surgery satisfactions of 28 postoperative male-to-female transsexual patients.

From 1980 to July 1997 sixty-one male-to-female gender transformation surgeries were performed at our university center by one author (A.M.). Data were collected from patients who had surgery up to 1994 (n = 47) to obtain a minimum follow-up of 3 years; 28 patients were contacted. A mail questionnaire was supplemented by personal interviews with 11 patients and telephone interviews with remaining patients to obtain and clarify additional information. Physical and functional results of surgery were judged to be good, with few patients requiring additional corrective surgery. General satisfaction was expressed over the quality of cosmetic (normal appearing genitalia) and functional (ability to perceive orgasm) results. Follow-up showed satisfied who believed they had normal appearing genitalia and the ability to experience orgasm. Most patients were able to return to their jobs and live a more satisfactory social and personal life. One significant outcome was the importance of proper preparation of patients for surgery and especially the need for additional postoperative psychotherapy. None of the patients regretted having had surgery. However, some were, to a degree, disappointed because of difficulties experienced postoperatively in adjusting satisfactorily as women both in their relationships with men and in living their lives generally as women. Findings of this study make a strong case for making a change in the Harry Benjamin Standards of Care to include a period of postoperative psychotherapy.

The epidemiology and pathophysiology of erectile dysfunction.

PURPOSE: Published studies on the epidemiology of erectile dysfunction and the physiology/ pathophysiology of erectile function are reviewed. MATERIALS AND METHODS: A literature search of more than 400 studies of the epidemiology and pathophysiology of impotence and erectile dysfunction published during the last 3 decades was conducted and the most pertinent articles are discussed. RESULTS: It has been estimated that the prevalence of erectile dysfunction of all degrees is 52% in men 40 to 70 years old, with higher rates in those older than 70 years. Erectile dysfunction has a significant negative impact on quality of life. Risk factors for erectile dysfunction include aging, chronic illnesses, various medications and cigarette smoking. A nitric oxide/cyclic guanosine monophosphate mechanism has an important role in mediating the corporal smooth muscle relaxation necessary for erectile function. Other mechanisms involving neuropeptides, gap junctions and ion channels also may modulate corporal smooth muscle tone. Erectile dysfunction can be due to vasculogenic, neurogenic, hormonal and/or psychogenic factors as well as alterations in the nitric oxide/cyclic guanosine monophosphate pathway or other regulatory mechanisms, resulting in an imbalance in corporal smooth muscle contraction and relaxation. CONCLUSIONS: Erectile dysfunction is a common condition associated with aging, chronic illnesses and various modifiable risk factors. Normal penile erection is a hemodynamic process that is dependent on corporal smooth muscle relaxation mediated by parasympathetic neurotransmission, nitric oxide, and possibly other regulatory factors and electrophysiological events. As more knowledge is gained of the physiology and regulatory factors that mediate normal erectile function, the mechanisms involved in the pathophysiology of erectile dysfunction should be further elucidated.

Formation of neoclitoris from glans penis by reduction glansplasty with preservation of neurovascular bundle in male-to-female gender surgery: functional and cosmetic outcome.

PURPOSE: During male-to-female gender reassignment surgery we used an abdominal pedicled inverted penile skin technique to create a vagina and extra folds of skin to create a clitoral hood. Although patients had orgasms with that technique, there was a general request for the placement of a sensate, erectile clitoris. Therefore, in 10 such patients undergoing transsexual surgery a neoclitoris was fashioned from the glans penis. Surgical technique and results are described. MATERIAL AND METHODS: From 1980 to 1995, 57 male-to-female gender surgeries were performed at our university center. In the last 10 such patients undergoing transsexual surgery a neoclitoris was created. Glans volume is reduced to match that of a normal size clitoris and the entire length of the dorsal neurovascular bundle is preserved. The neoclitoris is placed through a buttonhole in the newly constructed introitus. There was minimal bleeding from the bundle intraoperatively. RESULTS: In 8 of 10 patients the neoclitoris remained intact postoperatively with good sensation to touch, vibration and light pressure (sexual sensation). The cosmetic and functional appearance was that of a normal clitoris, and patients were satisfied. In 2 patients the results were not satisfactory because of necrosis of the neoclitoris. CONCLUSIONS: This technique has excellent functional and cosmetic results in the majority of patients. Preservation of the somatic, tactile and vibratory sensation of the neoclitoris is surgically practical, and can afford the patient the possibility of a more functional outcome of gender reassignment surgery.

Pelvic arteriovenous malformation mimicking seminal vesicle cyst.

Congenital pelvic arteriovenous malformations are rare entities, especially in males. Presenting symptoms, if any at all, are commonly a mass, thrill, bruit, or pain. Treatment options include surgical extirpation, embolization, or a combination of both. This case provides support for the last option in a patient presenting with symptoms localized to the seminal vesicles.

Use of intralesional verapamil to dissolve Peyronie's disease plaque: a long-term single-blind study.

OBJECTIVES: Multiple conservative therapies for the treatment of Peyronie's disease have been offered with variable and poor response rates. Calcium channel blockers have been shown in vitro and in vivo to inhibit secretion and synthesis of extracellular matrix, including collagen, glycosaminoglycans, and fibronectin, as well as causing increased collagenase and anti transforming growth factor-beta activity. Calcium antagonists, including verapamil, are effective in stimulating the remodeling and degradation of extracellular matrix in tissue by altering the metabolic pathways of fibroblasts. Recently, a pilot study (1994) showed preliminary promising results in treating plaque caused by Peyronie's disease. This randomized single-blind placebo-based study (1994 to 1996) was undertaken to confirm the hypothesis. METHODS: In this randomized single-blind study, 14 patients completed the study and were divided into two groups: the verapamil treatment group (n = 7) or the control saline group (n = 7). Verapamil or saline was injected directly into the Peyronie's plaque once a week for 6 months. Patients were evaluated before and after treatment with duplex ultrasound to confirm the extent of the lesion and to measure volume of the plaque, and by interview and mailed questionnaire 3 months after treatment. Patients being treated with oral calcium antagonists were excluded from the study. RESULTS: A decreased plaque volume was measured in 57% of the verapamil-treated men versus 28% in the control group (P <0.04). Penile curvature demonstrated an improvement trend of 37.71 +/- 9.3 degrees to 29.57 +/- 7.3 degrees in the verapamil-treated patients, but the difference was not significant (P <0.07). Plaque softening was noted in all patients treated with verapamil. There was significant objective improvement in plaque-associated penile narrowing in all patients in the verapamil group. Subjective plaque-associated erectile dysfunction (quality of erection) showed improvement in 42.87% of the verapamil group versus none in the control group (P <0.02). There was no local or systemic toxicity except for an occasional ecchymosis/bruise at the injection site. After a positive clinical response, plaque size, penile angulation, and symptoms continued to improve. Decrease in plaque size was noted in each of the responders in the first 3 months. CONCLUSIONS: This randomized single-blind study suggests that intralesional injection of calcium channel blocker may be a reasonable approach in some selected patients for the treatment of Peyronie's disease with noncalcified plaque and penile angulation of less than 30 degrees. Patients whose plaque failed to respond to intralesional verapamil therapy within 3 months or whose angulation was greater than 30 degrees at presentation were more likely to benefit from surgery.

Results of surgical treatment for abnormal penile curvature: Peyronie's disease and congenital deviation by modified Nesbit plication (tunical shaving and plication).

PURPOSE: We report a modification of the Nesbit plication with partial thickness shaving instead of conventional excision of a wedge of tunica albuginea. The technique minimizes intraoperative bleeding, obviates cavernous tissue damage and improves adhesion of plicated tunical layers. MATERIALS AND METHODS: Between September 1988 and September 1994, 32 patients underwent modified plication repair of chordee secondary to Peyronie's disease (26) or congenital penile deviation (6). The results were evaluated in the spring of 1996. RESULTS: Mean age plus or minus standard deviation was 55 +/- 8.8 years for patients with Peyronie's disease and 27 +/- 6.85 years for those with congenital penile deviation. Mean duration of Peyronie's disease was 22 +/- 9 months. Eight patients complained of erectile dysfunction and penile curvature. Plication for congenital deviation (6 patients) resulted in 100% satisfaction with the surgical result. Of the 26 men with Peyronie's disease 19 (78%) reported a good to excellent outcome. With prolonged followup (1 to 5 years) 7 patients had recurrent curvature due to progression of disease, including 5 with mild curvature who were able to have intercourse, in contrast with 2 who had severe early recurrence of deformity (more than 30 degrees) within 1 year postoperatively and underwent a second modified plication with good clinical outcome. Six of 32 patients with peyronie's disease were unable to resume satisfactory coitus with a postoperative straight penis. All 6 patients had concomitant poor erections preoperatively as shown by nocturnal peniletumescence and rigidity testing and 5 of them resumed regular intercourse with intracavernous pharmacotherapy. CONCLUSIONS: Long-term results of this modified plication demonstrate excellent clinical outcome with minimal morbidity.

Reduced connexin 43 expression in high grade, human prostatic adenocarcinoma cells.

Gap junction-mediated communication is required for normal cellular growth and differentiation. As cancer is thought to be a manifestation of the breakdown of cell-cell communication, with the concomitant loss of growth control, it would be expected that alterations in the primary structure, processing, oligomerization or trafficking of connexin (cxn) molecules would have a profound effect on the neoplastic process. Here we a present a preliminary immunohistochemical and molecular analysis of cxn 43 expression in prostatic epithelial cells from resected human tissue. Our data indicate that benign prostatic epithelial cells express cxn 43 protein, but that this expression is diminished in more advanced, anaplastic cancer cells. These data suggest that decreased connexin expression is not involved in the initiation of prostate cancer, but rather occurs during the progression of the disease.

Forskolin: a promising new adjunct to intracavernous pharmacotherapy.

PURPOSE: To evaluate the utility of forskolin as a potentially novel intracavernous therapy. MATERIALS AND METHODS: Forskolin- and prostaglandin E1 (PGE1)-induced intracorporal pressure changes were evaluated in vivo by cavernosometry performed on 2 male mongrel dogs, while systemic pressure changes were simultaneously monitored. Forskolin- and PGE1-induced intracellular cAMP accumulation was measured in vitro on homogeneous explant cultures of canine corporal smooth muscle cells. RESULTS: Forskolin and PGE1 elicited concentration-dependent increases in cAMP accumulation in cultured canine corporal smooth muscle cells. Forskolin and PGE1 also elicited concentration-dependent increases in both the magnitude and duration of intracorporal pressure, up to a maximum of 80 to 90% of mean arterial pressure. Furthermore, the presence of threshold concentrations of forskolin was shown to significantly augment the activity of PGE1 both in vitro (increased cAMP) and in vivo (increased pressure). Moreover, there were no detectable systemic effects following the intracorporal injection of forskolin or a mixture of forskolin and PGE1. CONCLUSIONS: These observations suggest that the use of forskolin, alone or in combination with other drugs that increase intracellular cAMP levels, might represent an attractive opportunity for improved and more rational development of next generation intracavernous pharmacotherapeutic agents.

The epidemiology of erectile dysfunction.

During the last two decades, significant advances have been made in the understanding of male sexual dysfunction. Concomitantly, a marked increase in both clinical and research activity in the field of male erectile dysfunction has led to a better evaluation and more treatment options. The prevalence and incidence are dependent on the definitions used, the diagnostic tolls, and the treatment options. Using standard definitions as suggested by the NIH Consensus Conference and improving our diagnostic and treatment options will have a major impact on the epidemiology of ED. A summary of the risk factors for ED is presented in Table 3. Still more epidemiologic research is essential to further understand the distribution as well as the prevalence of ED in certain ethnic groups, chronic conditions, and as a result of surgery and trauma. These studies will help us improve our diagnostic skills as well as our therapeutic options.