A. Calabro

Frequency and Determinants of Erectile Dysfunction in Italy

Objective: To analyze the prevalence and risk factors for erectile dysfunction (ED) in Italy in a cross–sectional study.Methods: Eligible for the study were men aged 18 years or more, randomly identified by 143 general practitioners among their registered patients during the period January 1996 to February 1997. ED was defined as the impossibility to achieve and maintain an erection sufficient for satisfactory sexual performance.Results: Of the 2,010 men interviewed, 257 (12.8%) reported ED. The prevalence increased with age, from 2% in men aged 18–39 to 48% in those >70 years (tested for trend, p = 0.0001). A history of cardiopathy, diabetes, hypertension, neuropathy, thrombotic/hemorrhagic stroke, peripheral vascular disorders, pelvic/medullary injury and pelvic surgery/radiation all increased the risk of ED. The association of hypertension and diabetes tends to increase the risk of ED. In comparison with nondiabetic and nonhypertensive men, the odds ratio (OR) was 1.4 (95% confidence interval (CI), 0.7–3.2) for hypertensive men without diabetes, 4.6 (95% CI, 1.6–13.7) for diabetic men without hypertension and 8.1 (95% CI, 1.2–55.0) for men with diabetes and hypertension. In comparison with never smokers, the OR of ED was 1.7 (95% CI, 1.2–2.4) for current smokers and 1.6 (95% CI, 1.1–2.3) for ex–smokers and increased with duration of the habit.Conclusions: The study offers a quantitative estimate of the prevalence of ED and of its main risk factors in Italian men.

Electrical Stimulation of The Dorsal Nerve of the Penis Evokes Reflex Tonic Erections of the Penile Body and Reflex Ejaculatory Responses in the Spinal Rat

An animal model using the spinal rat was characterized. Electrical stimulation of the dorsal nerve of the penis elicited reflex tonic erections of the penile body and reflex bulbospongiosus muscle activity, flips and ejaculations. The tonic erections of the penile body are independent from contractions of the bulbospongiosus muscle and appear to be the result of a neurovascular process. Our observations suggest that reflex bulbospongiosus muscle activity, flips and ejaculations are a single complex reflex response, which we define as reflex ejaculatory response. Two parameters predicted the occurrence and type of reflex response. The visualization of bulbospongiosus muscle activity during surgical isolation of the dorsal nerve of the penis was sufficient to anticipate the elicitability of reflex ejaculatory responses. The latter, together with a systemic systolic pressure > or = 73 mmHg., warranted the elicitability of reflex tonic erections. The similarities found in the physiology of rat tonic penile body erections and of human erections make this model promising for further elucidation of sexual function. Moreover, the present model may prove useful for the investigation of neurogenic erectile dysfunction, and of neurogenic ejaculatory disorders.

Reconstructive surgery of the urethra: a pilot study in the rabbit on the use of hyaluronan benzyl ester (Hyaff-11) biodegradable grafts

We investigated the outcome of reconstructive surgery of the urethra through guides composed of a novel biodegradable and highly biocompatible polymer, Hyaff-11. A tract of about 1.5 cm of the rabbit pendulous urethra was totally resected and replaced by a Hyaff-11 tubular graft. Eleven animals were analysed at each of the time points ranging from 7 days to 4 weeks following surgery. Histological and radiological evaluation showed a satisfactory remodelling of the neo-urethra around the implant. The regenerated connective tissue connected both urethral stumps within the first 7 days. On postoperative week 3, the Hyaff-11 guide had disappeared. At the 4-week time point the retrograde urethrogram showed a good distensibility of the neourethra. The regenerated stroma consisted of fibroblastic cells, and collagenous and elastic fibres. The neo-epithelium was pluristratified and exhibited cells of the cuboidal type.

Characterization of in vitro relaxant mechanisms in erectile tissue from rabbits of different ages

In the present study we investigated the in vitro relaxant response of erectile tissue obtained from rabbits of different ages (3, 7 and 24 months) in order to detect the progression with age of cavernosal activity in response to substances acting via endothelium-dependent or-independent mechanisms. Noradrenaline induced a concentration-dependent contraction (0.1 μM–3 mM), with an increase in the contractility in the 24-month-old group. Acetylcholine produced a concentration-dependent relaxant effect in the three age groups, with a reduction of the maximal relaxant effect in older animals. ATP (10 μM–1 mM) and adenosine (10 μM–1 mM) induced a concentration-dependent relaxant effect that was higher in the older group. The presence of the NO-synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) (0.1 mM) or of the P2-purinoceptor antagonist suramin did not affect ATP relaxation. Relaxation induced by sodium nitrite and nifedipine was reduced in older animals. In conclusion, aging selectively alters the in vitro responsiveness of rabbit erectile tissue. Purinergic system remains more active despite a decrease in the maximal endothelial cholinergic activity and the direct smooth muscle relaxant component.

A simplified in vitro preparation of the corpus cavernosum as a tool for investigating erectile pharmacology in the rat

This work describes a simple technique for the assessment of corpus cavernosum function in a species, the rat, representing a convenient model for basic research. We obtained measurable and reproducible responses to different pharmacological agents as well as to electrical field stimulation. In view of the present results we conclude that isolation of the erectile tissue together with the septum may constitute a valuable experimental tool for investigating both local erectile mechanisms and the action of drugs, in the rat corpus cavernosum. Data obtained in the presence of N-nitro-L-arginine and methylene blue further reinforce the concept that nitric oxide may be involved in the process of erection in the rats as well as in other animal species.

Functional response of cavernosal tissue to distension

We studied rabbit isolated erectile tissue responses to changes in preload and to active tension development with norepinephrine. The effects of antagonists of endothelin-1, prostaglandins E2 and F2αand of nitric oxide were also tested on normal and de-endothelialized preparations. Tissue distension was found to elicit spontaneous rhythmic contractions. Increase in preload diminished the latency of the spontaneous activity and augmented the developed force. Active tension development and the inhibitor of the Na+,K+ pump, ouabain, opposed the spontaneous activity. A marked reduction in the resting tension with abolition of the spontaneous activity was observed on normal, but not on de-endothelialized tissues, following the addition of the specific prostaglandin E2 and F2α receptor antagonist, SC-19220. At 3 × 10−4 M, the highest concentration used, the endothelin-A receptor antagonist BQ-123 failed to change the pattern of the spontaneous activity and the resting tension of normal tissues. The nitric oxide synthesis inhibitor, l-NAME, did not produce reliable effects. These findings point to a causal relation between cavernosal tissue distension and phasic and tonic contractions. Phasic contractions appear to be elicited by smooth muscle cells through the enzyme Na+,K+-ATPase. Increase in the resting tone could be mediated, at least in part, by the endothelium, through the release of prostaglandins E2 and/or F2αbut not of endothelins. We discuss the hypothesis that, in cavernosal tissue, mechanotransduction of distension to contractile responses is an important determinant of detumescence.

Bladder function in the aged rat: a functional and morphological study.

This study was designed to characterize urinary bladder function in the aged rat (27 months of age). For comparative purposes, two different control groups were included into the experimental protocol: normal 6-month old and hyperdiuretic 6-month old rats. Increased threshold volume for micturition and increased bladder mass were found in both aged and hyperdiuretic rats. No difference in the amplitude of micturition contractions was detected between groups. In the aged rat, but not in the hyperdiuretic one, augmented threshold volume and bladder mass were associated with increased intravesical pressure at micturition and structural changes of intramural bladder innervation. When activated, the vesicovesical reflex did not show any change in terms of rate of isovolumetric contractions. In the aged rat, altered sensory information on the state of maximum fullness seems to play an important role in determining abnormal cystometric findings.

Sarcomatous carcinoma of the kidney presenting as spontaneous retroperitoneal hemorrhage: report of a case with immunocytochemical study

A case of spontaneous perinephric hematoma due to a renal cell sarcomatous carcinoma in a 46-year-old woman is reported. Immunocytochemical analysis for the intermediate-sized filament proteins allowed a specific diagnosis of pseudosarcomatous renal carcinoma. Clinical, radiographic, sonographic and CT findings of spontaneous perinephric hematoma are discussed and the therapeutical modalities are briefly outlined.

Guiding spontaneous tissue regeneration for urethral reconstruction: long-term studies in the rabbit.

Abstract We designed long-term in vivo experiments to study rabbit urethral regeneration and remodelling over a hyaluronan biodegradable prosthesis. Seven months after the resection of a 1.5-cm-long tract of the urethra and its substitution with the prosthesis, radiological analysis showed the disappearance of the implant and the re-establishment of urethral continuity along the transmural defect. The regenerated tissue remodelled around the implant and exhibited good distensibility under pressure. Histological evaluation showed that the neo-urethra was lined with transitional epithelium and the stroma contained abundant elastic fibres. An examination of the pattern of the major cytoskeletal and cytocontractile proteins of smooth muscle cells and fibroblasts was able to distinguish fibroblasts from smooth muscle cells and myofibroblasts in the neo-urethra. These experiments provide evidence for the potential, successful use of biocompatible/bioresorbable devices for reconstructive surgery of the urethra.

CHRONIC TREATMENT WITH CYCLOSPORINE A IN NEW ZEALAND RABBIT : AORTIC AND ERECTILE TISSUE ALTERATIONS

Transplanted patients frequently present erectile impotence. In order to test any interference by cyclosporine A (CsA), which is commonly used in the post-transplantation management, we investigated the in vitro contractile and relaxant responses of corpus cavernosum and aorta from rabbits chronically treated with CsA. Male New Zealand White rabbits 6 months of age were treated with CsA (25 mg/kg per day s.c.) or solvent (corn oil) for 3 weeks. Descending thoracic aorta and erectile tissue were studied in vitro at the end of treatment. Isometric tension was recorded. In thoracic aorta, noradrenaline (0.1–30 mM) induced a concentration-dependent contraction with no difference betweer the two groups. Acetylcholine (30 mM–3 mM) produced relaxation (52±4% at 1 mM) that was significantly reduced in comparison to controls (67±4%, P<0.05). ATP (3–10 mM) relaxation was not significantly different (maximal 78±10% and 62±12% in CsA-treated and controls). The relaxation produced by sodium nitrite was reduced in CsA-treated rabbits (at 10 mM and 0.1 mM concentrations). In erectile tissue, no significant variation in the response of isolated erectile tissue to the above drugs was observed between CsA-treated and control animals. These data indicate that chronic treatment with CsA in rabbits, despite alteration of the in vitro response of thoracic aorta, does not directly influence the function of penile tissue with relaxants.