Dietary antioxidants improve arteriogenic erectile dysfunction.

Most cases of erectile dysfunction (ED) are associated with oxidative stress risk factors such as diabetes mellitus, smoking, hypercholesterolaemia and hypertension. Our goal was to search for markers of oxidative stress in arteriogenic ED and examine the protective role of dietary antioxidants. Atherosclerosis-induced ED was developed in rabbits by balloon de-endothelialization of the iliac arteries. Ballooned and age-matched control animals were assigned into subgroups receiving pomegranate extract antioxidants in drinking water or tap water as placebo. After 8 weeks, penile blood flow and erectile activity were recorded. Erectile tissue relaxation, oxidative products, oxidative stress-responsive genes and structure were examined using organ bath, enzyme immunoassay, quantitative real-time polymerase chain reaction and transmission electron microscopy, respectively. Arterial ballooning caused diffused atherosclerosis, decreased intracavernosal blood flow and led to ED. Impairment of endothelium-dependent relaxation, diffused fibrosis, increased oxidative products, upregulation of superoxide dismutase (SOD) and aldose reductase (AR) gene expression, mitochondrial and endothelial structural damage and increased caveolae were evident in erectile tissues from atherosclerotic animals receiving placebo. Upregulation of antioxidant enzymes SOD and AR failed to protect ischaemic erectile tissue from oxidative injury. Pomegranate extract significantly improved intracavernosal blood flow, erectile activity, smooth muscle relaxation and fibrosis of the atherosclerotic group in comparison with the atherosclerotic group receiving placebo, but did not normalize them to the age-matched control levels. Pomegranate extract appeared more effective in diminishing oxidative products, preventing SOD and AR gene upregulation, and protecting mitochondrial, endothelial and caveolae structural integrity of the atherosclerotic group. Our data suggest the presence of oxidative stress in ED and a more efficient action of antioxidants on molecular and ultrastructural alterations than on distinct functional deficit and structural damage in the ischaemic penis.

Frequent long-distance gene flow in a rare temperate forest tree (Sorbus domestica) at the landscape scale.

Precise empirical data on current gene flow by pollen, both with respect to distance and abundance, is crucial to understand whether habitat fragments are functionally connected. Based on a large-scale inventory ( approximately 100 km(2)) in which all individuals of a naturally scattered forest tree (Sorbus domestica) were mapped, we inferred current gene flow by pollen using genetic paternity analysis. We detected an extensive network of effective pollen transfer. Although short pollen flow distances were most abundant, 10% of the assigned pollen donors were more than 2 km away from their female mating partners, and 1.8% were even at a distance of 12-16 km. This latter pollen flow shows that current long-distance gene flow over a fragmented landscape clearly occurs. Pollen dispersal was well described by a fat-tailed inverse curve. Using parentage analysis of established trees, maternally inherited chloroplast markers and diameter at breast height measurements as an indicator of individual tree age, we were able to infer regular seed dispersal distances over several hundred metres up to more than 10 km. We conclude that in temperate, insect-pollinated and animal-dispersed tree species such as S. domestica, fragmented subpopulations are functionally connected by gene flow through both pollen and seed.

Hiatal hernia and Barrett's oesophagus impact on symptoms occurrence and complications.

UNLABELLED: The aim of the study was to evaluate the influence of sliding hiatal hernia over the Barrett's oesophagus, including symptoms rate and complications. METHODS: A total of 520 (4.6%) cases of Barrett's oesophagus were found out of 18.276 upper gastrointestinal endoscopies, performed in 11.276 patients at a single tertiary centre in a period from 1994 to 2004. RESULTS: Sliding hiatal hernia was found in 58% of patients with Barrett's oesophagus, more frequently in men (60%). The association between hernia and some complications of Barrett's oesophagus was significant (94% of Barrett's ulcer, 77% of low-grade dysplasia with p < 0.01). However, there was no significant association with adenocarcinoma (54%; p > 0.05). The other complications of Barrett's oesophagus (i.e. bleeding, stenosis, high-grade dysplasia) were identified in small number (less than 10), so they were not evaluated statistically. Association between the presence of hiatal hernia and occurrence of symptoms (reflux symptoms, dysphagia, odynophagia, dyspeptic and other symptoms) was significant with p < 0.01. CONCLUSIONS: Our study suggests that sliding hiatal hernia may play a significant role as a pathophysiologic factor in Barrett's oesophagus. Complications rate of Barrett's oesophagus were not equally frequent in particular cases with hiatal hernia. The occurrence of symptoms is getting more pronounced in those with sliding hiatal hernia.

Intestinal spirochaetosis: a rare histopathological diagnosis and potential light microscopic pitfall.

A case of intestinal spirochaetosis is described. Endoscopic specimens of a 52-year-old female revealed a blue basophilic margin of mucosal surface in haematoxylin-eosin stained sections. However, on ultrastructural level, moderate infestation of enterocytic brush border with spirochaetes was found. The pitfalls of histopathological diagnosis of spirochaetosis are discussed.

Alterations in angiogenic growth factors and neuronal nitric oxide synthase expression in chronic cavernosal ischemia.

Our aim was to study anatomical and molecular changes at varying time points after the induction of cavernosal ischemia (CI) in a rabbit model of arteriogenic erectile dysfunction. Tissue structure and the expression of angiogenic and neurogenic genes were examined using immunostaining and reverse transcription-polymerase chain reaction (RT-PCR) analyses. We found a progressive increase of erectile connective tissue together with a decrease in smooth muscle cell content as the duration of CI increased. Immunohistochemical staining showed an increase in vascular endothelial growth factor (VEGF) levels at the early stages and a decrease at the later stages of ischemia. RT-PCR analysis of VEGF and neuronal nitric oxide synthase (nNOS) confirmed these results and showed nearly a two-fold increase in VEGF and nNOS mRNA levels in the early stages of CI with a decrease at the later stages of CI. On the other hand, mRNA levels of VEGF receptor, KDR, decreased approximately by 50% over the course of CI. Our studies showed that the cellular and molecular responses of the erectile tissue to short-term ischemia are different than those seen after long-term ischemia. The dramatic reduction in KDR expression suggests that the cavernosal endothelium is very sensitive to ischemia. The similar changes in VEGF and nNOS expression over the course of CI suggest a tissue-defensive mechanism to CI via the VEGF and NO pathways. Taken together, this study suggests that supplementation of VEGF at earlier stages of ischemia may restore the damaged endothelial cells of the corpus cavernosum and support tissue perfusion.

The aging bladder.

Although it is well established that lower urinary tract symptoms increase in frequency with aging, there are few studies of the mechanisms that underlie bladder dysfunction. Age-related reduction in bladder capacity, uninhibited contractions, decreased urinary flow rate, diminished urethral pressure profile, and increased postvoid residual volume warrant investigation and require differentiation between symptoms associated with aging and those related to comorbid conditions. Here, the current data are reviewed, including those from muscle bath investigations of bladder tissue contractility, in vivo studies using animal models, and clinical studies in the aging population.

Treatment of patients with achalasia with botulinum toxin: a multicenter prospective cohort study.

Botulinum toxin (BT) injection is an alternative treatment of achalasia. The aim of the study was to examine outcomes of patients treated with BT in the Czech Republic. Since 1997, 49 patients with achalasia have been treated with BT. We prospectively evaluated the effect of BT injection on 41 patients during a median follow-up of 24 months (range 9-62). Esophageal manometry was performed before and at 3-5 months after the injection. In 16 patients, BT was injected from the antegrade angle only (subgroup A), in 15 patients, BT was injected from both retrograde and antegrade angles (subgroup B) and, in 10 patients, BT injection was combined with subsequent balloon dilatation (subgroup C). Immediate clinical response was achieved in 93% of patients. Clinical remission was sustained beyond 3 months in 83% of patients (responders). Fourteen responders (41%) did not experience a relapse during the median of 22 months. Twenty responders (59%) experienced symptomatic relapse approximately 8 months after the injection. Ten relapsers underwent BT reinjection, five (50%) of them were asymptomatic for another 14 months. The remaining five (50%) patients reported a second relapse approximately 6 months after the reinjection. Median duration of the symptom-free period was 11.5 months after the first BT injection, and 10.5 months after the second (P = 0.21). We did not find any significant predictor of a favorable outcome; responders tended to be older and to have a lower basal lower-esophageal-sphincter pressure. Patients in subgroup C were more likely to be in remission at 1 and 2 years as compared with patients in subgroup A. BT injection is an effective treatment of achalasia in the short term. However, almost 70% of patients experience a relapse within 2 years. BT injection should therefore be reserved for patients at risk for more invasive procedures or for patients who prefer this treatment.

[Intraoperative enteroscopy--personal experience from 1995 to 2002]. / Intraoperacní enteroskopie--vlastní zkusenosti z období 1995-2002.

Authors present their experience with the intraoperative enteroscopy method--an invasive technique of small bowel examination. It is performed under narcosis at an operating theatre (i.e. in co-operation with surgeon and anaesthesiologist). The endoscopy-performing physician becomes one of the members of the operating team. The advantage of the method is the possibility to examine of the whole small intestine and to solve immediately the pathological findings by endoscopic or surgical intervention. The examination is invasive and the correct indication is mandatory. Authors report their results of 18 intraoperative panendoscopies of small intestine.

[Epithelioid hemangiosarcoma of the thyroid gland]. / Epiteloidní hemangiosarkom stítné zlázy.

Authors present a case of epithelioid haemangiosarcoma of the thyroid gland in a 54-year-old female with a history of eufunctional nodular goitre. The patient was treated by total thyroidectomy with extirpation of cervical lymph nodes and by subsequent chemotherapy. The tumour behaved highly aggressively with early generalization and unusual way of metastatic spread into the wall of the stomach and duodenum. The patient died 3 months after the surgery due to therapeutically unmanageable bleeding into the GIT. The clinico-pathological aspects of the case are discussed.

[Effects of nonsteroidal anti-inflammatory agents on the gastrointestinal tract]. / Ucinky nesteroidních antiflogistik na gastrointestinální trakt.

Non-steroidal anti-inflammatory drugs (NSAID) belong to the most commonly used drugs worldwide. NSAIDs can cause serious side effects to the gastrointestinal tract. During NSAIDs treatment 10-12% patients suffer from dyspepsia. Up to 1% patients develop severe gastrointestinal complications (ulcer, bleeding, perforation). Any part of gastrointestinal tract could be affected. In oesophagus, NSAIDs can cause oesophagitis of fibrous stricture. NSAID gastropathy can be detected in 40% patients chronically treated with NSAIDs. NSAIDs toxic injury to small and large bowel is frequent but only seldom properly recognised. Serious hepatic lesions are rare. There is no fully reliable and sure prophylaxis or treatment of NSAIDs impairment of to the gastrointestinal tract. Rate of side effects can be reduced by reasonable prescriptions and by primary and secondary prophylaxis. Low rate of side effects is associated with the use of pro-drugs (compound is metabolised to an active substance after absorption from the gastrointestinal tract). New promising drugs were developed with dual action (5-lipoxygenase- and COX-inhibition) and NSAID releasing NO (nitronaproxen, nitrophenac). Specific COX-2 inhibitors (coxibes) provide comparable anti-inflammatory and analgesic effect but the risk of serious side effects to the gastrointestinal tract is significantly lower (when compared with non-specific NSAIDs). Beside harmful effects, NSAIDs are powerful tool in chemoprevention of colorectal cancer.

Primary retroperitoneal seminoma with utrasonically abnormal testes.

Primary retroperitoneal seminomas account for approximately 2% of all seminomas. Differentiating the primary retroperitoneal tumor from a metastatic tumor with an occult testicular primary remains difficult despite the availability of ultrasonic examination. We present a case of primary retroperitoneal seminoma with ultrasonically demonstrated abnormalities in both testes. The patient underwent a unilateral orchiectomy and ultrasound-guided biopsy of the opposite testis. All surgical specimens were negative for testis cancer. Controversial issues in the diagnosis and treatment of primary retroperitoneal germ cell tumors are discussed.

Chronic ischemia alters prostate structure and reactivity in rabbits.

PURPOSE: Autopsy studies performed in men older than 80 years old have demonstrated that 90% have histological evidence of benign prostatic hyperplasia. Despite this fact pressure flow studies in men of this age who are referred for the evaluation of lower urinary tract symptoms have shown that only 40% have evidence of bladder outlet obstruction. To our knowledge the specific features of benign prostatic hyperplasia responsible for bladder outlet obstruction are not known. To investigate the possible etiological factors responsible for bladder outlet obstruction we determined whether chronic ischemia alters the structural and functional properties of the prostate. MATERIALS AND METHODS: Male New Zealand White rabbits weighing 3.5 to 4 kg. were divided into a chronic prostate ischemia (12), hypercholesterolemia (8) and age matched control (8) group. The chronic prostate ischemia group underwent balloon endothelial injury of the iliac arteries and received a 0.5% cholesterol diet, the hypercholesterolemia group received a 0.5% cholesterol diet only and controls received a regular diet. After 12 weeks using anesthesia iliac artery and prostatic blood flow was measured by an ultrasonic and laser Doppler flowmeter, respectively. The animals were then sacrificed and the prostate was processed for histological evaluation, immunohistochemical staining for vascular endothelial growth factor expression and organ bath studies. RESULTS: Iliac artery and prostatic blood flow was significantly decreased in the chronic prostate ischemia compared with the hypercholesterolemia and control groups. Histological findings included thickening and fibrosis of the prostatic stroma and cystic atrophy of the epithelium in the chronic prostate ischemia group as well as minor thickening of the stroma in the hypercholesterolemia group. These structural changes correlated with decreased vascular endothelial growth factor expression. Organ bath studies showed that chronic ischemia and to a lesser extent hypercholesterolemia impaired electrical field stimulation induced neurogenic relaxation of the prostatic tissue. Neurogenic relaxation of the prostatic tissue was improved by combined treatment with indomethacin and L-arginine in the hypercholesterolemia but not in the chronic prostate ischemia group. Nitric oxide donor sodium nitroprusside produced comparable relaxation in all 3 groups. CONCLUSIONS: Chronic ischemia causes marked changes in prostatic structure and contractility. Ischemia induced glandular atrophy was consistently associated with decreased vascular endothelial growth factor expression. Decreased relaxation of the ischemic tissue to electrical field stimulation appears to involve the nitric oxide pathway. The nitric oxide precursor L-arginine reversed hypercholesterolemia induced impairment of prostatic tissue relaxation. Our study suggests that chronic ischemia results in thickening and fibrosis of the prostate, changing its mechanical properties. Chronic ischemia also impairs neurogenic relaxation in the prostate. We discuss the possible relationship of these changes to clinical bladder outlet obstruction.

Importance of the anorectal manometry in chronic anal fissure.

This publication presents the results of postoperative manometric investigations of 77 patients with anal fissure treated within the time span 1985-1997 by lateral sphincterotomy (LS). Results of manometric investigations are compared with digital anal examinations and subjective complaints of patients. Digital anal examination correlated with manometry results in 52 cases (68%). The correspondence between these two results was proved in 48 cases when normal finding was present. An increased sphincter tonus was found in 3 patients, all of them having the anal fissure recurrences. A marked sphincters insufficiency, which had been manifested by stool and gas incontinence was found in one case. When searching for the reason of this complication we found out that this operation procedure had been performed by an unexperienced team of surgeons. In 25 cases (32%) the digital anal assessment and manometric measurement were different. Nevertheless, the clinical symptoms in this group of patients were rather poor. To conclude we may state that manometry provides important data for preoperative evaluation of anal sphincter function and should be performed prior to lateral sphincterotomy operation at least in women.

Systemic administration of apomorphine improves the hemodynamic mechanism of clitoral and vaginal engorgement in the rabbit.

Clitoral and vaginal engorgement during sexual stimulation depend in part on the increase of arterial inflow. It has been shown that apomorphine (APO), a non-selective dopamine receptor agonist, produces penile erection by activating dopaminergic receptors in the central nervous system. Our aim was to study whether systemic administration of APO improves the hemodynamic mechanism of clitoral and vaginal engorgement in the rabbit. Female New Zealand white rabbits (3.5-4 kg, n=6) were anesthetized. To examine sexual arousal function, the vaginal/clitoral branch of the pelvic nerve was stimulated electrically and maximal increases in clitoral intracavernosal and vaginal wall blood flows and pressures were recorded. After this APO was injected intravenously in a dose-response manner (0.05, 0.1, 0.2, 0.3 and 0.4 mg/kg) and nerve stimulation was performed after each dose. Changes in nerve-stimulated increase of clitoral intracavernosal and vaginal blood flows and pressures after APO was compared to those recorded before APO. Electrical stimulation of the vaginal/clitoral branch of the pelvic nerve significantly increased clitoral intracavernosal and vaginal wall blood flows in the rabbit. Intravenous administration of APO caused concentration dependent increase in nerve stimulation-induced peak clitoral intracavernosal and vaginal wall blood flows reaching to statistically significant at the concentration of 0.1 and 0.2 mg/kg. Inravenous administration of APO greater than 0.2 mg/kg (0.3 and 0.4 mg/kg) were less effective or produced adverse effects on clitoral intracavernosal and vaginal wall blood flows. Intravenous APO also tended to increase nerve-stimulated increase of clitoral intracavernosal and vaginal wall pressures, but the effect was not statistically significant. In conclusion, our studies suggest that systemic administration of APO may improve clitoral and vaginal engorgement by increasing clitoral intracavernosal and vaginal wall arterial inflow.

Atherosclerosis-induced chronic arterial insufficiency causes clitoral cavernosal fibrosis in the rabbit.

In our previous studies we found that aging-associated fibrosis of clitoral cavernosal tissue correlated with the prevalence of cardiovascular disease in elderly women. The aim of this study was to determine specifically, arterial insufficiency-related structural changes of clitoral cavernosal tissue in a rabbit model. New Zealand white female rabbits were divided into clitoral cavernosal ischemia (CCI, n = 5) and control (n = 5) groups. The CCI group underwent balloon endothelial injury of the iliac arteries and received 0.5% cholesterol diet. The control group received a regular diet. After 16 weeks, arteriography was performed then the animals were sacrificed. The iliac arteries and the entire clitoris were removed. Cross-sections of the iliac arteries and clitoris were processed for histologic evaluation The percentage of smooth muscle and connective tissue in trichrome stained sections of clitoral cavernosal tissue was determined by computer-assisted histomorphometry. Arteriography revealed diffused occlusive disease in the common iliac, internal iliac and pudendal arteries in the CCI group. Histology showed that arterial occlusive disease spreads from the site of balloon injury to the smaller branches involving the clitoral cavernosal arteries. Diffuse fibrosis was observed in the clitoral cross-sections of the CCI group. The percentage of clitoral cavernosal smooth muscle (mean +/- standard error) in the CCI group (53% +/- 0.9%) was significantly decreased compared with the control group (62% +/- 0.8%) (P = 0.0001). Chronic clitoral cavernosal ischemia causes significant fibrosis and loss of smooth muscle in the clitoral cavernosal tissue. These findings suggest that chronic clitoral cavernosal arterial insufficiency may play a role in the pathophysiology of female sexual arousal disorders.

Isoprostane 8-epi PGF2alpha, a product of oxidative stress, is synthesized in the bladder and causes detrusor smooth muscle contraction.

Isoprostane 8-epi PGF2alpha is a product of oxidative stress that causes potent smooth muscle contraction. Its production increases in conditions associated with oxidative stress such as in diabetes, smoking, and aging. The aim was to study whether the urinary bladder synthesizes isoprostane 8-epi PGF2alpha and releases to the urine and whether isoprostane 8-epi PGF2alpha causes bladder smooth muscle contraction. Urine samples were obtained transurethrally from 12 male New Zealand white rabbits for measurement of isoprostane 8-epi PGF2alpha levels. To examine whether bladder synthesizes isoprostane 8-epi PGF2alpha, both ureters were ligated, then the bladder was washed 5 times by filling and emptying with normal saline. Bladder was refilled with normal saline, and at 5 minutes a bladder washout sample was taken. After this, the bladder was contracted by nerve stimulation periodically for 30 minutes, and then another washout sample was taken. Strips of bladder tissues were processed for study of isoprostane 8-epi PGF2alpha production in tissue culture chambers and for isometric tension measurements in the organ bath. Enzyme immunoassay (EIA) revealed a remarkable amount of isoprostane 8-epi PGF2alpha in the rabbit urine. EIA of washout samples showed that the bladder synthesizes isoprostane 8-epi PGF2alpha and its production increases with nerve stimulation-induced contractions. EIA of samples from the tissue culture media showed that bladder strips synthesize isoprostane 8-epi PGF2alpha in vitro. Electrical field stimulation (EFS) significantly increased the synthesis and release of isoprostane 8-epi PGF2alpha by the bladder strips. In the organ bath, isoprostane 8-epi PGF2alpha caused concentration-dependent contraction of bladder tissue. While the threshold contraction required smaller concentration of isoprostane 8-epi PGF2alpha (3 nmol) than carbachol (10 nmol), the amplitude of contraction to carbachol was greater than isoprostane 8-epi PGF2alpha. Our studies show that the rabbit bladder synthesizes isoprostane 8-epi PGF2alpha and releases it to the urine. Production of isoprostane 8-epi PGF2alpha in the bladder increases with nerve stimulation-induced contraction. Exogenous isoprostane 8-epi PGF2alpha causes significant bladder smooth muscle contraction. Our findings necessitate further studies to evaluate the possible role of oxidative stress and increased isoprostane 8-epi PGF2alpha production in bladder dysfunction. Neurourol. Urodynam. 19:43-51, 2000.

Overactivity and structural changes in the chronically ischemic bladder.

PURPOSE: Our aim was to study the effect of chronic ischemia on bladder contraction and detrusor smooth muscle reactivity. The relationship between structural damage and functional changes in the chronically ischemic bladder was also investigated. MATERIAL AND METHODS: Male New Zealand White rabbits were divided into arterial injury (AI), hypercholesterolemia (Hch) and control groups. The AI group (n = 18) underwent balloon endothelial injury of the iliac arteries and received a 0.5% cholesterol diet. The Hch group (n = 8) received a 0.5% cholesterol diet alone. The control group (n = 8) received a regular diet. After 16 weeks, iliac artery and bladder wall blood flows were recorded. Cystometrograms and arteriography were obtained and bladder tissues were processed for isometric tension measurement in the organ bath and for histological evaluation. RESULTS: At 16 weeks, blood flow through the iliac arteries was significantly reduced in the AI group compared with the Hch and control groups. In the AI group, 8 animals developed severe bladder ischemia (SBI) defined as greater than 60% decrease in bladder blood flow, 7 animals developed moderate bladder ischemia (MBI) defined as 40 to 60% decrease in bladder blood flow, and 3 animals failed to develop significant bladder ischemia (<40% decrease in bladder blood flow). In the control animals, bladder blood flow increased prior to contraction, decreased during contraction and rebounded to baseline levels after contraction. In animals with MBI and SBI, the increase in bladder blood flow prior to contraction and the rebound of blood flow after contraction, both seen in control animals, were diminished. Detrusor overactivity (significant increase in the frequency of spontaneous bladder contractions) was observed in the MBI group and impaired bladder contraction in the SBI group. In the organ bath, bladder strips from the MBI group demonstrated increased contractile response to carbachol and electrical field stimulation (EFS) while bladder strips from the SBI group showed impaired contractility. Hch alone produced only short-lived ischemia during bladder contraction and caused significantly lesser functional changes compared with those seen in MBI. Histological examination showed atherosclerotic occlusion in the iliac arteries and bladder microcirculation and marked disruption of urothelium in the MBI and SBI groups. Severe fibrosis was seen in bladder tissue from the SBI group, moderate fibrosis in tissue from the MBI group and mild fibrosis in tissue from the Hch group. CONCLUSIONS: Our studies show that chronic MBI is associated with detrusor overactivity and increased smooth muscle contractility to carbachol and EFS while chronic SBI is associated with impaired detrusor contraction. The mechanism of chronic ischemia-induced bladder dysfunction is not known and may involve multiple physiologic and structural changes in the bladder nerves, receptors and contractile components. Our studies suggest that ischemia-induced structural damage in the urothelium and possible chronic exposure of the underlying tissue and nerves to the urine may also play a role in MBI-induced detrusor overactivity. SBI-induced impairment of bladder contraction may involve, in part, extensive fibrosis and loss of bladder smooth muscle. Histopathophysiologic changes in bladder tissue from our MBI model are similar to those seen in patients with detrusor instability, suggesting that chronic ischemia may play a role in the development of idiopathic detrusor instability.

Atherosclerosis-induced chronic ischemia causes bladder fibrosis and non-compliance in the rabbit.

PURPOSE: The overall goal was to determine whether chronic ischemia and hypercholesterolemia interfere with bladder function and structure. The roles of atherosclerosis-induced chronic ischemia and hypercholesterolemia in bladder fibrosis and non-compliance were studied in the rabbit. The relationship between ischemia-induced changes in the expression of transforming growth factor-beta1 (TGF-beta1) and basic fibroblast growth factor (bFGF) and the severity of bladder fibrosis was also investigated. MATERIALS AND METHODS: Male New Zealand White rabbits were divided into chronic bladder ischemia (CBI, n = 11), hypercholesterolemia (Hch, n = 8) and control (n = 8) groups. The CBI group underwent balloon endothelial injury of the iliac arteries and received a 0.5% cholesterol diet. The Hch group received a 0.5% cholesterol diet alone. The control group was placed on a regular diet. After 16 weeks, iliac artery and bladder wall blood flow measurements, cystometrograms (CMG) and aorto-iliac arteriograms were obtained in all animals. Iliac arteries and bladder tissues were processed for histological staining and computer-assisted histomorphometric image analysis. The expressions of TGF-beta1 and bFGF in bladder tissue were determined by immunohistochemical staining utilizing monoclonal antibodies. RESULTS: At 16 weeks, arteriography and histology showed significant diffuse atherosclerotic occlusive disease of the aorto-iliac arteries in the CBI group. Iliac artery and bladder wall blood flows were significantly decreased in the CBI group compared with the Hch and control groups. Atherosclerosis-induced CBI shifted the volume-pressure curve to the left and caused severe bladder fibrosis. Hypercholesterolemia also caused fibrosis and non-compliance but to a much lesser extent compared with those caused by CBI. In histomorphometry, the percentage of detrusor smooth muscle was moderately decreased in the Hch group and severely decreased in the CBI group compared with the control group. In immunohistochemical stains of bladder tissues, bFGF expression was similar in the three groups of animals. TGF-beta1 expression was significantly greater in bladder tissues from the CBI group compared with the Hch and control groups. CONCLUSIONS: Our studies show that atherosclerosis-induced chronic ischemia increases TGF-beta1 expression in the bladder leading to fibrosis, smooth muscle atrophy and non-compliance. Hypercholesterolemia also interferes with bladder structure and compliance but to a significantly lesser extent compared with CBI. Our studies suggest that arterial insufficiency and hypercholesterolemia, common aging-associated disorders, may play important roles in the pathophysiology of voiding dysfunction in the elderly.

Relative roles of cyclooxygenase and nitric oxide synthase pathways in ischemia-induced increased contraction of cavernosal smooth muscle.

PURPOSE: To study the mechanism of chronic ischemia-induced increased cavernosal smooth muscle contraction in an animal model of vasculogenic erectile dysfunction. MATERIALS AND METHODS: New Zealand White rabbits were divided into control (n = 6, fed with a regular diet), hypercholesterolemic (n = 9, fed with a diet containing 0.5% cholesterol) and chronic cavernosal ischemia (CCI, n = 10, underwent balloon de-endothelialization of iliac arteries and received a diet containing 0.5% cholesterol) groups. After 16 weeks, the relationship between iliac artery blood flow and cavernosal smooth muscle contraction was studied. The roles of cyclooxygenase and nitric oxide (NO) pathways in chronic ischemia-induced increased smooth muscle contraction were also examined. RESULTS: Iliac artery blood flow in the CCI group was significantly reduced compared with the control and hypercholesterolemic groups. Hypercholesterolemia alone did not affect cavernosal smooth muscle contraction. Atherosclerosis-induced chronic cavernosal arterial insufficiency did not affect contraction to norepinephrine while causing a significant increase in electrical field stimulation-induced neurogenic contraction. Inhibition of the cyclooxygenase pathway by indomethacin decreased electrical field stimulation-induced contraction in all animals but failed to normalize the differences between CCI and control groups. In the presence of indomethacin, L-arginine decreased electrical field stimulation-induced contraction in the control and hypercholesterolemic groups but not in the CCI group. In the presence of indomethacin, treatment with nitric oxide synthase (NOS) inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), increased electrical field stimulation-induced contraction in all groups. This effect of L-NMMA on smooth muscle contraction was significantly greater in the control and hypercholesterolemic groups compared with the CCI group. After tissue treatment with L-NMMA, the magnitude of contraction in cavernosal tissue from control and hypercholesterolemic groups was similar to those observed in the CCI group. CONCLUSIONS: Mechanism of chronic ischemia-induced increased cavernosal smooth muscle contraction involves increased output of constrictor eicosanoids and impairment of the inhibitory influence of NO pathway in cavernosal tissue.