Tetrahydrobiopterin prevents chronic ischemia-related lower urinary tract dysfunction through the maintenance of nitric oxide bioavailability.

This study aimed to investigate the influence of chronic ischemia on nitric oxide biosynthesis in the bladder and the effect of administering tetrahydrobiopterin (BH4), a cofactor for endothelial nitric oxide synthase (eNOS), on chronic ischemia-related lower urinary tract dysfunction (LUTD). This study divided male Sprague-Dawley rats into Control, chronic bladder ischemia (CBI) and CBI with oral BH4 supplementation (CBI/BH4) groups. In the CBI group, bladder capacity and bladder muscle strip contractility were significantly lower, and arterial wall was significantly thicker than in Controls. Significant improvements were seen in bladder capacity, muscle strip contractility and arterial wall thickening in the CBI/BH4 group as compared with the CBI group. Western blot analysis of bladder showed expressions of eNOS (p = 0.043), HIF-1α (p < 0.01) and dihydrofolate reductase (DHFR) (p < 0.01), which could regenerate BH4, were significantly higher in the CBI group than in Controls. In the CBI/BH4 group, HIF-1α (p = 0.012) and DHFR expressions (p = 0.018) were significantly decreased compared with the CBI group. Our results suggest that chronic ischemia increases eNOS and DHFR in the bladder to prevent atherosclerosis progression. However, DHFR could not synthesize sufficient BH4 relative to the increased eNOS, resulting in LUTD. BH4 supplementation protects lower urinary tract function by promoting eNOS activity.

Therapeutic effects of Choreito, a traditional Japanese (Kampo) medicine, on detrusor overactivity induced by acetic acid in rats.

Choreito (CRT), a traditional Japanese (Kampo) medicine, is widely used for the treatment of overactive bladder (OAB) and other lower urinary tract symptoms in Japan. This study aimed to identify the effects and therapeutic mechanism of CRT on the improvement of detrusor overactivity (DO) using an experimental rat model. Forty-five female Sprague-Dawley rats were equally divided into three groups: intravesical saline instillation with normal food (normal group), intravesical acetic acid (AA) instillation with normal food (AA group), and intravesical AA instillation with CRT (AA with CRT group). To induce a decrease in bladder capacity, instillation of 0.2% AA was used based on prior studies. Cystometric investigation was employed to clarify the effects of AA and CRT. Microcirculation was performed using a laser blood flowmeter, and the localization of hypoxia-inducible factor 1α (HIF1α) was assessed by immunohistochemistry. The bladder capacities of the normal, AA, and AA with CRT groups were 1.2 ± 0.3 mL, 0.4 ± 0.1 mL, and 0.8 ± 0.1 mL, respectively. CRT significantly attenuated AA irritation of the urinary bladder and exerted protective effects on basal pressure, micturition pressure, micturition interval, and micturition volume. Furthermore, CRT could prevent the excess blood flow and edematous change under the urothelium induced by intravesical AA instillation. No obvious changes in immunohistochemical HIF1α staining were observed among the groups. CRT attenuated DO induced by intravesical AA instillation in a rat experimental model. CRT might impart therapeutic effects on OAB via the mitigation of urothelial damage and regulation of excess blood flow.

Spinal glycinergic and gamma-aminobutyric acid-ergic neurons inhibit the micturition reflex after electrical stimulation of the perineum in rats with pelvic venous congestion.

OBJECTIVES: To examine whether electrical stimulation of the perineum inhibited urinary frequency in rats with pelvic venous congestion, and whether electrical stimulation influences spinal glycinergic/gamma-aminobutyric acid-ergic neurons. METHODS: Bilateral common iliac veins and bilateral uterine veins were ligated to create pelvic venous congestion rats. At 4 weeks after ligation, cystometry was carried out before and after electrical stimulation with/without intrathecal injection of strychnine (a glycine receptor antagonist) and/or bicuculline (a gamma-aminobutyric acid type A receptor antagonist). In addition, measurement of amino acid levels in the lumbosacral cord was carried out with/without electrical stimulation, and cystometry was carried out after oral administration of glycine. RESULTS: Continuous cystometry showed that the interval between bladder contractions was shorter in pelvic venous congestion rats than in sham rats. Electrical stimulation did not change cystometric parameters in sham rats, but the interval between bladder contractions was increased by electrical stimulation in pelvic venous congestion rats. Electrical stimulation increased the levels of glutamic acid, glycine, gamma-aminobutyric acid, and taurine in the lumbosacral cord of pelvic venous congestion rats. Intrathecal strychnine abolished the effects of electrical stimulation in pelvic venous congestion rats, and intrathecal administration of both strychnine and bicuculline shortened the interval between bladder contractions more than before electrical stimulation. Oral administration of glycine (3%) to pelvic venous congestion rats increased bladder capacity. CONCLUSIONS: Electrical stimulation of the perineum inhibits urinary frequency mainly through activation of spinal glycinergic neurons, and partly through activation of gamma-aminobutyric acid-ergic neurons in a rat model of pelvic venous congestion.

[USE OF PHYTO- AND PELOIDOTHERAPY IN TREATMENT AND PREVENTION OF CHRONIC CYSTITIS IN WOMEN].

The article presents the findings of herbal- and peloidotherapy as a combination treatment inpatientswith chronic cystitis. The effectiveness of treatment was evaluated by the dynamics of clinical findings, results of laboratory and instrumental studies (increase functional bladder capacity, improvement / normalization of urinalysis, elimination of bacteriuria, improvement of microcirculation). The results showed high efficiency of phytoplankton and pelotherapy in normalization of urodynamics and microcirculation of the bladder mucosa. Upgraded combination scheme for the treatment of chronic cystitis significantly improved patient outcomes.

The Impact of Increased Bladder Blood Flow on Storage Symptoms after Holmium Laser Enucleation of the Prostate.

In order to investigate how holmium laser enucleation of the prostate (HoLEP) improves urinary storage symptoms, we assessed blood flow in the urinary bladder mucosa of patients with benign prostatic hyperplasia (BPH) before and after laser surgery. Seventy-four consecutive patients with BPH (median age 69 years, range; 53-88) underwent HoLEP at our institution and are included in this study. We prospectively assessed the International Prostate Symptom Score (IPSS), IPSS-QOL Score, the Overactive Bladder Symptom Score (OABSS), uroflowmetry, and blood flow in the urinary bladder, before and after surgery. Blood flow in the bladder mucosa was measured using the OMEGA FLOW (OMEGAWAVE, Tokyo, Japan) laser Doppler flowmeter. The median volume of the enucleated adenomas was 45.0 g (range: 25.0 to 83.2). The median IPSS improved significantly from 20 (range: 6-35) to 3 (0-22) (p < 0.001; Wilcoxon signed-rank test), as did the storage symptoms score, which decreased from 13 (2-20) to 3 (1-8) (p < 0.001). Median bladder blood flow increased at the trigone from 9.57 ± 0.83 ml/sec to 17.60 ± 1.08 ml/sec. Multiple regression analysis for the improved storage symptom score eliminated all explanatory variables except increased bladder perfusion. The data suggest that HoLEP improves blood flow in the bladder mucosa, which independently leads to the improvement of storage symptoms.

Microcirculation and structural reorganization of the bladder mucosa in chronic cystitis under conditions of ozone therapy.

Structural reorganization of the bladder mucosa in chronic cystitis and its correction by ozone therapy were studied. A relationship between the epithelial layer restructuring of different kinds (dystrophy, metaplasia, and degeneration), level of cell proliferation, and ultrastructural organization of urotheliocytes was detected. This complex of structural reactions was combined with dysregulation of tissue bloodflow in the bladder mucosa, shown by laser Doppler flowmetry. Positive structural changes were most marked in intravesical and less so in parenteral ozone therapy added to the therapeutic complex and manifested in reduction of inflammation and alteration in parallel with more intense reparative reactions. A special feature of parenteral ozone therapy was a significant improvement of microcirculation in the bladder mucosa.

Effect of ovariectomy, 17-beta estradiol, and progesterone on histology and estrogen receptors of bladder in female partial bladder outlet obstruction rat model.

AIM: The aim of this study was to investigate the effect of bilateral ovariectomy (OVX), 17-beta estradiol (E2), and progesterone (P4) on the histology and estrogen receptor (ER) expression of the bladder using a female partial bladder outlet obstruction (pBOO) rat model. MATERIAL AND METHODS: A total of 60 female Sprague-Dawley rats were evenly assigned into six groups of 10 each. Group A served as the control. Groups B-F underwent induced pBOO. Groups C-F underwent OVX. Groups D-F were given E2 (0.1 mg/kg/day), Group E was given P4 (1 mg/kg/day), and Group F was given P4 and dehydroepiandrosterone (DHEA) (300 µg/kg/day) by an Alzet pump. Four weeks later, serum E2 and P4 levels were evaluated. Each rat was anesthetized and the urinary bladder was removed for weighing and histological study. RESULTS: Expression of ER-ß was not significantly different between the control group and the other study groups. pBOO was shown to increase both bladder weight and detrusor muscle thickness. OVX had an additive effect to BOO on increased blood vessel density in the bladder. E2 was shown to increase blood vessel density, while P4 supplementation decreased blood vessel density. DHEA did not cause any significant effects on blood vessel density. CONCLUSION: Hormone therapy did not change the expression of ER in bladder outlet obstruction. Estradiol stimulated the increased angiogenesis of the bladder detrusor but P4 decreased the angiogenesis of the bladder detrusor. DHEA had no effect on the bladder detrusor.

Effect of melatonin on chronic bladder-ischaemia-associated changes in rat bladder function.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There are many studies showing melatonin's potent endogenous free radical scavenging and antioxidative properties, which protect against oxidative insult, but there is no information about the effect of chronic treatment with melatonin on oxidative-stress-related bladder dysfunction caused by chronic ischaemia. The model used in this study shows that functional and morphological changes caused by chronic bladder ischaemia and oxidative stress were protected by chronic treatment with melatonin, resulting in improvement of bladder hyperactivity. OBJECTIVE: To investigate the potential therapeutic benefit of melatonin for chronic ischaemia-related bladder dysfunction. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were divided into control, arterial injury (AI), AI with low-dose melatonin treatment (AI-ML) and AI with high-dose melatonin treatment (AI-MH) groups. The AI, AI-ML and AI-MH groups underwent a procedure to induce endothelial injury of the iliac arteries and received a 2% cholesterol diet after AI. The rats in the AI-ML and AI-MH groups were treated with melatonin 2.5 or 20 mg/kg/day orally for 8 weeks after AI. The control group received a regular diet. After 8 weeks, urodynamic investigations were performed. Bladder tissues and iliac arteries were processed for pharmacological studies, and for immunohistochemical and histological examination. RESULTS: Iliac arteries from AI, AI-ML and AI-MH rats displayed neo-intimal formation and luminal occlusion. In the AI group, the micturition interval was significantly shorter, and bladder capacity and voided volume were lower than in the controls. Contractile responses of bladder strips to KCl, electrical field stimulation and carbachol were significantly lower after AI than in the controls. The AI bladders were found to have a significantly increased collagen ratio, oxidative stress and inducible nitric oxide synthase (NOS) expression, and decreased constitutive NOS expression compared with the controls. In the AI-ML and AI-MH groups, neo-intimal formation was not prevented, but there were beneficial effects on bladder function and morphology. In the AI-ML group, the beneficial effects failed to reach statistical significance. In the AI-MH group, melatonin significantly improved oxidative stress and NOS expression, and there were significant improvements in all the functional and morphological variables compared with the AI group. CONCLUSIONS: Arterial occlusive disease may lead to chronic bladder ischaemia and bladder hyperactivity associated with oxidative stress. In the model used, chronic treatment with melatonin protected bladder function and morphology, probably through its free radical scavenging and antioxidative properties. Melatonin may prevent oxidative damage and improve ischaemia-related bladder dysfunction.

Nutritional supplementation with L-arginine prevents pelvic radiation-induced changes in morphology, density, and regulating factors of blood vessels in the wall of rat bladder.

PURPOSE: To determine whether L-arginine has protective effects against radiation-induced alterations in the morphology and regulatory factors of vesical blood vessels in rats. METHODS: Male rats aged 3-4 months were divided into groups of 10 animals each: (a) controls, consisting of non-treated animals; (b) radiated-only rats; and (c) radiated rats receiving L-arginine supplementation. Radiation was in one session of 10 Gy and was aimed at the pelvic-abdominal region. L-arginine was administered once a day (0.65 g/kg body weight), starting 7 days before radiation and continuing until killing on the 16th day after radiation. The density, relative area, and wall thickness of blood vessels were measured in the vesical lamina propria using histological methods, and the expression of vascular endothelial growth factor (VEGF) and fibroblast growth factors (FGF) in the bladder wall was assessed by RT-PCR. RESULTS: Compared with controls, radiation alone decreased the density and relative area of blood vessels by 32 % (p < 0.01) and 25 % (p < 0.05), respectively, and reduced the arterial wall thickness by 42 % (p < 0.004). VEGF and FGF mRNA levels after radiation were diminished by 67 % (p < 0.002) and 56 % (p < 0.04), respectively. The radiated animals supplemented with L-arginine were not significantly different from controls. CONCLUSIONS: Pelvic radiation leads to significant vesical modifications, as in the morphology of blood vessels and in VEGF and FGF expression. All these changes, however, were prevented by L-arginine treatment. These results emphasize, therefore, the potential use of this amino acid as a radioprotective drug.

Effect of the phytotherapeutic agent eviprostat on the bladder in a rat model of bladder overdistension/emptying.

AIMS: Ischemia-reperfusion injury is an important factor in the development of lower urinary tract symptoms (LUTS) that is partly mediated by the generation of free radicals. We investigate the effect of the phytotherapeutic agent Eviprostat, a treatment for benign prostatic hyperplasia (BPH) that has antioxidant and anti-inflammatory activity, on urinary bladder blood flow (BBF), and function in a rat model of bladder overdistension and emptying (OE). METHODS: For 8 days before surgery, OE rats received daily oral Eviprostat (36 mg/kg/day) or vehicle, while sham-operated animals received vehicle. The bladder was distended by infusion of saline over a period of 2 hr (overdistension) and then emptied. After 24 hr, BBF was measured with a laser speckle blood flow imager. The oxidative-stress marker malondialdehyde (MDA), proinflammatory cytokines, and myeloperoxidase were determined in the isolated bladder, and histological analysis was performed. Functional contractile responses of bladder strips to electrical field stimulation, carbachol, and KCl were measured. RESULTS: Twenty-four hours after bladder OE, a significant decrease in BBF and significant increases in bladder weight, malondialdehyde, proinflammatory cytokines, and myeloperoxidase were observed. Eviprostat almost completely prevented these changes. Histological analysis of the bladder of OE rats showed hemorrhage, accumulation of leukocytes, desquamation of epithelium, and edema, and Eviprostat suppressed these changes. The reduction in functional contractile forces in the bladder of OE rats was also prevented by Eviprostat. CONCLUSION: Eviprostat-mediated suppression of increased bladder oxidative stress and inflammation caused by bladder OE may contribute to the improvement of BBF and bladder function by Eviprostat.

The effects of posterior tibial nerve stimulation on refractory overactive bladder syndrome and bladder circulation.

AIM: We aimed to evaluate if posterior tibial nerve stimulation (PTNS) exerts its effects on overactive bladder symptoms through changes in bladder circulation. MATERIALS AND METHODS: Eighteen women who applied to Istanbul Medical Faculty with symptoms of urgency, frequency±urge incontinence and did not respond to anticholinergic treatment and behavioral modification were enrolled in the study. Weekly PTNS in 30-min sessions for 12 weeks was performed. Urogynecologic symptom assessment, 1-h pad test, bladder diary, King's Health Questionnaire (KHQ), and transvaginal Doppler ultrasonography were performed before and after treatment. RESULTS: Ten patients (55.5%) were cured, five (27.8%) improved, and no effect was observed in three (16.7%). No significant change was observed in systolic and diastolic flow rate, pulsatility index, resistive index, systolic/diastolic ratio and average flow rate. Significant decrease in frequency, urgency, urge incontinence, pad test results and increase in fluid intake was observed. There was a significant improvement in physical limitations and sleeping/energy domains of KHQ. No significant change was observed in urodynamics. CONCLUSIONS: PTNS does not have any effect on the bladder circulation despite positive effects on bladder diary, pad test, and quality of life in overactive bladder syndrome.

Nicorandil ameliorates hypertension-related bladder dysfunction in the rat.

AIMS: There is increasing evidence that ischemia is one of the main etiology in overactive bladder (OAB), and that nicorandil prevents OAB. We investigated the effect of nicorandil on hypertension-related bladder dysfunction in spontaneously hypertensive rats (SHRs). METHODS: Twelve-week-old SHRs received six-weeks treatment with nicorandil (0, 3, or 10 mg/kg, i.p. every day). Wistar rats were used for normotensive controls. Six weeks after nicorandil treatment, the bladder blood flow was estimated by hydrogen clearance method, and the bladder functions were estimated by voiding behavior studies and functional studies. Tissue levels of nerve growth factor (NGF) were measured by ELISA method. Furthermore, the participation levels of K(ATP) channel pores were investigated by real-time PCR. RESULTS: SHRs showed significant increases in blood pressure, micturition frequency, tissue levels of NGF and expressions of both K(IR) 6.1 and K(IR) 6.2 mRNAs, and a significant decrease in the bladder blood flow. The carbachol-induced contractile responses were similar in all groups. Although both doses of nicorandil failed to decrease the blood pressure, nicorandil significantly decreased the micturition frequency, tissue levels of NGF and increased the bladder blood flow in a dose dependent manner. The expressions of K(IR) 6.1 and K(IR) 6.2 mRNAs were slightly up-regulated by the low dose of nicorandil, whereas the high dose of nicorandil significantly up-regulated those expressions compared to non-treated SHRs. CONCLUSIONS: These data indicate that nicorandil prevents hypertension-related bladder dysfunction in the SHR, which may be related to its effect on the increased blood flow in the bladder.

Analysis of bladder vascular resistance before and after prostatic surgery in patients with lower urinary tract symptoms suggestive of benign prostatic obstruction.

AIMS: To evaluate bladder vascular resistance before and after transurethral resection of the prostate (TURP). METHODS: Thirty-three patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction were prospectively studied. We analyzed correlations of bladder vascular resistance with various factors including age, vascular risk factors, symptom score, prostate volume (PV), and urodynamic parameters before and 3 months after TURP. Using contrast-enhanced color Doppler ultrasonography for measuring bladder vascular resistance, resistive index (RI) of vesical arteries was calculated. RESULTS: Compared with healthy young male (n = 10) and age-matched controls (n = 10), the study patients had a higher preoperative RI (0.403 ± 0.100, 0.436 ± 0.042, and 0.561 ± 0.089, respectively; P < 0.01). Preoperative RI was significantly higher in patients with PV ≥ 60 ml versus <60 ml (0.604 ± 0.078 vs. 0.525 ± 0.082; P < 0.01), and in patients with severe obstruction versus mild/moderate obstruction (0.615 ± 0.087 vs. 0.534 ± 0.078; P = 0.017). Overall RI decreased significantly after TURP (from 0.561 ± 0.089 to 0.450 ± 0.086; P < 0.001). In patients with persistent urgency after TURP, RI was less improved than in those without urgency after TURP (change of RI 0.068 ± 0.098 vs. 0.135 ± 0.090; P < 0.05). This study was limited by a small sample size. CONCLUSIONS: Bladder vascular resistance in patients with LUTS was elevated in correlation with PV and severity of obstruction. Although bladder vascular resistance decreased significantly after TURP in overall patients, less reduction of vascular resistance was related to persistent urgency after TURP, implying that persistent urgency after TURP might be caused by persistent bladder ischemia.

Suppression of bladder overactivity and oxidative stress by the phytotherapeutic agent, Eviprostat, in a rat model of atherosclerosis-induced chronic bladder ischemia.

OBJECTIVES: To clarify the mechanism by which chronic bladder ischemia causes bladder functional changes, and to investigate the involvement of oxidative stress and pro-inflammatory cytokines, and the effects of the phytotherapeutic drug, Eviprostat, on these biochemical marker levels and bladder function. METHODS: Male Sprague-Dawley rats aged 15 weeks were divided into three groups. Arterial injury was experimentally induced by balloon endothelial injury of the iliac arteries, and a 2% cholesterol diet was given for 8 weeks. Rats in the arterial-injury group were given daily oral vehicle or Eviprostat, whereas sham-operated animals on a regular diet (0.09% cholesterol) were given vehicle for the last 2 weeks. Eight weeks after surgery, the levels of bladder pro-inflammatory cytokines, as well as bladder and urinary oxidative-stress markers, were determined. Cystometrograms were carried out without anesthesia or restraint. RESULTS: Bladder and urinary oxidative-stress markers, and bladder pro-inflammatory cytokine levels were significantly increased in the arterial-injury group, and Eviprostat markedly suppressed these increase. The cystometrograms showed that arterial injury decreased the intermicturition interval without affecting the micturition pressure. This decrease was reversed by Eviprostat treatment. CONCLUSIONS: Oxidative stress and pro-inflammatory cytokines might be involved in the development of overactive bladder by atherosclerosis-induced chronic bladder ischemia. Eviprostat might provide an attractive treatment option for individuals with bladder dysfunction due to chronic bladder ischemia because of its anti-oxidant and anti-inflammatory properties.

[Hyperbaric oxygenation in combined treatment of interstitial cystitis].

A total of 116 female patients with painful bladder syndrome/interstitial cystitis aged 32-78 years (mean age 56 +/- 2.4 years) entered the trial. They were divided into two groups according to treatment. Group 1 (n = 54) received 10-day combined conservative treatment consisting of antimicrobial drugs (if urinary infection was diagnosed), angioprotectors, mast cell activity stabilizers and bladder instillation with combined solution. Group 2 included 62 patients whose treatment included complex anti-inflammatory therapy in combination with HBO sessions (7-10 sessions in barochamber OKA-MT, 2.0 +/- 0.2 atm). Subjective (the disease course, pain intensity, 24-h and nocturnal pollakiuria, effective urine volume) and objective (microcirculation in the bladder wall) results were assessed. Dopplerograms revealed venous stagnation. Patients of group 2 had a persistent improvement of microcirculation in bladder mucosa as shown by better blood flow in the veins and arterioles. In group 1 the above improvement was less pronounced. Thus, HBO in combined treatment of interstitial cystitis improves treatment results and promotes long-term remission of the disease.

Angiogenesis as a therapeutic target in urothelial carcinoma.

In the last few years, angiogenesis has confirmed its critical role in the development of malignant neoplasms. Antiangiogenic drugs, mainly bevacizumab, sorafenib, or sunitinib, are currently approved in a wide number of tumor types, such as breast, colorectal, liver, or kidney cancer, and have changed dramatically the evolution of our patients. Unfortunately, in urothelial carcinoma, which is a very common neoplasm, antiangiogenic agents are still in a very preliminary phase of clinical research. In this study, we focus on the biological basis of angiogenesis in urothelial tumors, its influence in the prognosis of these malignancies, and the available evidence about the use of antiangiogenic drugs in urothelial carcinoma.

Involvement of nitric oxide in microcirculatory reactions after ischemia-reperfusion of the rat urinary bladder.

BACKGROUND: Nitric oxide (NO) plays a role in inflammation. Our aim was to investigate the role of NO in the microcirculatory changes after ischemia-reperfusion (I/R) of the bladder using intravital videomicroscopy (IVM). METHODS: In rats, 60 min of bladder ischemia followed by 30 min of reperfusion was performed in the presence of N(G)-nitro-L-arginine methyl ester (L-NAME), the NO precursor L-arginine, or saline pre-treatments. Venular red blood cell velocity (RBCV), functional capillary density (FCD), vessel diameters, and leukocyte-endothelial cell interactions in postcapillary venules were determined. Concentrations of nitrite/nitrate in the plasma and myeloperoxidase (MPO) levels in the lungs and the bladder were measured. RESULTS: Elevations of the numbers of rolling and adherent leukocytes, and of plasma nitrite/nitrate levels were found, while FCD and RBCV decreased. L-NAME pretreatment ameliorated the enhanced leukocyte-endothelial cell interactions without influencing the microcirculatory perfusion. In contrast, the L-arginine pretreatment further increased plasma nitrite/nitrate levels and preserved the FCD and RBCV, but did not affect leukocyte-endothelial interactions. None of these treatments influenced MPO activities. CONCLUSION: Our results suggest that NO plays an enhancing role in the I/R-induced neutrophil-endothelial interactions of the bladder. Supplementation of NO ameliorates the microcirculatory perfusion deficit without influencing the postischemic microcirculatory inflammatory reactions.

Kohki tea protects the rabbit bladder from ischemia/reperfusion-induced contractile dysfunction.

OBJECTIVES: Results of several studies indicated that ischemia/reperfusion is an etiological factor in obstructive bladder dysfunction. Kohki tea pretreatment was shown to reduce the dysfunctions induced by partial outlet obstruction in rabbits. The current study was designed to determine if pretreatment of rabbits with Kohki tea could prevent the contractile dysfunctions induced by bilateral ischemia followed by reperfusion. METHODS: New Zealand white rabbits were separated into several groups; one half of each group was pretreated by oral gavage for 3 weeks with Kohki tea and the other half was treated with vehicle (water). Experimental groups were subjected to bilateral ischemia for either 1 or 3 h followed by reperfusion for either 1 h or 1 week (4 groups). The results from the experimental groups were compared to the groups of rabbits receiving sham operations. RESULTS: Under all experimental conditions, Kohki tea significantly reduced the contractile dysfunctions induced by ischemia and ischemia followed by reperfusion. CONCLUSIONS: This data is consistent with the concept that Kohki tea acts by protecting the bladder smooth muscle and mucosa from cellular damage caused by ischemia/reperfusion.

Preventive effects of Ginkgo biloba extract on ischemia-reperfusion injury in rat bladder.

AIMS: The aim of this experimental study was to evaluate the effects of Ginkgo biloba (EGb 761) on ischemia-reperfusion (I-R) injury in the rat bladder. METHODS: A bladder I-R injury was induced by abdominal aorta occlusion by ischemia for 30 min, followed by 45 min reperfusion in rats. The rats were divided into four groups of 7 rats each; the control, I-R, and I-R groups were pretreated intraperitoneally with 50 or 100 mg/kg G. biloba 60 min before ischemia induction. Contractile responses to carbachol through isolated organ bath studies were recorded, histological sections were evaluated by light microscopy, and TUNEL staining was performed for the evaluation of apoptosis. RESULTS: In the I-R group, the contractile responses of the bladder strips were lower than those of the control group (p < 0.01-0.001) and were restored by pretreatment with 100 mg/kg G. biloba (p < 0.05-0.001). Decreased polymorphonuclear leukocyte infiltration was detected in the G. biloba pretreatment groups when compared to the I-R group during histological evaluation. The ratio of TUNEL-positive nuclei was 1.84% in the I-R group, whereas it was decreased in both of the G. biloba pretreatment groups (p < 0.01, p < 0.01). CONCLUSION: Our data indicated that G. biloba has a preventive effect on I-R injury in rat urinary bladder.