CCNE1、RIP2基因多态性与膀胱癌发病风险的关系

目的 细胞周期蛋白 E1 （CCNE1） 基因和受体相互作用蛋白 2 （RIP2） 基因区域分别存在多态性位点 rs8102137 和 rs42490, 探讨这 2 种多态性与膀胱癌的发病风险及膀胱癌的病理分级和分期之间的关系。方法 收集膀胱癌患者 （膀胱癌组） 176 例及非肿瘤体检患者 （对照组） 210 例血样本并提取 DNA, 聚合酶链反应 （PCR） 测序方法检测 CCNE1 （rs8102137） 和 RIP2 （rs42490） 的多态性。根据术后病理结果确定膀胱癌患者的分级及分期。分析膀胱癌组和对照组中等位基因和基因型的分布差异。对 2 组间基因型的分布情况进行比较, 分析 CCNE1 （rs8102137） 和 RIP2 （rs42490） 各基因型与膀胱癌患者的临床资料间的关系, 及与膀胱癌遗传易感性的关系。结果 对照组样本的基因型分布具有良好的群体代表性。CCNE1 （rs8102137） 突变型 （C/T+C/C） 在膀胱癌组中频率 （40.91%） 高于对照组（30.95%, OR=1.54, 95%CI： 1.02～2.45, P＜0.05）。RIP2 （rs42490） 突变型 （A/G+G/G） 在膀胱癌组频率 （72.73%） 高于对照组 （62.38%, OR=1.61, 95%CI： 1.04～2.48, P＜0.05）。不同膀胱癌病理分级、 分期患者的 CCNE1 （rs8102137） 和 RIP2 （rs42490） 基因多态性差异无统计学意义。结论 CCNE1 （rs8102137）、 RIP2 （rs42490） 基因型与膀胱癌易感性关系密切, 携带突变型等位基因的个体患膀胱癌的风险显著高于野生型个体。     

S6K1和4EBP-1蛋白在膀胱尿路上皮癌中的表达及意义

目的探讨S6K1和4EBP-1蛋白在膀胱尿路上皮癌中的表达及意义。方法使用免疫印迹法(Western-blot)检测S6K1和4EBP-1蛋白在80例膀胱尿路上皮癌及20例正常膀胱黏膜中的表达。结果膀胱尿路上皮癌中S6K1蛋白表达率(64%)高于正常膀胱黏膜(10%),4EBP-1蛋白表达率(71%)高于正常膀胱黏膜(15%)。S6K1和4EBP-1蛋白在低分级膀胱癌中的表达率显著高于高分级膀胱癌中的表达率。复发肿瘤的S6K1和4EBP-1蛋白表达率高于初发肿瘤。而S6K1和4EBP-1蛋白表达率在不同性别患者、不同肿瘤分期和是否吸烟患者中差异无统计学意义。结论膀胱尿路上皮癌中S6K1和4EBP-1蛋白与膀胱癌的分级和复发相关,可能成为肿瘤诊断治疗的新靶点。     

Role of peripheral 5-HT1A receptors in detrusor over activity associated with partial bladder outlet obstruction in female rats

We have investigated the role of peripheral 5-hydroxytryptamine 1A (5-HT(1A)) receptors and their probable up-regulation in rat model of partial bladder outlet obstruction. Bladder outlet obstruction was induced in adult female rats, hypertropic bladders were harvested after 6 weeks and isometric contractions of bladder strips were recorded. A marked spontaneous activity of the bladder was observed in obstructed bladder strips compared to control strips. The effect of alpha(1A/1D)-adrenergic antagonist, tamsulosin, was observed to be inhibitory on the spontaneous contractions albeit at higher doses (10, 30 and 100 nM). As tamsulosin at higher doses also has high affinity for 5-HT(1A) receptors, the role of peripheral 5-HT(1A) receptors in overactive bladder was hypothesized. 8-hydroxy-2-(di-n-propylamino) tetralin [8-OH-DPAT], a selective 5-HT(1A) receptor agonist, dose-dependently induced significant contractions in the obstructed bladder strips, compared to control bladders. N-[2-[4-(2-methoxyphenyl) piperazin-1-yl]ethyl]-N-pyridin-2-yl-cyclohexanecarboxamide dihydrochloride (WAY-100635), a selective 5-HT(1A) receptor antagonist, competitively antagonized the contractile response to 8-OH-DPAT in obstructed bladder strips in a dose-dependent manner. Tamsulosin at a higher dose was also observed to antagonize the responses to 8-OH-DPAT. Taken together, these observations suggest the involvement of peripheral 5-HT(1A) receptors in detrusor over activity associated with bladder outlet obstruction in female rats.     

Effect of diltiazem on in vitro rabbit bladder function

The relationship between extracellular calcium and urinary bladder function was investigated by studying the effect of the specific calcium antagonist diltiazem on the functional ability of the in vitro whole rabbit urinary bladder to empty in response to pharmacological stimulation. The bladder was found to require an extracellular calcium concentration of 4.5 X 10(-4) M to elicit near complete cholinergic-mediated emptying. Diltiazem (1 X 10(-6) - 1 X 10(-4) M) inhibition of bladder function was competitively antagonized by increasing the extracellular calcium concentration (0.45 X 10(-4) - 3.6 X 10(-4) M). In the absence of diltiazem, alterations in the extracellular calcium concentration between 0.45 X 10(-4) and 3.6 X 10(-4) M had no significant effects on bladder response to bethanechol. KCl-mediated bladder emptying was significantly more sensitive to diltiazem inhibition than was bethanechol-stimulated emptying. Even at the intermediate diltiazem concentration of 1 X 10(-5) M, increasing the extracellular calcium concentration did not completely reverse the inhibitory effect of diltiazem on bladder response to KC1. These findings are consistent with the hypothesis that diltiazem at low concentrations may inhibit extracellular calcium influx while at higher concentrations translocation of intracellular stores of calcium may be inhibited as well. The study also suggests that diltiazem is capable of inhibiting urinary bladder function and deserves further consideration as a possible therapeutic agent in certain forms of urinary bladder dysfunction.     

Rabbit versus rat urinary bladder: effects of in vitro hypoxia.

PURPOSE: Studies indicate that bladder hypoxia may be an etiological factor for lower urinary tract dysfunction. Rat and rabbit are two species of experimental animals used frequently to study lower urinary tract function and dysfunction. The objective of this study was to compare directly effects of in vitro hypoxia on contractile responses of rat and rabbit urinary bladder to different forms of stimulation. METHODS: Sexually mature male New Zealand White rabbits and Sprague-Dawley rats were compared. Each bladder was excised while the animal was anesthetized, and longitudinal bladder strips were cut, then mounted in organ baths. A tension of 2 g was placed on all strips. Effects of 1, 2, 3 and 4 h hypoxia followed by 1 h of reoxygenation on contractile responses of bladder strips to field stimulation (FS), carbachol (100 micromol/l), ATP (1 mmol/l) and KCl (120 mmol/l) were determined. RESULTS: Contractility, per unit tissue mass, of rat bladder strips was significantly greater than that of rabbit bladder strips in response to FS (all frequencies), carbachol, KCl and ATP. Hypoxia (followed by reoxygenation) resulted in time-dependent progressive reduction in contractile responses of bladder strips to all stimuli. Rat bladder was significantly more sensitive to hypoxia than rabbit bladder in response to FS and carbachol. Hypoxia induced similar effects on rat and rabbit bladder responses to ATP and KCl. CONCLUSION: Rat bladder neurogenic and cholinergic responses are significantly more sensitive to hypoxia than are those of rabbit bladder, which may be due to the rat bladder's greater contractile force generation and previously reported higher Ca2+-ATPase activity.     

The influence of polymorphisms of glutathione S-transferases M1 and M3 on the development of human urothelial cancer

Cigarette smoking is the most important risk factor for development of transitional cell carcinoma of the urinary bladder. The effect of polymorphisms of glutathione S-transferases M1 (GSTM1) and M3 (GSTM3) on the influence of cigarette smoking on urinary bladder carcinogenesis was investigated. In total, 293 bladder cancer patients from hospitals in Dortmund and Wittenberg as well as 176 patients without any malignancy from a Department of Surgery from Dortmund were genotyped for GSTM1 and GSTM3 according to standard PCR/RFLP methods. Smoking habits were quantified by a standardized interview. The proportion of GSTM1 negative cases was 63% in the entire bladder cancer cases group compared to 50% in controls. The GSTM3*A/*A genotype was 76% in cancer cases versus 74% in controls. Smokers and ex-smokers were overrepresented in bladder cancer cases. A significant association between smoking status and GSTM1 or GSTM3 genotype was not detected. The elevated proportion of GSTM1 negative bladder cancer cases shows an effect of this polymorphic enzyme on development of bladder cancer. In contrast to other studies, an influence of GSTM1 on the risk due to cigarette smoking was not observed.     

Polymorphisms of xenobiotic metabolizing enzymes in bladder cancer patients of the Semmelweis University Budapest,Hungary

ABSTRACT

Polymorphic xenobiotic metabolizing enzymes such as N-acetyltransferase 2 (NAT2) or glutathione S-transferase M1 (GSTM1) are known to modulate bladder cancer risk. As no apparent data were available from Hungary, a former member of the eastern European economic organization, a study was performed in Budapest. In total, 182 bladder cancer cases and 78 cancer-free controls were investigated by questionnaire. Genotypes of NAT2, GSTM1, GSTT1, rs1058396 and rs17674580 were determined by standard methods. Current smokers’ crude odds ratio (OR) (3.43) and former smokers crude OR (2.36) displayed a significantly increased bladder cancer risk. The risk rose by a factor of 1.56 per 10 pack years. Exposure to fumes was associated with an elevated bladder cancer risk (23% cases, 13% controls). Sixty-four % of the cases and 59% of controls were slow NAT2 acetylators. It was not possible to establish a particular impact of NAT2*6A and *7B genotypes (15 cases, 8%, 5 controls, 7%). GSTT1 exerted no marked influence on bladder cancer (negative 21% cases vs. 22% controls). The portion of GSTM1 negative bladder cancer patients was increased (63% cases vs. 54% controls). The SLC14A1 SNPs rs1058396[AG/GG] and the nearby rs17674580[CT/TT] occurred more frequently in cases (79% and 68%) than controls (77% and 55%). The portion of GSTM1 negative bladder cancer patients is comparable with portions reported from other industrialized areas like Lutherstadt Wittenberg/Germany (58%), Dortmund/Germany (70%), Brescia/Italy (66%) or an occupational case-control series in Germany (56%). Data indicate that GSTM1 is a susceptibility factor for environmentally triggered bladder cancer rather than for smoking-mediated bladder cancer.     

Effect of dexamethasone on cyclophosphamide-induced cystitis in rats: lack of relation with bradykinin B1 receptor-mediated motor responses

We investigated the role of bradykinin B receptors in inducing urinary bladder contraction and maintaining bladder compliance in anaesthetized rats following cyclophosphamide-induced bladder inflammation and the influence of dexamethasone treatment on these responses. In the group treated with cyclophosphamide the amplitude of the contraction induced by the selective bradykinin B1 receptor agonist des-Arg9-bradykinin was larger than that in controls and dexamethasone prevented the up-regulation of this response induced by inflammation. The specific binding of [3H]des-Arg10-kallidin to bladder membranes was only detected in cyclophosphamide-treated rats: this binding was prevented by dexamethasone pretreatment. The bladder contraction induced by des-Arg9-bradykinin in cyclophosphamide-treated rats was antagonized by the bradykinin B1 receptor antagonist des-Arg9-D-Arg-[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (des-Arg10-Hoe 140). Cyclophosphamide treatment increased the bladder weight and dexamethasone reversed this effect. Bladder compliance was decreased in the bladder inflammation group and this effect was partially reversed by dexamethasone pretreatment. Neither des-Arg10-Hoe 140 nor the combined administration of des-Arg10Hoe 140 and the selective bradykinin B2 receptor antagonist D-Arg-[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (Hoe 140) affected bladder compliance, thus excluding a role of kinins in the maintenance of bladder tone during inflammation. These results indicate that: (1) dexamethasone pretreatment ameliorates cyclophosphamide-induced bladder inflammation: (2) dexamethasone pretreatment prevents cyclophosphamide-induced up-regulation of bradykinin B receptors; (3) kinins do not contribute to the increased vesical tone during inflammation.     

Tretinoin or retinol enhancement of lymphokine-activated killer cell proliferation and cytotoxicity against human bladder cancer cells in vitro.

AIM: To study the effect of tretinoin (Tre) or retinol (Ret) on the proliferation of lymphokine-activated killer (LAK) cells in patients with transitional cell cancer of bladder and their cytolysis to bladder tumor cells. METHODS: LAK cell proliferation was assayed in the presence of either Tre or Ret by cell counting. Human transitional bladder cancer cell lines BIU-87, EJ, or bladder tumor cells (BTC) from patients with bladder cancer were used as target cells and cytotoxicity of LAK cells was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS: The proliferation of LAK cells induced by interleukin-2 (IL-2) was stimulated by Tre or Ret (10-100 nmol.L-1). The cytotoxicity of LAK cells against BIU-87, EJ cells, or BTC was enhanced by pretreatment of LAK cells with Tre or Ret 10-100 nmol.L-1. CONCLUSION: Tre or Ret enhances the proliferation and cytotoxicity of LAK cells from patients with bladder cancer. Retinoids are potential in adoptive immunotherapy of bladder cancer.     

膀胱癌组织中hnRNP K及Hugl-1的表达及临床意义

目的研究hnRNP K及Hugl-1的表达与人膀胱移行细胞癌（transitional cell carcinom a of bladder,TCCB）的临床病理的关系,探讨hnRNP K及Hugl-1与TCCB细胞发生、侵袭的相关性。方法对68例TCCB标本和38例前列腺增生症患者的膀胱壁应用单克隆抗体、免疫组化SP法检测hnRNP K及Hugl-1蛋白表达情况。结果TCCB组织中Hugl-1表达水平显著低于正常膀胱组织（P〈0.05）;而hnRNP K表达水平显著高于正常膀胱组织（P〈0.05）。TCCB组织中Hugl-1表达降低及hnRNP K表达增高与肿瘤分期、病理分级存在相关性（P〈0.05）,且TCCB组织中Hugl-1表达水平降低与肿瘤转移存在相关性（P〈0.05）。结论膀胱癌组织中Hugl-1表达下降及hnRNP K表达水平增高与TCCB的发生、发展过程有关。     

Urinary bladder cancer risk factors in an area of former coal,iron, and steel industries in Germany

ABSTRACT

This study was performed to investigate the frequency of bladder cancer in patients with an occupational history such as underground hard coal mining and/or painting after the structural change in the local industry. A total of 206 patients with bladder cancer and 207 controls were enlisted regarding occupational and nonoccupational bladder cancer risk factors by questionnaire. The phase II enzymes N-acetyltransferase 2 (NAT2), glutathione S-transferases M1 (GSTM1), and T1 (GSTT1) and the single nucleotide polymorphism (SNP) rs11892031[A/C] reported to be associated with bladder cancer in genome-wide association studies were genotyped. The bladder cancer risk in varnishers and underground hard coal miners was increased as previously shown in a study in this area performed in the 1980s. The occupation of a car mechanic was associated with a significantly elevated bladder cancer risk and higher in the case of underground hard coal miners even though the mine was closed in 1987. The frequency of GSTM1 negative genotype was comparable in cases and controls (53% versus 54%). In the case of NAT2, the slow NAT2 genotype was more frequent (62% versus 58%) and ultra-slow NAT2 genotype (NAT2*6A and/or *7B alleles only) was 23% versus 15%. An occupational history of a varnisher or an underground hard coal miner remains a risk factor for bladder cancer occurrence. Data indicate that in the case of bladder cancer, GSTM1 is a susceptibility factor related to environmental and/or occupational exposure.     

Coptisine inhibits the malignancy of bladder carcinoma cells and regulates XPO1 expression

This work is performed to investigate the effect of coptisine (COP) on the malignant biological behaviors of bladder carcinoma cells and its underlying mechanism. Bladder carcinoma cell lines were treated with different concentrations of COP in vitro. Cell counting kit-8 (CCK-8), scratch healing assay, Transwell assay, and flow cytometry were used to detect cell growth, migration, invasion, and cell cycle progression. Bioinformatics analysis was performed to predict the molecular targets of COP. Quantitative real-time PCR and western blot were adopted to determine the expression levels of exportin 1 (XPO1) mRNA and protein, respectively. Gene set enrichment analysis was applied to predict the signaling pathways related to XPO1. This study showed that COP treatment markedly suppressed the malignant biological behaviors of bladder carcinoma cells. XPO1 was identified as a downstream molecular target of COP in bladder carcinoma, and COP treatment inhibited the expression of XPO1 in bladder carcinoma cell lines. Overexpression of XPO1 reversed the impacts of COP on the malignant biological behaviors of bladder carcinoma cells. COP treatment modulated the expression level of cyclin D1 and CYP450 via XPO1. In summary, COP represses the malignant biological behaviors of bladder carcinoma cells and regulates XPO1 expression, which is promising to be a complementary drug for bladder carcinoma treatment.     

In vivo effects of drugs that act on the autonomic nervous system on the rat urinary bladder contraction accompanying micturition

We prepared an experimental system to study the effects of drugs on urinary bladder contraction and micturition simultaneously in rats anesthetized with urethane (1 g/kg, s.c.) and alpha-chloralose (25 mg/kg, s.c.). When Tyrode's solution was infused at a constant rate (0.8-1 ml/10 min) through a needle inserted into the bladder from the left ureter, the bladder pressure gradually and then steeply rose, and micturition took place. These changes in bladder pressure and micturition were constantly repeated. In this model, drugs which partially inhibited the bladder contractile force, e.g., atropine (0.01-1 mg/kg, i.v.) and hexamethonium (C6, 5 mg/kg, i.v.) increased the frequency of bladder contraction instead of decreasing the amount of solution excreted from the penis by bladder contraction. The rate of afferent discharges during bladder filling was increased after injection of atropine or C6, and this increase was considered to be responsible for the induction of the increase in the frequency of bladder contraction. Drugs which inhibited the bladder contraction and interrupted micturition, e.g., C6 (20 mg/kg, i.v.) raised the bladder pressure until the solution leaked from the penis. As phentolamine (5 mg/kg, i.v.) or propranolol (1 mg/kg, i.v.) did not facilitate bladder motility but rather inhibited it, the inhibitory action of sympathetic nerves on bladder motility was considered to be weak in rats. This model was useful for studying the effect of drugs on bladder motility and micturition reflex.     

Comparative study of the contractile activity evoked by ATP and diadenosine tetraphosphate in isolated rat urinary bladder.

The present study was designed to investigate the effect and possible mechanism(s) of action of ATP and diadenosine tetraphosphate (AP(4)A) on the isolated rat urinary bladder rings. ATP ( 0.1- 1 x 10(-3)M) or AP(4)A ( 0.01- 0.1 x 10(-3)M) produced contractions of the isolated bladder rings in a concentration-dependent manner. The contraction-induced by AP(4)A in the bladder rings was approximately ten times more potent than that produced by ATP. Addition of ATP prior to addition of AP(4)A or vice versa desensitized bladder tissue to the second agonist with great reduction in the contraction produced. Electrical field stimulation (EFS, 40 V, 0.5 ms, 2 Hz) produced contraction (79.8 +/-7.1 g tension x g(-1)tissue) in the bladder rings that can be greatly reduced by prior addition of ATP or AP(4)A. Theophylline, a P(1)-purinoceptor antagonist, significantly reduced the contraction-induced by AP(4)A and did altered that produced by ATP in bladder rings. Atropine, a non-selective muscarinic receptor antagonist, or indomethacin, a cyclo-oxygenase inhibitor, significantly suppressed the contractions of the bladder rings to ATP or AP(4)A. Similarly, nifedipine, an l -type Ca(2+)channel blocker, significantly attenuate the contractions induced by ATP and AP(4)A in the isolated rat urinary bladder rings. In conclusion, the results of the present study show that ATP, AP(4)A, and EFS evoked contractions in the rat urinary bladder rings and that the contractions induced by AP(4)A was more potent than that produced by ATP. Furthermore, the contractions evoked by ATP or AP(4)A were Ca(2+)-dependent and mediated at least in part through one of the cyclo-oxygenase products. Also, the present results suggested the involvement of the P(1)-purinoceptor in mediating the contractions evoked by AP(4)A but not ATP in the bladder rings.     

早期生长反应因子-1及乙酰肝素霉在膀胱移行细胞癌中的表达及意义

目的：探讨早期生长反应蛋白Egr-1在膀胱移行细胞癌中的表达和意义以及与乙酰肝素酶heparanase的相关性。方法：采用免疫组织化学SABC（StreptAvidin-Biotin Complex）法对58例膀胱移行细胞癌组织及10例正常膀胱粘膜组织进行Egr-1、heparanase的检测,并对两者表达情况与BTCC临床病理特征的关系,两者在BTCC中表达的相关性进行了统计分析。结果：Egr-1蛋白在10例正常膀胱组织中不表达,而58例BTCC组织中阳性表达占70.69%(41/58),差异有显著意义(P<0.01); heparanase蛋白在10例正常膀胱组织中不表达,而在58例BTCC组织中阳性表达占58.62%(34/58),差异有显著意义(P<0.01); Egr-1及heparanase阳性表达率在不同年龄、性别、肿瘤大小及数目的患者之间,无显著性差异（P>0.05);随着病理分级及临床分期增加,Egr-1及heparanase蛋白表达率及表达强度均增加。在BTCC中Egr-1蛋白与heparanase表达呈正相关(r =0.3875,P<0?01)。结论: Egr-1及heparanase蛋白的高表达在膀胱移形细胞癌的发生、发展中起重要作用,与非肌层浸润型膀胱癌进展为肌层浸润型膀胱癌过程相关。Egr-1可作为判断膀胱移形细胞癌生物学行为的重要指标,并且对临床开展肿瘤防治新途径提供理论依据。     

Occupational bladder cancer: Polymorphisms of xenobiotic metabolizing enzymes,exposures, and prognosis

ABSTRACT

Approximately 7% of all bladder cancer cases in males are associated with occupation. The question arises whether the use of genome-wide association studies was able to identify bladder cancer risk factors that may modulate occupational bladder cancer risk and prognosis. One hundred and forty-three bladder cancer cases with suspected occupational bladder cancer and 337 controls were genotyped for the following polymorphisms: N-acetyltransferase 2 (NAT2), glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), UDP-glucuronyltransferase 1A rs11892031 (UGT1A), rs9642880 (close to c-MYC), and rs710521 (close to TP63). The most relevant polymorphisms for occupational bladder cancer risk were GSTM1 and UGT1A, especially when co-occurring (GSTM1 negative and rs11892031[A/A]: 48% cases vs. 38% controls, OR 1.47, 95% CI 0.99–2.20). The effect was more pronounced in smokers. GSTM1 negative genotype occurred more frequently in cancer cases exposed to aromatic amines, carbolineum, and in painters and varnishers. UGT1A (rs11892031[A/A]) was found frequently in cases exposed to carbolineum, crack test spray, PAH, and in painters and varnishers. All investigated polymorphisms except rs710521 (TP63) seemed to exert an impact on recurrence risk. Relapse-free times were shorter for NAT2 slow and ultra-slow, GSTT1 positive and GSTM1 negative cases. Occupational bladder cancer cases with a number of risk variants displayed significantly shorter relapse-free times compared to cases with few, less relevant risk alleles as evidenced by median difference 8 months. In conclusion, in the present, suspected occupational bladder cancer cases phase II polymorphisms involved in bladder carcinogen metabolism modulate bladder cancer recurrence. Most relevant for bladder cancer risk were GSTM1 and UGT1A but not NAT2.     

Stimulation of bladder activity by volume, L-dopa and capsaicin in normal conscious rats - effects of spinal α1-adrenoceptor blockade

To study possible differences in α₁-adrenoceptor involvement in the spinal mechanisms mediating bladder activity induced by volume (bladder filling), central (L-dopa), and peripheral (capsaicin) stimulation, we investigated if these types of bladder activity were modified by intrathecal (i.t.) or intra-arterial (i.a.) administration of the α₁-adrenoceptor antagonist, indoramin. Indoramin is selective for the α_1A-adrenoceptor subtype, whereas most clinically used α₁-adrenoceptor antagonists, including doxazosin, have no subtype selectivity. The drug effects were studied by continuous cystometry in normal, conscious rats and rats with bladder activity evoked by intraperitoneal L-dopa (50 mg/kg after carbidopa pretreatment), or by intravesical capsaicin (30 μM). I.t. indoramin (50 nmol) significantly decreased micturition pressure, and increased bladder capacity and micturition volume. Dribbling incontinence due to urinary retention was observed in one of ten rats. L-dopa-stimulated bladder overactivity was significantly attenuated by i.t. or i.a. indoramin (50 nmol). Similar effects of i.t. and i.a. doxazosin (50 nmol) have been reported previously. Intravesical capsaicin (30 μM) caused bladder activity, which was attenuated by i.t. indoramin (50 nmol), but not by i.t. doxazosin (50 nmol). I.a. indoramin did not reduce capsaicin-induced bladder activity; doxazosin was moderately effective. The results suggest that the bulbospinal micturition reflex evoked by bladder filling and L-dopa involves a descending pathway where transmission is partly mediated by spinal α₁-adrenoceptors. Bladder overactivity evoked by intravesical capsaicin, which elicits a vesico-spinal-vesical reflex, was not affected by i.t. doxazosin in a dose that attenuates activity mediated through the bulbo-spinal pathway. This suggests less involvement of spinal α₁-adrenoceptors in the vesico-spinal-vesical than in the bulbo-spinal voiding reflex. Received: 29 November 1996 / Accepted: 3 March 1997     

Role of CXCR2 and TRPV1 in functional,inflammatory and behavioural changes in the rat model of cyclophosphamide-induced haemorrhagic cystitis

Background and Purpose: Cyclophosphamide induces urotoxicity characterized by the development of cystitis, which involves bladder overactivity and inflammation. Here, we investigated the roles of chemokine receptor 2 (CXCR2) and transient receptor potential vanilloid 1 (TRPV1) channels in a rat model of cyclophosphamide-induced cystitis.Experimental Approach: Cystitis induced by cyclophosphamide in rats was assessed by gross morphology, histology and immunohistochemistry of bladder tissue. mRNA for CXCR2 and TRPV1 channels were measured by RT-PCR. Nociceptive responses in paw and abdomen, along with cystometric measures were recorded.Key Results: Cyclophosphamide, i.p., induced pain behaviour, bladder inflammation and voiding dysfunction. The CXCR2 antagonist, SB225002, the TRPV1 channel antagonist, SB366791 or their combination reduced the mechanical hypersensitivity of paw and abdominal area and nociceptive behaviour after cyclophosphamide. Cyclophosphamide-induced cystitis was characterized by haemorrhage, oedema, neutrophil infiltration and other inflammatory changes, which were markedly decreased by the antagonists. Up-regulation of CXCR2 and TRPV1 mRNA in the bladder after cyclophosphamide was inhibited by SB225002, SB366791 or their combination. Expression of CXCR2 and TRPV1 channels was increased in the urothelium after cyclophosphamide. Bladder dysfunction was shown by increased number of non-voiding contractions (NVCs) and bladder pressures and a reduction in bladder capacity (BC), voided volume (VV) and voiding efficiency (VE). SB225002 or its combination with SB366791 reduced bladder pressures, whereas SB225002, SB366791 or their combination increased BC, VV and VE, and also reduced the number of NVCs.Conclusions and Implications: CXCR2 and TRPV1 channels play important roles in cyclophosphamide-induced cystitis in rats and could provide potential therapeutic targets for cystitis.     

Effects of cannabinoid receptor agonists on neuronally-evoked contractions of urinary bladder tissues isolated from rat, mouse, pig, dog, monkey and human

This study investigated the cannabinoid receptor, known to inhibit neuronally-evoked contractions of the mouse isolated urinary bladder, in bladder sections isolated from mouse, rat, dog, pig non-human primate or human. The CB(1)-like pharmacology of the cannabinoid receptor in mouse isolated bladder observed previously was confirmed in this study by the rank order of agonist potencies: CP 55940>/=WIN 55212-2>HU 210>JWH 015>anandamide, the high affinity of the CB(1) selective antagonist, SR 141716A (apparent pK(B) 8.7), and the low affinity of the CB(2) antagonist, SR 144528 (apparent pK(B)<6.5). In these studies, SR 141716A (10-100 nM) significantly potentiated electrically-evoked contractions in this tissue by an undetermined mechanism. A similar rank order of agonist potencies was determined in rat isolated bladder sections (CP 55, 940> or =WIN 55212-2>JWH 015). In this tissue, the maximal inhibitory effect of all agonists was lower than in the mouse bladder. Indeed, the effects of both HU 210 and anandamide were too modest to quantify potency accurately. In the rat isolated bladder, SR 141716A (30 nM) or SR 144528 (100 nM), reversed the inhibitory effect of WIN 55212-2 (apparent pK(B) = 8.4 and 8.0, respectively) or JWH 015 (apparent pK(B) = 8.2 and 7.4, respectively). These findings may demonstrate pharmacological differences between the rat and mouse orthologues of the CB(1) receptor. Alternatively, they may be attributed to a mixed population of CB(1) and CB(2) receptors that jointly influence neurogenic contraction of the rat bladder, but cannot be differentiated without more selective ligands. WIN 55212-2 had no effect on electrically-evoked contractions of bladder sections isolated from dog, pig, cynomolgus monkey and human. These findings suggest that the effect of cannabinoid agonists to inhibit neurogenic contraction of the mouse and rat bladder is not conserved across all mammalian species.