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41.
It is generally accepted that the phospholipase-A2-cyclooxygenase-prostanoids-cascade mediates spinal sensitization and hyperalgesia. However, some observations are not in line with this hypothesis. The aim of the present work was to investigate whether different components of this cascade exhibit nociceptive or antinociceptive effects in the rat formalin test. Intrathecal (i.th.) injection of prostaglandin E2 (PGE2) induced a dose-dependent antinociceptive effect on the formalin-induced nociception. Furthermore, thimerosal, which inhibits the reacylation of arachidonic acid thereby enhancing arachidonic acid levels, had an antinociceptive effect rather than the expected pronociceptive effect when given i.th. While the phospholipase A2 inhibitor methyl arachidonyl fluorophosphonate (MAFP; i.th.) had a significant antinociceptive effect, its analogue palmitoyl trifluoromethyl ketone (PTFMK; i.th.) had no significant effect on the formalin-induced nociception. However, MAFP, but not PTFMK, showed a cannabinoid CB1 agonistic effect as shown by the inhibition of electrically evoked contractions of the vas deferens isolated from CB1 wild-type mice but not of that from CB1 knockout mice. The antinociceptive effect of MAFP was completely reversed by the CB1 receptor antagonist AM-251 (i.th.), thus attributing such effect to its CB1 agonistic effect. Moreover, the antinociceptive effect of the cyclooxygenase inhibitor, flurbiprofen (i.th.) was reversed by the co-administration of AM-251, but not by PGE2. Finally. the combination of phenylmethylsulfonyl fluoride (PMSF; intraperitoneal), which inhibits the degradation of anandamide through the inhibition of fatty acid amidohydrolase, with thimerosal (i.th.) produced a profound CB1-dependent antinociception. The present results show that endocannabinoids play a major role in mediating flurbiprofen-induced antinociception at the spinal level.  相似文献   
42.
腹股沟疝修补术致双侧输精管梗阻的临床研究   总被引:1,自引:0,他引:1  
目的:探查腹股沟疝修补术导致输精管梗阻的原因及输精管再通的可复性。方法:做患者双侧输精管造影确定梗阻部位,并对患侧行手术探查及通液。结果:输精管造影显示双侧输精管显影至耻骨联合上方两侧,探查术中可见右侧腹股沟管中段近睾端输精管断端,输精管远端消失;对左侧腹股沟管内环口处输精管局部狭窄的可疑梗阻部位进行穿刺,用6号平针头加压突破输精管狭窄梗阻部位,有明显突破感。然后行输精管注水通畅试验,再向睾丸方向输精管穿刺抽取精液化验可见成活精子。结论:输精管断离和手术钳夹输精管损伤,是腹股沟疝修补术导致输精管梗阻的两种原因,再通治疗困难。而采用针头穿刺疏通法时未放置导丝,易引发术后输精管管腔粘连导致再次梗阻。  相似文献   
43.
Alpha2-adrenoceptor antagonists, which can enhance synaptic norepinephrine levels by blocking feedback inhibition processes, are potentially useful in the treatment of disease states such as depression, memory impairment, impotence and sexual dysfunction. (10bS)-1,2,3,5,6,10b-Hexahydropyrrolo[2,1-a]isoquinoline oxalate (YSL-3S) was evaluated in several in vitro biological tests to establish its pharmacological profile of activities as an alpha2-adrenoceptor antagonist. Saturation binding assay revealed that [3H]rauwolscine bound to the alpha2-adrenoceptors with a Kd value of 6.3+/-0.5 nM and a Bmax value of 251+/-39 fmol/mg protein in rat cortical synaptic membranes. Competitive binding assay showed that YSL-3S inhibited the binding of [3H]rauwolscine (1 nM) in a concentration-dependent manner with a Ki value of 98.2+/-12.1 nM while it did not inhibit the binding of [3H]cytisine (1.25 nM) to neuronal nicotinic cholinergic receptors. The Ki values of yohimbine, clonidine and norepinephrine for [3H]rauwolscine binding were 15.8+/-1.0, 40.1+/-5.9 and 40.0+/-11.5 nM, respectively. In addition, the binding affinity of YSL-3S for alpha2-adrenoceptors was higher than that of its antipode and the racemic mixture. The functional activity of YSL-3S at the presynaptic alpha2-adrenoceptors was assessed using the prostatic portion of the rat vas deferens. Clonidine inhibited field-stimulated contractions of the vas deference in a dose-dependent manner. The presence of YSL-3S or yohimbine caused a parallel, rightward the dose-response curve of clonidine in a dose-dependent manner, indicating an antagonistic action at the presynaptic alpha2-adrenoceptors. The pA2 values of yohimbine and YSL-3S were 7.66+/-0.13 and 6.64+/-0.18, respectively. The results indicate that YSL-3S acts as a competitive antagonist at presynaptic alpha2-adrenoceptors with a potency approximately ten times lower than yohimbine, but is devoid of binding affinity for neuronal nicotinic cholinergic receptors.  相似文献   
44.
1 Antidepressant therapy is considered as one of the factors leading to male infertility. 2 In this study, the effects of long‐term treatment with fluoxetine or venlafaxine were investigated on electrical field stimulation (EFS, 1–64 Hz), noradrenaline (10?8 to 10?4 m ), serotonin (10?8 to 10?4 m ), adenosine 5′‐triphosphate [ATP (10?8 to 10?4 m )] and 80 mm KCl‐induced contractile responses in the epididymal and prostatic portions of rat isolated vas deferens strips. 3 Serotonin‐induced contractile responses were significantly increased in the epididymal portion of the vas deferens obtained from the fluoxetine‐treatment group, whereas in the prostatic portion there was no change. However, venlafaxine treatment had no effect on serotonin responses in the either portion of the vas deferens. Both fluoxetine and venlafaxine treatment significantly inhibited ATP‐evoked contractions of the prostatic and epididymal portions of the rat vas deferens, but had no effect on EFS, noradrenaline‐ and KCl‐evoked contractions of the vas deferentia in both portions. 4 In conclusion, these results suggest that chronic treatment with fluoxetine and venlafaxine affects vas deferens motility. Purinoceptors may, at least in part, responsible for the impaired motility in chronic treatment of venlafaxine and fluoxetine.  相似文献   
45.
电场刺激后释放的内源性去甲肾上腺素可引起大鼠输精管的双相收缩。初始的短暂收缩可被30μmol/L兰尼定和2μmol/L硝苯啶减弱,而后继的收缩部分可被2μmol/L硝苯啶消除,但被30μmol/L兰尼定增强。 外加的去甲肾上腺素也可产生输精管的双相收缩,这两相都能被2 μmol/L硝苯啶抑制,兰尼定30μmol/L可使两个相的收缩都减弱50%。我们推测兰尼定的结合位点在输精管的内质网。兰尼定对α-肾上腺素能刺激的不同相的作用不一致,表明对α-肾上腺素能的刺激一收缩偶合有两种方式。  相似文献   
46.
The immunophilin 12-kDa FK506 binding protein (FKBP12) stabilizes intracellular Ca2+ release channel (CRC) activity in different tissues. In this work, the presence of FKBP12 in rat vas deferens (RVD) and its possible contribution to RVD function was investigated. Treatment under appropriate pH, temperature, and ionic conditions was used to strip FKBP12 from CRC binding sites; Western blotting revealed FKBP12 in control but not in treated homogenates. Disruption of the FKBP12-CRC complex in RVD decreased the Ca2+ content of sarcoplasmic reticulum (SR) by increasing Ca2+ leakage through the ryanodine receptor (RyR3 isoform) but not through 1,4,5-iNOSitol trisphosphate receptors (IP3R1 and IP3R3 isoforms). The decrease of SR Ca2+ content was not related to inhibition of SERCA ATPase. It seems that dissociation of FKBP12-RyR leads to conformational changes in RyR that make it difficult for ryanodine to access its binding site. Rapamycin, which is commonly used as a pharmacological tool to disrupt the FKBP12-RyR complex, decreased phenylephrine-induced contractions in RVD epididymal halves. The data suggest that FKBP12 is expressed in RVD in a labile association with RyR3. Disruption of the FKBP12-RyR3 complex may lead to modifications of RVD physiology and in consequence may compromise male fertility.  相似文献   
47.
本文用免疫细胞化学PAP法,观察了大白鼠输精管神经肽(NPY)样免疫反应神经元。NPY样免疫反应神经元位于大白鼠输精管粘膜固有层内。免疫反应细胞体多为椭圆形,少数圆形。免疫反应产物呈颗粒状分布于细胞质中。讨论了NPY与去甲肾上腺素共存于大白鼠输精管组织中的去甲肾上腺素能神经元中及其相互生理作用。  相似文献   
48.
The synthesis of the hexapeptide [Glu6]SP6-11 and its glycosylated analogue at the Glu6γ-carboxyl position by solution procedures according to several strategies is discussed. The biological activity of SP, [GIu6]SP6-11 (VI) and [Glu(β-d -Glcp)6]SP6-11 (VIII) have been determined and compared to SP by the GPI and RVD assays. The introduction of a β-d -glucopyranosyl moiety at the sixth position of the [Glu6]SP6-11 did not affect to a great extent the in vitro activity pattern of the parent hexapeptide.  相似文献   
49.
聚丙烯补片在腹股沟疝修补术中对输精管的影响   总被引:3,自引:0,他引:3  
张凯  席时富 《实用医学杂志》2008,24(9):1574-1575
目的:探讨聚丙烯补片行腹股沟疝修补术对输精管的影响。方法:使用巴德公司生产SpomaTex补片进行疝修补,用来保护精索与输精管,并与同期单纯用聚丙烯平片行疝修补术的患者进行对比,观察二者对输精管的影响。结果:用SpomaTex补片与用普通补片行腹股沟疝修补的患者均未发现精索粘连及不育等并发症。结论:近期随访中,未发现精索粘连及不育等并发症,有待于长期各科合作的随访,国外已有聚丙烯补片引起不育的报道,应引起临床的高度重视。  相似文献   
50.
目的:探讨急性热应激对性成熟雄性小鼠睾丸、附睾、输精管中热休克蛋白70(heat shock protein 70,HSP70)表达的影响。方法:将32只8周龄雄性小白鼠随机均分为4组,饲养7d后,进行热应激处理,温度控制在(39±0.5)℃,时间分别为0.5、1和3h。应激后立即采血,分离血清测定谷草转氨酶(GOT)含量。一侧附睾制备精子悬液,用于计算精子密度和顶体畸形率;另一侧附睾、睾丸、输精管用于免疫组化研究。结果:应激后,小鼠体重、睾丸系数、顶体畸形率变化不显著(P>0.05),附睾系数和精子密度有不同程度的下降,GOT含量急剧升高(P<0.01)。随着应激时间的延长,小鼠精子密度呈递减趋势,顶体畸形率呈上升趋势。应激时间最短的0.5h组小鼠体重、睾丸系数、附睾系数的降幅反而最大。免疫组化法观察发现,HSP70在性成熟小鼠睾丸、附睾、输精管中均有表达。正常状态下,HSP70在睾丸组织间质细胞中少量表达,应激后分布于间质细胞核,此外在精母细胞核与精子细胞核中也有大量分布;附睾中HSP70主要分布于主细胞质,基细胞和亮细胞中没有表达,应激后附睾体的纤毛细胞中也发现大量棕色颗粒;输精管中HSP70主要定位在基细胞质,主细胞中不表达。随着应激时间的延长,HSP70在睾丸、附睾中的表达量明显升高,而在输精管中的增幅不明显。结论:急性热应激对性成熟雄性小鼠的生殖系统造成了损伤;HSP70在睾丸、附睾、输精管中的表达与定位具有区域特异性和细胞特异性,提示其可能参与精子的发生与成熟;HSP70在应激状态下表达量大幅上升的作用可能在于保护细胞免受高热损伤。  相似文献   
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