【摘要】 目的本研究观察雄激素缺乏对大鼠肠系膜小动脉舒缩功能的影响,以及其是否涉及Rho/Rho激酶(ROCK)信号通路。方法用离体血管张力法检测24周龄对照和去势大鼠的肠系膜小动脉收缩和舒张反应。结果 1)去势组大鼠的肠系膜小动脉对苯肾上腺素(PE)收缩反应较对照组无差异;2)去势组与对照组比较对低浓度(0.01μM)的乙酰胆碱(ACh)、硝普钠(SNP)舒张反应增强(23%±5%vs.5%±3%,28%±7%vs.9%±3%,respectively,P<0.05),高度浓度时(10μM)无差别;3)预孵育ROCK抑制剂(Y-27632,1μM)后,较抑制前对照组对PE收缩反应降低(Emax99%±4%vs134%±8%,P<0.01),去势组未有改变;两组对ACh反应较抑制前均无差异,两组对浓度依赖的Y-27632舒张反应也无差异。结论去势不影响大鼠肠系膜小动脉的收缩功能,但减弱了其对ROCK的敏感性;去势可增强大鼠肠系膜动脉的内皮和非内皮依赖性舒张,与ROCK无关。更多还原

【Abstract】 Objective To investigate the effect of androgen deprivation on the reactivity of small mesenteric artery (SMA) in rats, and whetherthis effect is susceptible to the involvement of Rho/Rho-kinase (ROCK) signal pathway. Methods SMA segments were extracted from orchidectomized and control male Sprague-Dawley (SD) rats to measure phenylephrine (PE) -induced contraction, acetylcholine (ACh) -induced endotheliumdependent relaxation and sodium nitroprusside (SNP) -induced endothelium-independent relaxation in the absence and presence of ROCK inhibitor (Y-27632), respectively. Results 1) There was no difference between orchidectomized and control arteries in PE-induced contraction (Emax122%±8% vs. 134%±8%, P>0.05). 2) Relaxation to low concentrations (0.01μM) of ACh and SNP were significantly higher in orchidectomy arteriesthan in controls (23%±5% vs. 5%±3%, 28%±7% vs 9%±3%, respectively, P<0.05), but not in high concentrations. 3) ROCK inhibition (Y-27632,1μM) reduced the PE-induced contractions in SMA from control rats compared to vehicle (Emax 99%±4% vs. 134%±8%, P<0.01), but not in orchi-dectomy group. Y-27632 inhibition showed no effect on ACh-response in orchidectomy and control arteries campared to vehicle, and there was no difference in concentration-dependent relaxation to Y-27632 in SMA from the two rat groups. Conclusion Androgen deficiency exhibited no effect on ratSMA contraction, and decreased the sensitivity of vascular contraction to ROCK. In contrast, orchidectomy can increase both endothelium-dependentand independent relaxation, irrespective of ROCK inhibition.更多还原