Effects of angiotensin Ⅱ on release of CRH and AVP from hypothalamus during acute hypoxia  

急性低氧条件下血管紧张素Ⅱ对下丘脑CRH和AVP分泌的作用<英文>

作　　者：吴雁[1] 杜继曾[1] 

机构地区：[1]浙江大学生命科学学院

出　　处：《Acta Pharmacologica Sinica》2000年第11期77-80,共4页中国药理学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China, No 39770288.

摘　　要：AIM: To investigate the effects of angiotensin Ⅱ(Ang Ⅱ) on corticotropin-releasing hormone (CRH) and argi-pressin (AVP) release from median eminence (ME) of hypothalamus during acute hypoxia in rats. METHODS: Simulated hypoxia was performed in a hypobaric chamber. CRH and AVP were determined by radioim-munoassay (RIA). Plasma corticosterone concentration was measured by fluorometry. RESULTS: Ang Ⅱ did not influence CRH release induced by hypoxia [CRH in group pretreated with Ang Ⅱ (16±8) ng/ME vs control (15±4) ng/ME, both exposed to hypoxia with simulated altitude 7 km (8.2 % O2)]. Ang Ⅱ enhanced AVP release, from (5.7±1.6) ng/ME in control decreasing to (2.6±1.2) ng/ME (P < 0.05), meanwhile plasma corticosterone concentration was also increased markedly, from (356±58) in control to (536±134) μg/L plasma (P < 0.05), which was partly abolished by administration of AVP antiserum. CONCLUSION: Ang Ⅱ might stimulate hypothalamo-pituitary-adrenal axis (HPA) through activating AVP but not CRH release during acute hypoxia.目的:研究低氧条件下血管紧张素Ⅱ对下丘脑促肾上腺皮质素释放素(CRH)和精氨酸加压素(AVP)分泌的作用.方法:低氧暴露采用人工模拟低压低氧.CRH和AVP的测定采用放射免疫测定法.血浆皮质酮测定采用荧光法.结果:7 km(8.2％O_2)急性低氧暴露1 h,AngⅡ不影响低氧引起的下丘脑CRH的分泌[低氧对照组:(15±4)ng/ME,低氧、脑室给Ang Ⅱ组:(160±8)ng/ME]但可增加下丘脑AVP的分泌[ME中AVP水平从低氧对照组(5.7±1.6)ng/ME下降到低氧、脑室给A Ⅱ组(2.6±1.2)ng/ME],同时血浆皮质酮水平也升高[从(356±58)μg/L plasma升高到(536±134)μg/L plasma],此作用可被AVP抗体部分反转.结论:急性低氧条件下,Ang Ⅱ对CRH的分泌无明显直接作用,它可能通过增加下丘脑AVP的分泌进而刺激下丘脑-垂体-肾上腺皮质轴的功能.

关 键 词：angiotensin II corticotropin-releasing honnone ARGIPRESSIN hypoxia 

分 类 号：R363[医药卫生—病理学]