NO、ET-1在低压缺氧时脑血流量调节中的作用

摘要

Objective The article was to investigate the roles of nitric oxide(NO)and enothelin-1(ET-1)in regula-tion of cerebral blood flow(CBF)during acute hypoxia.Methods Rats were divided into normoxic group(Control)and acute hypoxia(AH),CBF were measured by electromagnetic blood flowmeter,the changes of plasm NO2- ,ET-1 con-tents,brain NO2- ,ET-1 contents and NOS activity were observed.Results Acute hypoxia caused an increase in CBF, plasm NO2- ,ET-1 contents,brain NO2- 、ET-1 contents and NOS activity,the ratio of ET-1/ NO2- in the brain were decreased,as compared with the control group.Conclusion NO and ET-1 may be involved in the regulation of CBF in acute hypoxia,but the NO-dependent vasodilation was stronger than the ET-1-dependent vasoconstriction.%目的：本文主要探讨急性低压缺氧时 NO 和 ET-1对脑血流量变化的调节作用。方法大鼠随机分为平原组和急性低压缺氧组，用电磁血流量计测定脑血流量，用 Gess 法和放免法分别测量血浆和脑 NO2－、ET-1含量，用双波长分光光度法测量 NOS 活性。结果急性低压缺氧时脑血流量、脑含水量、血浆和脑组织 NO2－、ET-1含量、NOS 活性明显增高（P ＜0．05），脑 ET-1／NO2－比值明显下降（P ＜0．05）。结论急性低压缺氧时，脑血流量增加， ET-1、NO 均参与了脑血流量变化的调节，NO 血管舒张作用大于 ET-1收缩作用。