雌激素对高胆固醇兔一氧化氮及内皮素生成的影响

The effect of estrogen on ntric oxide and endothelin-1 in rabbit with high cholesterolemia.

观察雌激素对去卵巢高胆固醇兔动物模型主动脉一氧化氮及血浆内皮素-1的影响,以阐明雌激素抗动脉粥样硬化的部分机理.将21只纯种新西兰雌兔随机分入3组(各7只):A组(去卵巢未补充激素兔),B组(去卵巢补充雌激素兔),C组(未切除卵巢兔),都给予1%胆固醇饮食,8周后取主动脉应用Greiss试剂测定不同浓度的乙酰胆碱作用下主动脉NO代谢物NO_2^-及血浆内皮素的量.10^(-5)乙酰胆碱作用下,B、C组主动脉NO_2^-产量明显低于A组P<0.05),B、C组兔主动脉反应性高,10^(-5)乙酰胆碱作用下NO_2^-产量明显高于同组无乙酰胆碱时NO_2^-产量,A组即使在10^(-5)乙酰胆碱作用下,NO_2^-无明显增高.A组内皮素明显高于B组(P<0.05)及C组(P<0.01).雌激素在整体水平促进NO产生,并抑制内皮素-1生成,可能为抑制动脉粥样硬化形成的重要机理.

Objective: We used oophorectomized New Zeland White rabbit to investigate that if estrogen could affect the production of nitric oxide (NO) of the aorta and endothelin-1. The purpose of this study is to clarify part of the mechanisms that estrogen against atherosclerosis. Methods : Twenty one female New Zeland White rabbits were assigned to 3 groups, groups A: oophorectomized (n = 7) ,group B: oophorectomized and had 17-β estradiol treatment (4mg/d) (n = 7) , group C: sham operation (n=7),each of the 21 rabbits was given high cholesterol (lg/d)diet,8 weeks later,we took the aortas for the analysis of NO2- by Gresis reaction and took the plasma for endothelin-1 analysis by RIA technique. Results: The production of NO of the aorta to 10-5M acetycholine increased significantly (P<0. 05) in estradiol treated group, compared with the oophoretomized group. The production of NO of the aorta to 10-5M acetycholine aiso increased significantly (P<0. 05) in the same aorta without exposure to acetycholine. These effects were not observed in the oophorectomized rabbits. The plasma endothelin-1 of the oophorectomized rabbits were signifcantly higher than that of the estradiol trea tedrabbits (P<0. 05) and the rabbits with sham operation (P<0. 01). Conclusion: 17-β estradiol could inhibit the production of endothelin-1 in vivo and it could enhance the production of NO of the aorta under acetycholine, however,the underlizing mechanisms were unknown.