雌激素抑制去卵巢家兔实验性主动脉粥样硬化的形成

Inhibiting Effect of Estrogen on Experiemental Aortic Atherosclerosis in Ovariectomized Rabbits

为探讨雌激素对动脉粥样硬化的作用和机制，以不同剂量雌激素或联合应用孕激素来替代治疗去卵巢动脉粥样硬化家兔。分别于实验前、第4和14周末分别测定血清脂质、丙二醛和超氧化物歧化酶，实验第14周末测定血浆氧化型低密度脂蛋白、6－酮基－前列腺素F1α和血栓素B2浓度，并做病理形态学检查。结果发现，与对照组相比，激素替代治疗各组血清总胆固醇、甘油三酯、丙二醛、氧化型低密度脂蛋白及血栓素B2浓度显著降低（P＜0．01，P＜0．05）；而血浆6-酮基-前列腺素F1α浓度显著增高（P＜0．05）；激素替代治疗组主动脉斑块面积百分比平均减少了57．8％（P＜0．01）。孕激素对雌激素的作用无影响。以上提示雌激素能够抑制家兔主动脉粥样硬化形成，其机制可能与改善脂质作用，抑制过氧化形成和调节前列腺素代谢有关。

Aim To study the effect of estrogen(E)or estro-gen combined with progestogen(P)on atherogenesis and the mechanism in ovariectomized rabbits.Methods 40 ovarictomized rabbits were randomized into low E,low EP,high E,high EP and control groups.Each group was fed high cholesterol diet for 14 weeks.Group low E,low EP,high E,high EP were replaced different dose of estrogen or estrogen combined with progestogen.Before the experiment,at the end of the fourth or fourteenth week,the serum lipid,MDA and SOD were determined.At the end of the experiment,the plasma 6-keto-PGF1αTXB2 and ox-LDL levels were assayed.After killing the ani-mals,pathomorphological examination was carried out.Results Compared with the control group,the serum levels of total cholesterol(TC),triglyceride (TG),MDA and plasma ox-LDL,TXB2 concentra-tions were significantly lower(P<0.05~0.01)in the groups of the hormone replacement.While the plas-ma 6-Keto-PGF1αconcentrations were signicantly high-er(P<0.05).The plaque areas percent of the whole aortic intima surface areas in the therapy groups re duced by 57.8% averagely(P<0.01).Conclusion Estrogen could inhibit the aortic atherogenesis of the rabbits,its methanisms might be associated with serum lipid-lowing,inhibition of the lipidoxidation and regulation of the prostaglandin metabolism.Progestogen had no anti-atherosclerotic effect on ovariectomized rabbits.