雌激素替代治疗对大鼠动脉粥样硬化的影响

Effect of estrogen replacement therapy in the early phase on atherosclerosis in rats

目的:了解早期经皮雌激素替代治疗(estrogen replacement therapy,ERT)对高脂喂养的去势雌性大鼠动脉粥样硬化水平的影响。方法:28只大鼠随机分为4组:A组为假手术对照组,B组为单纯去势组,C组为去势+小剂量ERT组,D组为去势+大剂量ERT组。4组小鼠均给予高脂饮食12周,分别于术前、高脂喂食4周和12周后抽血测定血脂、雌二醇含量及血清SOD活力。结果:12周后B组小鼠血清雌二醇含量明显低于A组(P<0.05),D组明显高于A组(P<0.05),C组与A组间比较差异无统计学意义(P>0.05);12周后B组小鼠血清TC、LDL-C水平显著高于A组(P<0.05);C、D组小鼠的血清TC、LDL-C水平均低于A组(P<0.05),而B组的TG、HDL-C水平均低于其余3组。B组主动脉粥样斑块面积明显大于A、C及D组(P<0.05),C、D两组的斑块面积小于A组(P<0.05);B组血清SOD活力明显下降。结论:早期ERT可改善血脂代谢,抑制血清SOD活性的下降,从而抑制大鼠动脉粥样硬化形成。

Objective： To understand the effect of estrogen replacement therapy （ERT） in the early phase on atherosclerosis in rats fed by high fat diet. Methods： 28 rats were divided into 4 groups： group A （sham operation）, group B （ovariectomized without estradiol）, group C （ovariectomized with low- dose estradiol） and group D （ovariectomized with high -dose estradiol） . All the rat in 4 groups were given 1% cholesterol diet for 12 weeks, the levels of blood lipids, estradiol and serum superoxide dismutase （SOD） activity were detected before the operation and on the fourth and twelfth weeks. Results： After 12 weeks, the level of estradiol in group B was significandy lower than that in group A （ P 〈 0.05 ）, the level of estradiol in group D was significantly higher than that in group A （ P 〈 0. 05 ）, there was no difference in the level of estradiol between group C and group A （ P 〉 0. 05 ） ; the levels of TC and LDL - C in group B were significantly higher than those in group A （ P 〈 0. 05 ） ; the levels of TC and LDL - C in group C and group D were significandy lower than those in group A （ P 〈 0.05 ） , and levels of TC and LDL - C in group B were the lowest among four groups. The aortic plaque area in group B was the largest among four groups （ P 〈 0. 05 ）, the aortic plaque areas in group C and group D were smaller than that in group A （ P 〈 0. 05 ） . The serum SOD activity of group B decreased significantly. Conclusion： Estrogen replacement therapy in the early phase can improve the metabolism of the serum hpids, increase the SOD activity and inhibit the formation of atherosclerosis.