大豆异黄酮对去势大鼠类雌激素样作用的研究

Research on estrogen-like function of soybean isoflavones in ovariectomized rats

目的探讨植物雌激素大豆异黄酮对去卵巢大鼠生长发育、血液生化指标、骨营养状况及子宫增生的影响及作用机制。方法选择60只雌性SD大鼠进行腹腔假手术或切除双侧卵巢后,随机分为6组,每组10只,分别为假手术组、去卵巢对照组、雌激素对照组(β-雌二醇0.2 mg/kg.bw)和大豆异黄酮剂量为30、60、120 mg/kg.bw的高、中、低3个剂量组,分别用含有β-雌二醇、不同剂量大豆异黄酮的饲料和基础饲料喂养7周,实验期间记录各组大鼠的体重和摄食量,并计算食物利用率。实验结束后测定大鼠血清生化指标、股骨密度、骨钙含量,同时对子宫进行病理组织学观察。结果大豆异黄酮各剂量组大鼠的股骨中点和中、高剂量组远心点骨密度均高于去卵巢对照组(P<0.05或P<0.01);大豆异黄酮各剂量组的生长发育、血清生化指标、骨钙含量以及子宫萎缩程度与去卵巢对照组比较差异无统计学意义(P>0.05)。结论大豆异黄酮能够增加去势大鼠的骨密度,可有效防止卵巢切除大鼠的骨量丢失,具有类雌激素样作用,未见对子宫有明显的增生作用。

Objective To find impacts and mechanism of soybean isoflavones on growth and development, serum biochemical indices, bone mass and uterus hyperplasia in ovariectomized rats. Methods 60 female SD rats were sham-operated or ovariectomized by abdominal cavity operation and divided randomly into 6 groups of Sham, Ovx, estrogen group （ β-estradiol 0.2 mg/kg, bw） and high, middle, low isoflavone dosage groups（30,60,120 mg/kg, bw） which were fed for 7 weeks. Weight and food intake of each group of rats were recorded as well as the food utilization rates. Serum biochemical indices, bone mineral density（ BMD ）, calcium content and uterus hyperplasia were measured when experiment finished. Results Bone density was significantly higher in soybean isoflavane dosage groups than which in OVX group（ P 〈0.05 ,P 〈 0.01）. The growth of rats, serum biochemical indices, bone calcium and the degree of uterus atrophy in soybean isoflavone dosage groups were observed no significant difference with OVX group （ P 〉 0.05）. Conclusion Soybean isoflavones might impose estrogen-like effects on ovariectomized rats which could prevent bone mass loss induced by ovariectomy, whereas no significant impact on uterus hyperplasia.