甾体避孕药对动情前期大鼠垂体贮存与释放LH的影响

THE EFFECT OF STEROIDAL CONTRACEPTIVES ON THE PITUITARY LH STORAGE AND RELEASE IN PROESTROUS RAT

本实验利用动情前期大鼠垂体对GnRH的激发效应作为模型,观察不同类型甾体避孕药(抗孕-53,18-甲基炔诺酮)处理前后垂体贮存和释放LH的关系,抗孕-53处理组剂量为3mg、0.75mg;18-甲基炔诺酮为4mg、1mg各溶于茶油0.5ml,对照组为茶油0.5ml。大鼠经两次静脉注射GnRH,其间隔为60min。血浆LH浓度达到高峰时(150min)取出垂体,用干冰速冻,称重,匀浆。放射免疫测定血浆和垂体组织内LH含量。结果表明:LH的贮存和释放有一定关系,抗孕-53处理组血浆LH浓度升高,垂体LH含量变化不明显,18-甲基炔诺酮处理组血浆LH浓度降低,垂体LH含量升高。这现象表明不同甾体避孕药对垂体释放与贮存LH有不同的影响。

The pituitary responsc to GnRH in proestrous rate treated with steroidal contraceptives (Anordrin or Levonorgestrel) was studied. The dose of Anordrin for treated group was 3 mg or 0.75 mg/0.5 ml tea oil, for Levonorgestrel treated group 4 mg or 1 mg/0.5 ml tea oil and for control group was 0.5 ml tea oil. The rats were administrated with two injections of GnRH through external jugular vein, the interval was 60 minutes. LH contents of the plasma and pituitary homogenates at 150 minutes were measured by radioimmunoassay.The results indicated that LH contents in the plasma increased remarkably while that in the pituitaries showed Slight decrease, but with no statistical significance in Anordrin treated groups.On the contrary, in Levonorgestrel treated groups, the plasma LH concentration decreased while pituitary LH content increased significantly. The results indicated that different type of steroidal contraceptives might influence the anterior pituitary LH release and storage.