P物质对大鼠离体腺垂体黄体生成素和卵巢孕酮分泌的影响

EFFECTS OF SUBSTANCE P ON THE INTERNAI SECRETION OF HYPOTHALAMUS,ANTERIOR PITUITARY AND OVERYIN RATS IN VITRO

本实验采用大鼠间情期和情期离体下丘脑、腺垂体和卵巢组织培养顺序灌流技术，放射免疫测定法及液体闪烁测量技术，观察了Ｐ物质（ＳＰ）对腺垂体黄体生成素（ＬＨ）和卵巢孕酮分泌的影响。结果表明：（１）在间情期，ＳＰ可作用于下丘脑水平，从而抑制腺垂体ＬＨ的分泌，而对垂体本身则无直接作用。（２）在情期，ＳＰ可直接作用于垂体水平，抑制腺体ＬＨ分泌，而使卵巢孕酮的分泌减少。（３）ＳＰ对间情期和情期离体卵巢组织孕酮的分泌均无直接影响。结果提示：ＳＰ很可能作为一种抑制性调节肽在大鼠性周期的不同时期中，调节下丘脑中ＧｎＲＨ或腺垂体中ＬＨ的分泌，从而调节大鼠正常性周期中性激素的水平和生殖功能。

In order to investigate effects of substance P on secretion of GnRH, LH and progesterone in rats in vitro,tissue cultruer and sequence perfusion in hypothalamus,anterior pituitary gland and ovary technique was used.LH·in the anterior pituitary culture fluid was detected by RIA and progesterone in ovary culture solution was measured by liquid soinfillation counting method. The results showed that SP played a central inhibitory role in controlling internal secretion of the reproduction axis and its target was varied with different periods of sexual cycle.During diestrus,SP inhibited GnRH releasing in hypothalamus,so that result in a declined LH releasing in anterior pituitary.But during oestrus,SP inhibited the stimulatory effect of GnRH on the releasing of LH in pituitary,so that bring about a declined progesterone releas in ovary.The results also showed that SP had no direct effect on progesterone releasing in culture ovary.The results indicated that SP maybe works as an inhibitary regulatory peptide in controlling GnRH or LH in different periods of sexual cycle.