Matt D W, LaPolt P S, Judd H L, Lu J K
Neuroendocrinology. 1986;42(1):21-7. doi: 10.1159/000124243.
In female rats ovariectomy (OVX) on the morning of diestrus day 2 resulted in a prompt (within 8 h) and gradual increase in LH release, whereas a similar operation on estrus did not raise serum LH until 24 h later. In proestrous females, OVX in the morning neither prevented the anticipated LH surge on that evening, nor increased LH release on the next morning. Since circulating concentrations of estradiol (E2) are progressively increased during diestrus day 2 and proestrus, this pattern of E2 secretion may affect the acute increase in LH secretion following OVX. To test such a hypothesis, we examined the effects of large, sustained or large, transient increases in circulating estrogen on the subsequent increase in gonadotropin secretion after OVX. On the morning of diestrus day 1 a subcutaneous injection of 20 micrograms estradiol benzoate (EB) produced prompt and large increases in both serum E2 and estrone (E1) for about 2 days, despite OVX of females at 24 h after the EB injection. An injection of 20 micrograms 17 beta-estradiol (E2) also promptly increased both serum E2 and E1. micrograms E2 injection were twice that observed after 20 micrograms EB, and both E2 and E1 returned to low baseline values within 24 h after the E2 injection. In contrast, administration of 1 microgram EB only produced small and transient rises in serum E2 and E1.(ABSTRACT TRUNCATED AT 250 WORDS)
在动情周期第2天的间情期上午对雌性大鼠进行卵巢切除术（OVX），会导致促黄体生成素（LH）释放迅速（8小时内）且逐渐增加，而在发情期进行类似手术则直到24小时后血清LH才升高。在动情前期的雌性大鼠中，上午进行OVX既不能阻止当晚预期的LH高峰，也不会增加次日上午的LH释放。由于在间情期第2天和动情前期雌二醇（E2）的循环浓度逐渐升高，这种E2分泌模式可能会影响OVX后LH分泌的急性增加。为了验证这一假设，我们研究了循环雌激素的大幅持续增加或大幅短暂增加对OVX后促性腺激素分泌后续增加的影响。在动情周期第1天上午皮下注射20微克苯甲酸雌二醇（EB），尽管在注射EB后24小时对雌性大鼠进行了OVX，但血清E2和雌酮（E1）在约2天内迅速大幅升高。注射20微克17β - 雌二醇（E2）也能迅速增加血清E2和E1。20微克E2注射后的升高幅度是20微克EB注射后观察到的两倍，且E2和E1在E2注射后24小时内均恢复到低基线值。相比之下，注射1微克EB仅使血清E2和E1产生小幅短暂升高。（摘要截取自250字）
