Leadem C A, Kalra S P
Endocrinology. 1984 Jan;114(1):51-6. doi: 10.1210/endo-114-1-51.
The effects of estradiol benzoate (EB) and progesterone (P) in vivo and P in vitro on LHRH release from perifused preoptic area-medial basal hypothalamus (POA-MBH) tissue fragments were assessed. In the first series of experiments, ovariectomized female rats were given either 10 or 30 micrograms EB on day 0, followed by either oil or 5 mg P at 1000 h on day 2. Rats were killed at 2-h intervals after P or oil injection, and the POA-MBH from these rats were incubated in a perifusion system. LHRH release from the POA-MBH of rats primed with either 10 or 30 micrograms EB displayed similar patterns; from a basal rate at 1200 and 1400 h, LHRH secretion rose to significantly higher levels at 1600 and 1800 h. This increase in LHRH release in vitro was evident from the POA-MBH obtained just before and during the afternoon LH rise in vivo. On the other hand, the LHRH secretion pattern in vitro was different in two ways when rats were treated additionally with P. First, LHRH output was significantly higher at 1200 and 1400 h than that in rats treated with 10 or 30 micrograms EB only; this pattern was maintained later at 1600 and 1800 h from the POA-MBH of rats primed with 30 micrograms EB. Second, within the EB/P-treated (EBP) group, significant elevations in the LHRH output occurred from the POA-MBH obtained at 1800 h when rats were in the midst of the LH surge. In the other series of experiments, the POA-MBH of the EB-primed rats (30 micrograms/rat) were perifused with P (10 ng/ml) or vehicle for 6 h. The mean LHRH release during the 6-h interval was significantly higher after P perifusion; the bulk of this rise was evident at 4 h. These studies show that in vitro, the LHRH output of the POA-MBH from the EB- or EBP-treated rats varies significantly during the day and that the POA-MBH of EB-treated rats secretes large amounts of LHRH in vitro, which correlate well with the afternoon LH rise. In addition, treatment with P in vivo changes the in vitro pattern of LHRH output from the POA-MBH of these EB-primed rats, whereas superfusion of P in vitro induces only a marginal stimulation of LHRH release.
评估了苯甲酸雌二醇（EB）和孕酮（P）在体内以及P在体外对经灌流的视前区-内侧基底下丘脑（POA-MBH）组织碎片释放促性腺激素释放激素（LHRH）的影响。在第一系列实验中，于第0天给去卵巢的雌性大鼠注射10或30微克EB，然后在第2天1000 h给其注射油剂或5毫克P。在注射P或油剂后每隔2小时处死大鼠，并将这些大鼠的POA-MBH在灌流系统中孵育。用10或30微克EB预处理的大鼠，其POA-MBH释放LHRH的模式相似；LHRH分泌从1200和1400 h的基础水平，在1600和1800 h升至显著更高水平。体外LHRH释放的这种增加，在体内下午促黄体生成素（LH）升高之前及期间获取的POA-MBH中很明显。另一方面，当大鼠额外接受P处理时，体外LHRH分泌模式在两方面有所不同。首先，在1200和1400 h时，LHRH输出量显著高于仅用10或30微克EB处理的大鼠；在用30微克EB预处理的大鼠的POA-MBH中，这种模式在随后的1600和1800 h得以维持。其次，在EB/P处理组（EBP组）内，当大鼠处于LH峰时，在1800 h获取的POA-MBH中LHRH输出量显著升高。在另一系列实验中，用P（10纳克/毫升）或溶媒对用EB预处理的大鼠（30微克/只）的POA-MBH进行6小时的灌流。P灌流后6小时间隔内LHRH的平均释放量显著更高；这种升高在4小时时最为明显。这些研究表明，在体外，经EB或EBP处理的大鼠的POA-MBH的LHRH输出量在一天中变化显著，且经EB处理的大鼠的POA-MBH在体外分泌大量LHRH，这与下午LH升高密切相关。此外，体内用P处理会改变这些经EB预处理的大鼠的POA-MBH的体外LHRH输出模式，而体外灌流P仅诱导LHRH释放产生轻微刺激。
