Feedback effects of ovarian steroids on the hypothalamic-hypophyseal axis in the rabbit.
Feedback effects of ovarian steroids on the hypothalamic-hypophyseal axis in the rabbit.
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卵巢类固醇对兔子下丘脑-垂体轴的反馈作用。
DOI：
10.1095/biolreprod35.4.1009
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发表时间：
1986
影响因子：
3.6
通讯作者：
Spies,HG
中科院分区：
文献类型：
--
作者：
Pau,KY;Orstead,KM;Hess,DL;Spies,HG
本研究在正常雌兔（INT）和去卵巢雌兔（OVEX）中检测了雌二醇-17 β（E2）和20α-羟基孕甾-4-烯-3-酮（20αOH）的反馈效应。我们测量了激素诱导的内源性促性腺激素释放激素（GnRH）的变化，从连续10分钟的下丘脑灌注液样品，外周血浆促黄体激素（LH）和促卵泡激素（FSH）的同时变化，以及垂体反应性的改变，即，6个治疗组的个体剂量给予50 ng、250 ng和1 µg外源性GnRH后，血浆LH（Δ LH）和血浆FSH（Δ FSH）的增量。这些小组是：INT接受，OVEX接受，OVEX接受1个（1 E2）或2个（2 E2）E2填充的硅橡胶胶囊，OVEX接受20α OH填充的胶囊（20αOH），OVEX接受E2和20αOH两种胶囊（1 E2+ 20αOH）.卵巢切除增加了下丘脑GnRH和垂体LH和FSH的脉冲式释放，并增加对外源性GnRH的LH反应（Δ LH）（OVEX vs. INT，p<0.05）。在卵巢切除术时补充E2可防止GnRH和促性腺激素分泌增加以及在未处理的OVEX雌兔中观察到的Δ LH增加。20αOH组下丘脑GnRH释放量低于OVEX组（P<0.05），与INT组无差异。20αOH组垂体LH、FSH和Δ LH的释放与OVEX组无差异，但均高于INT组（p<0.05）。1 E2+ 20αOH组下丘脑GnRH脉冲频率较低（p<0.05），但1 E2+ 20αOH组的Δ LH与1 E2或20αOH组无差异。1个E2+ 20αOH组和1个E2组，但激素对Δ FSH的影响不明显。结果提示，在家兔体内，E2对下丘脑和垂体均有抑制作用，而20αOH则抑制下丘脑GnRH释放，促进垂体LH反应。
The feedback effects of two ovarian steroids, estradiol-17β (E2) and 20α-hydroxypregn-4-en-3-one (20αOH), were examined in both intact (INT) and ovariectomized (OVEX) does. We measured steroid-induced alterations in endogenous gonadotropin-releasing hormone (GnRH) from sequential 10-min samples of hypothalamic perfusates, simultaneous changes in peripheral plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the modification of pituitary responsiveness, i.e., increments in plasma LH (Δ LH) and plasma FSH (Δ FSH), after 50 ng, 250 ng, and 1 µg of exogenous GnRH in individual does of 6 treatment groups. The groups were: INT does, OVEX does, OVEX does receiving either one (1 E2) or two (2 E2) E2-filled Silastic capsules, OVEX does receiving a 20αOH-filled capsule (20αOH), and OVEX does receiving both capsules of E2and 20αOH (1 E2+ 20αOH).Ovariectomy enhanced the pulsatile release of hypothalamic GnRH and pituitary LH and FSH, and increased the LH response (Δ LH) to exogenous GnRH (OVEX vs. INT, p<0.05). Replacement of E2at the time of ovariectomy prevented the increased GnRH and gonadotropin secretion as well as the enhanced Δ LH that were observed in untreated OVEX does. The release of hypothalamic GnRH in the 20αOH group was lower (p<0.05) than that in the OVEX group and not different from that in the INT group. The release of pituitary LH and FSH and the Δ LH in the 20αOH group was not different from that in the OVEX group, but these parameters were greater (p<0.05) than those in the INT group. The hypothalamic GnRH pulse frequency in the 1 E2+ 20αOH group was lower (p<0.05) than that in either the 1 E2or the 20αOH group, but the Δ LH in the 1 E2+ 20αOH group was not different from that in either the 1 E2or the 20αOH group.The highest dose (1 µg) of exogenous GnRH stimulated a modest increase in FSH in the OVEX, 20αOH, 1 E2+ 20αOH, and 1 E2groups; but a steroid effect on Δ FSH among these 4 groups was not apparent. These results suggest that in the rabbit, E2exerts its inhibitory effects on both the hypothalamus and the pituitary, whereas 20αOH suppresses hypothalamic GnRH release and facilitates pituitary LH responsiveness.
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正常和卵巢切除大鼠的外周血浆和下丘脑中的黄体生成素释放激素。
影响因子：
4.1
作者：
J. E. Wheaton;S. Mccann
通讯作者：
S. Mccann
黄体生成素释放因子对雌性大鼠垂体前叶的启动作用。
DOI：
10.1677/joe.0.0620573
发表时间：
1974
期刊：
The Journal of endocrinology
影响因子：
--
作者：
M. Aiyer;S. Chiappa;G. Fink
通讯作者：
G. Fink
体外性类固醇对垂体对 LH 和 FSH 释放激素反应的影响。
影响因子：
4.8
作者：
A. Schally;T. Redding;A. Arimura
通讯作者：
A. Arimura
雌二醇在控制恒河猴促性腺激素分泌中的负反馈和正反馈作用位点。
影响因子：
4.8
作者：
Y. Nakai;T. Plant;D. Hess;E. Keogh;E. Knobil
通讯作者：
E. Knobil
影响因子：
4.8
作者：
DIERSCHK.DJ;BHATTACH.AN;KNOBIL, E
通讯作者：
KNOBIL, E