Decreased sensitivity to glucocorticoid fast feedback in chronically stressed rats.
Decreased sensitivity to glucocorticoid fast feedback in chronically stressed rats.
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慢性应激大鼠对糖皮质激素快速反馈的敏感性降低。
DOI：
10.1159/000125388
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发表时间：
1990
影响因子：
4.1
通讯作者：
Dallman,MF
中科院分区：
文献类型：
--
作者：
Young,EA;Akana,S;Dallman,MF
慢性足休克后垂体前叶促肾上腺皮质激素细胞发生了许多变化。这些包括ACTH和β-内啡肽含量增加，以及对促肾上腺皮质激素释放激素（CRH）刺激的ACTH和β-内啡肽分泌的糖皮质激素负反馈丧失，而对体外检查的绵羊CRH的敏感性没有变化[9]。本研究旨在确定体外变化是否反映为体内类似变化。我们开发了一个快速反馈模式，使用5分钟的游泳应激作为挑战，注射生理盐水或皮质酮游泳前立即。皮质酮可靠地降低ACTH和β-内啡肽的反应，游泳超过30分钟的时间内研究。这种反馈抑制并没有发生在大鼠，无论是暴露于30分钟的慢性足电击7或14天，或在大鼠中，已被报道，以减少海马糖皮质激素受体的方案，每天用皮质酮治疗14天。相反，在大鼠暴露于30分钟的游泳14天的强度较小的刺激，皮质酮的快速反馈作用是完整的。这些结果表明，快速和延迟反馈皮质酮抑制机制可能会被相对较高水平的慢性应激或慢性治疗皮质酮，可能是由于海马糖皮质激素受体数量减少。
A number of changes in anterior pituitary corticotrophs occur after chronic footshock. These include increased ACTH and β-endorphin content and a loss of glucocorticoid negative feedback on corticotropin-releasing hormone (CRH)-stimulated ACTH and β-endorphin secretion, without changes in sensitivity to ovine CRH examined in vitro [9]. The present studies were undertaken to determine whether the in vitro changes were reflected by similar changes in vivo. We developed a fast feedback paradigm using a 5-min swim stress as challenge, with injection of saline or corticosterone immediately prior to swim. Corticosterone reliably decreased ACTH and β-endorphin responses to swim over the 30-min period studied. This feedback inhibition did not occur in rats that were either exposed to 30 min of chronic footshock for 7 or 14 days or in rats that were treated with corticosterone daily for 14 days in a regimen that has been reported to decrease hippocampal glucocorticoid receptors. By contrast, in rats exposed to the less intense stimulus of 30 min swim for 14 days, the fast feedback action of corticosterone was intact. These results suggest that both fast and delayed feedback corticosterone-inhibitory mechanisms may be blocked by relatively high levels of chronic stress or by chronic treatment with corticosterone, possibly as a consequence of decreased hippocampal glucocorticoid receptor number.
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影响因子：
15.9
作者：
MAK, IT;WEGLICKI, WB
通讯作者：
WEGLICKI, WB
α-生育酚-牛血清白蛋白复合物在胶束和脂质体自氧化中的抗氧化活性。
影响因子：
4.8
作者：
L. Barclay;A. M. Bailey;D. Kong
通讯作者：
D. Kong
铁超载患者肝活检中的酸性水解酶活性和溶酶体完整性。
DOI：
--
发表时间：
1976
期刊：
Clinical science and molecular medicine
影响因子：
--
作者：
T. Peters;C. Seymour
通讯作者：
C. Seymour
血色素沉着症：1980 年更新。
影响因子：
29.4
作者：
L. Powell;M. Bassett;J. Halliday
通讯作者：
J. Halliday
特发性血色素沉着病的静脉切开治疗的长期结果。
DOI：
10.1093/oxfordjournals.qjmed.a067484
发表时间：
1976
期刊：
The Quarterly journal of medicine
影响因子：
--
作者：
A. Bomford;Roger Williams
通讯作者：
Roger Williams