Corticosterone facilitates retention of contextually conditioned fear and increases CRH mRNA expression in the amygdala.
Corticosterone facilitates retention of contextually conditioned fear and increases CRH mRNA expression in the amygdala.
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皮质酮有助于保留情境条件恐惧并增加杏仁核中 CRH mRNA 的表达。
DOI：
10.1016/s0166-4328(03)00216-x
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发表时间：
2004
影响因子：
2.7
通讯作者：
Rosen,JeffreyB
中科院分区：
文献类型：
--
作者：
Thompson,BarbaraL;Erickson,Kristine;Schulkin,Jay;Rosen,JeffreyB
本研究探讨了糖皮质激素管理的情绪记忆和促肾上腺皮质激素释放激素（CRH）的mRNA表达的杏仁中央核（CeA）和下丘脑室旁核（PVN）的影响。这是测试通过管理重复皮质酮（CORT）的上下文恐惧条件反射的范例。大鼠接受2.5mg/kg（s.c.）CORT或安慰剂每天两次，持续5天半，最后一次注射后2小时，大鼠进行一次试验情境恐惧条件反射。当测试保留条件性恐惧6天后，皮质醇治疗的大鼠表现出更多的恐惧条件冻结在保留测试中比车辆治疗的大鼠，这是不占的脚电击反应性增加，也没有升高血浆皮质醇。另一组大鼠在CORT给药前进行条件性恐惧，24小时后进行5天半的CORT给药，6天后进行测试;这些大鼠的条件性恐惧没有增强。最后，CORT给药导致CeA中CRH mRNA的增加和PVN的减少。这些数据表明，在恐惧条件反射之前重复给予CORT有助于获得情绪记忆，而在巩固后给予CORT不会增加情绪记忆。
The present study examined the effects of glucocorticoid administration on emotional memory and on corticotropin-releasing hormone (CRH) mRNA expression in the central nucleus of the amygdala (CeA) and the paraventricular nucleus of the hypothalamus (PVN). This was tested by administering repeated corticosterone (CORT) within a contextual fear conditioning paradigm. Rats received 2.5mg/kg (s.c.) CORT or placebo twice a day for five and a half days and, 2h after the last injection, rats were given one-trial contextual fear conditioning. When tested for retention of conditioned fear 6 days later, the CORT-treated rats displayed more fear-conditioned freezing in the retention test than vehicle-treated rats, which was not accounted for by an increase in footshock responsivity nor elevated plasma CORT. Another group of rats was fear conditioned prior to CORT administration, followed 24h later by the five and a half days of CORT, and tested 6 days later; conditioned fear was not enhanced in these rats. Finally, CORT administration produced an increase of CRH mRNA in the CeA and a decrease in the PVN. The data suggest that repeated administration of CORT given before fear conditioning facilitates the acquisition of emotional memory, whereas CORT given after consolidation does not increase emotional memory.