Edwards E, Harkins K, Wright G, Henn F A
Department of Psychiatry and Behavioral Science, State University of New York at Stony Brook 11794-8101.
Neuropharmacology. 1991 Jan;30(1):101-5. doi: 10.1016/0028-3908(91)90050-l.
After exposure to a 0.8 mA course of uncontrollable shocks, Sprague-Dawley rats can be differentiated into two distinct groups defined in term of their performance in a shock escape paradigm. Learned helpless (LH) rats do not learn to escape a controllable shock while non-helpless (NLH) rats learn this response as quickly as naive controls (NC) rats do. The current experiments were designed to extend our studies of 5-HT receptors in these three groups of rats. The major finding in the present study concerned post-synaptic 5-HT receptor effects in the cortex, hippocampus, septum and hypothalamus of LH rats. These included an up regulation of 5-HT1b receptors in the cortex, hippocampus and septum in LH rats. In contrast, 5-HT1b receptors in the hypothalamus of LH rats were down-regulated. These results implicate serotonergic mechanisms in the behavioral deficit caused by uncontrollable shock with a limbic-hypothalamic circuit serving as a center for adaptation to stress.
在遭受0.8毫安强度的不可控电击后,斯普拉格-道利大鼠可根据其在电击逃避范式中的表现分为两个不同的组。习得性无助(LH)大鼠不会学会逃避可控电击,而非无助(NLH)大鼠学习这种反应的速度与未受处理的对照(NC)大鼠一样快。当前的实验旨在扩展我们对这三组大鼠中5-羟色胺受体的研究。本研究的主要发现涉及LH大鼠大脑皮层、海马体、隔区和下丘脑的突触后5-羟色胺受体效应。这些效应包括LH大鼠大脑皮层、海马体和隔区中5-HT1b受体的上调。相比之下,LH大鼠下丘脑中的5-HT1b受体下调。这些结果表明,不可控电击引起的行为缺陷涉及血清素能机制,边缘-下丘脑回路是适应应激的中心。