足部电击应激对先前反复暴露于甲基苯丙胺的大鼠脑区单胺代谢及条件性僵立习得的影响。

Effects of footshock stress on regional brain monoamine metabolism and the acquisition of conditioned freezing in rats previously exposed to repeated methamphetamine.

Tsuchiya K, Inoue T, Izumi T, Hashimoto S, Koyama T

Department of Psychiatry, Hokkaido University School of Medicine, Sapporo, Japan.

Prog Neuropsychopharmacol Biol Psychiatry. 1996 Oct;20(7):1239-50. doi: 10.1016/s0278-5846(96)00109-1.

Abstract

Effects of footshock stress on regional brain DA and 5-HT metabolism and the acquisition of conditioned fear in male Wistar-King rats previously exposed to repeated MA were examined. 2. MA-pretreated rats exhibited more freezing than control rats in the conditioned fear test. 3. The HVA levels in the striatum was elevated by footshock only in MA-treated rats but not saline-treated rats. Furthermore, MA-treated rats showed increased metabolism of DA in the mPFC, even when placed in the shock chamber without shocks. 4. The brain serotonergic responsiveness to fear conditioning was also attenuated by repeated administration of MA. 5. These results suggest that not only the brain DA systems but also the brain 5-HT systems play an important role for the development of MA-induced emotional hypersensitivity to stress.

摘要

研究了足部电击应激对先前反复给予甲基苯丙胺（MA）的雄性Wistar-King大鼠脑区多巴胺（DA）和5-羟色胺（5-HT）代谢以及条件性恐惧习得的影响。2. 在条件性恐惧测试中，MA预处理的大鼠比对照大鼠表现出更多的僵住行为。3. 仅在MA处理的大鼠中，足部电击使纹状体中高香草酸（HVA）水平升高，而生理盐水处理的大鼠则未出现此现象。此外，即使将MA处理的大鼠置于无电击的电击箱中，其内侧前额叶皮质（mPFC）中的DA代谢也会增加。4. 反复给予MA也会减弱大脑对恐惧条件作用的5-羟色胺能反应性。5. 这些结果表明，不仅脑DA系统，而且脑5-HT系统在MA诱导的对应激的情绪超敏反应的发展中都起重要作用。