Jaskiw G E, Karoum F K, Weinberger D R
Clinical Brain Disorders Branch, National Institute of Mental Health, NIMH Neuroscience Center at St. Elizabeths, Washington, DC 20032.
Brain Res. 1990 Nov 26;534(1-2):321-3. doi: 10.1016/0006-8993(90)90149-6.
This study assessed the possible influence of the medial prefrontal cortex (MPFC) on the response of subcortical dopamine (DA) systems to subchronic, mild stress. DA and its metabolites as well as noradrenaline were assayed in the nucleus accumbens and corpus striatum, 1 and 7 days after one week of daily intraperitoneal saline injections (Stress) or no handling (No stress), in rats with sham (Sham) or ibotenic acid (IA) lesions of the MPFC. One day after the last saline injection the level of dihydroxyphenylacetic acid (DOPAC) was elevated in the nucleus accumbens of IA/Stress rats in comparison to the Sham/No stress, Sham/Stress, and IA/No Stress groups. Levels of mesolimbic DA, DOPAC and homovanillic acid were still elevated 7 days after the last injection in IA/Stress animals in comparison to all other groups. There were no other significant differences between the groups. The data suggest that in rats with MPFC impairment, mild subchronic stress can induce alterations in mesolimbic DA activity that persist beyond the duration of the stress.
本研究评估了内侧前额叶皮质（MPFC）对皮质下多巴胺（DA）系统对亚慢性轻度应激反应的可能影响。在对MPFC进行假手术（Sham）或注射鹅膏蕈氨酸（IA）损伤的大鼠中，于每日腹腔注射生理盐水一周（应激组）或不进行任何处理（非应激组）后的第1天和第7天，测定伏隔核和纹状体内的DA及其代谢产物以及去甲肾上腺素。与假手术/非应激组、假手术/应激组和IA/非应激组相比，在最后一次注射生理盐水后的第1天，IA/应激组大鼠伏隔核中的二羟基苯乙酸（DOPAC）水平升高。与所有其他组相比，在最后一次注射后的第7天，IA/应激组动物中脑边缘系统的DA、DOPAC和高香草酸水平仍升高。各组之间无其他显著差异。数据表明，在MPFC受损的大鼠中，轻度亚慢性应激可诱导中脑边缘系统DA活性发生改变，且这种改变在应激结束后仍持续存在。
