Tsuda A, Tanaka M, Ida Y, Tsujimaru S, Ushijima I, Nagasaki N
Pharmacol Biochem Behav. 1986 Jan;24(1):115-9. doi: 10.1016/0091-3057(86)90053-5.
The present study examined alterations of brain noradrenaline (NA) turnover as a function of preshock and psychological stress treatments, by measuring contents of NA metabolite, 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4), in discrete brain regions of male Wistar rats. Psychological stress induced by exposing to the sight, sound and odor of other rats being shocked produced higher levels of MHPG-SO4 in the hypothalamus, amygdala and locus coeruleus (LC) region, as well as higher levels of plasma corticosterone. Preshock experienced rats also showed marked increases of MHPG-SO4 levels in the same regions described above and elevated plasma corticosterone levels when placed but not shocked in the same environment in which the rats had previously received shocks. The effects of psychological stress on brain NA turnover were affected by the animal's shock history preferentially in the hypothalamus and amygdala. These results suggest that: a purely psychological stressor caused acutely enhanced NA turnover in specific brain regions; regional NA activity appeared to be reinstated simply by reexposure to the environment previously associated with shock; preshock experience further intensified the enhancement of amygdaloid NA turnover evoked by psychological stress. An additional experiment, studying the aftereffects of preshock experience, clearly showed that these findings result from sensitization or conditioning to the environment previously paired with shock, and not merely from the aftereffects of the shock per se.
本研究通过测量雄性Wistar大鼠离散脑区中去甲肾上腺素（NA）代谢产物3-甲氧基-4-羟基苯乙二醇硫酸盐（MHPG-SO4）的含量，研究了脑内NA周转率随休克前和心理应激处理的变化。暴露于其他大鼠遭受电击时的视觉、声音和气味所诱发的心理应激，在下丘脑、杏仁核和蓝斑（LC）区域产生了更高水平的MHPG-SO4，以及更高水平的血浆皮质酮。经历过休克前处理的大鼠，当被放置在它们先前接受电击的相同环境中但不进行电击时，上述相同区域的MHPG-SO4水平也显著升高，血浆皮质酮水平也升高。心理应激对脑内NA周转率的影响，在下丘脑和杏仁核中优先受到动物休克史的影响。这些结果表明：纯粹的心理应激源会导致特定脑区的NA周转率急性增强；仅仅通过再次暴露于先前与休克相关的环境，区域NA活性似乎就会恢复；休克前经历进一步加剧了心理应激诱发的杏仁核NA周转率的增强。另一项研究休克前经历后遗症的实验清楚地表明，这些发现是由于对先前与休克配对的环境产生了敏感化或条件作用，而不仅仅是休克本身的后遗症。
