Alterations in rat hippocampal norepinephrine and serotonin levels under physical exercise and psychological stress / 中国病理生理杂志

ABSTRACT

AIM: This study is to determine changes of hippocampal norepinephrine (NE) and serotonin (5 -HT) in long term physical exercise and chronic psychological stress, and to study the roles of the two monoamine transmitters in the effect of exercise counteracting stress - induced hippocampal damages in brain. METHODS: Levels of hippocampal NE and 5 - HT in rats undergoing 4 - week voluntary wheel running exercise (exercise group) or 3 - week restraint stress (stress group) or 4 - week exercise and 3 - week stress (exercise - stress group) were detected by high - performance liquid chromatography using electrochemical detection. RESULTS: It is showed that levels of hippocampal NEand 5 - HT increased significantly (P < 0. 01) in the exercised rats, and in the stressed rats, hippocampal 5 - HT levelssignificantly decreased(P < 0. 05). Additionally, the NE levels maintained significant high (P < 0. 01) in exercise -stressed rats compared to the pure stressed ones. On the other hand, no obvious difference was observed in hippocampal5 - HT levels between stress group and exercise - stress group, which were all significant lower (P < 0. 05) than that in exercise group. CONCLUSION: It is suggested that both the NE and 5 - HT may play important roles in mediating the exercise-induced positive effects and the 5 - HT may play an important role in stress - induced negative effects on the hippocampus. Moreover, NE may take more action in the exercise attenuating stress - induced hippocampal damages. The hippocampal NE may be more susceptible to exercise, and the hippocampal 5 - HT may be more susceptible to stress.`