薬理と治療

Abstract

Background Rosmarinic acid is one type of plant－derived natural polyphenol that is abundantly present in perilla, rosemary, lemon balm, etc., and that has an antioxidant effect, an anti－inflammatory effect, an antibacterial effect, an anti－allergic effect, and an antidepressant effect. In this research, using a rat social isolation stress model, the anti－stress effect of rosmarinic acid was verified from the perspective of the nervous system, the endocrine system and the immune system. Methods Twenty－four male Wistar rats were randomly divided into a non－stress group （Control）, a non－stress, RA administration group（Control＋RA）, a stress group（Stress）, and a stress, RA administration group（Stress＋RA）. For stress loading, each rat was kept in its own cage for a week, while for the Control and Control＋RA groups, rats were kept three to a cage. Intraperitoneal administration of RA was performed daily（3.0 mg／kg）. One week later, aggression was evaluated（stick biting duration）. Blood plasma corticosterone concentration（EIA method）and spleen Natural killer（NK）cell activity（4－hour 51Cr release method）were studied. Results Compared to the Control group, the Stress group showed a significant increase in aggression, and blood plasma corticosterone concentration also increased, but in the Stress+RA group, these were significantly inhibited. In the Stress group spleen NK cell activity decreased, but in the Stress＋RA group this was significantly inhibited. Conclusions The administration of RA controlled the activations of the sympathetic nervous system and the endocrine system caused by stress. The authors concluded that RA had an anti－stress effect.