Neurochemical and behavioral effects of green tea (Camellia sinensis) as observed in animals exposed to restraint stress.

Clinical studies on psychiatric patients suggest that life events stress precipitates depression. The possible involvement of 5-Hydroxy tryptamine (5-HT; Serotonin) in depression and other behavioral deficits is also suggested by clinical studies. As a natural stimulant, green tea (Camellia Sinensis) diminishes stress, worry and anxiety, allowing the brain to focus and concentrate better. Previously we have reported that beneficial effects of green tea might be associated with altered levels of 5-HT, which in turn may help in coping with stress. Present study therefore deals with monitoring the behavior and neurochemical profile of single restrained stress in animals previously administered (for 5 weeks) with green tea. Activities in light dark activity box were monitored 1hr post restraint stress. Cumulative food intake values were monitored 24hr post restraint stress. 24hr after restrained stress, rats were decapitated to collect plasma and brain samples. Brain samples were kept stored at -70οC until neurochemical analysis by HPLC-EC. Findings illustrate that although food intake was decreased in both green tea- as well as water treated rats, stress-induced anxiogenic effects were attenuated in green tea treated rats. Tone of 5-HT was also normalized in restrained animals. Results suggest beneficial effects of green tea in coping the stressful conditions/stimuli are related to altered 5-HT metabolism.