Effects of reserpine stress-induced various responses in rats

The effects of reserpine, an amine depletor, on the thermoregulation, gastric ulceration and emotional responses were compared with those of N^6-cyclohexyl adenosine (CHA), an aadenosine A-1 receptor agonist in stressed and non stressed rats. Subcutaneous injection of reserpine produced hypothermia and gastric lesions even in non-stressed rats, and potentiated the hypothermia but did not produce gastric lesions in stressed rats. To the contrary, intracerebral injection of reserpine produced hyperthrmis snd did not produce gastric lesions in stressed or non-stressed rats. Both intracerbral and subcutaneous injection os CHA produced hypothermia and gastric lesions, which were potentiated in stressed rats. Reserpine (s. c.)-induced gastric lesiona in stressed rats were not inhibited by caffeine, an adenosine receptor antagonist, suggesting that the lesion formation by reserpine may not be due to the activation of central adenosine A-1 receptor. Stress-induced hyperemotional behaviors such as struggling and defecation were inhabited by either subcutaneous or intraventricular injection of reserpine and CHA. These results suggest that reserpine-induced hypothermia and gastric ulceration is peripheral action, and the inhibitory effects of reserpine and CHA on stress-induced hyperemotinal responses may be due to the central actions.