REPEATED SWIM STRESS AND PERIPHERAL-TYPE BENZODIAZEPINE RECEPTORS

The effect of daily forced swimming (15 min) of rats for 21 consecutiv e days on peripheral-type bentodiazepine receptors (PER) was investiga ted. A significant reduction (-17%; p < 0.05) was observed in renal PE R in the stressed animals. A nonsignificant reduction of -18% was dete cted in adrenal PER. The maximal binding capacity of [H-3]PK 11195 was unaltered in the liver, heart, testis and thymus. It seems that the k idney is especially sensitive to repeated stress. The renal PER reduct ion may be related to habituation to stress, and may reflect an adapta tory mechanism aimed at preventing longterm stress-induced overactivit y of the renin-angiotensin system.