Abstract: | Fifteen-day chronic stress with randomized footshock reinforcement (group 4) causes profound steady disturbances in the animal behavior. With the use of regular aversive reinforcement in the shuttle-box the rats were divided into two groups: "escaping" (group 2) and "non-escaping" (group 3). Minor behavioral disturbances were observed in group 2, moderate in group 3 and maximum in group 4. In the latter group "down-regulation" of beta-adrenoceptors and benzodiazepine receptors was observed. The receptor changes appear to be rather the result of psychogenic factors caused by randomized reinforcement than of physical stress as such. |