The Secondary Conditioned Response of Rats and the Effects of Some Psychopharmacological Agents
Journal of Pharmacy and Pharmacology – September 01, 1959
Source: OpenAlex
Summary
Chlorpromazine, promazine, reserpine, and morphine effectively block both primary and secondary avoidance responses in rats without impairing motor function. In contrast, meprobamate and hydroxyzine suppress the secondary response but not the primary one. Mescaline and iproniazid specifically depress conditioned behavior. Notably, certain drugs like barbitone sodium only inhibit responses at neurotoxic doses. This study proposes a new classification of tranquilizing agents and suggests that examining secondary conditioned avoidance responses could enhance understanding of drug effects on behavior.
Abstract
Abstract The secondary conditioned response has been studied in rats in an experimental avoidance situation. The activity of seventeen drugs has been tested upon the secondary conditioned response developed on a stable basis after an appropriate period of training. Chlorpromazine, promazine, reserpine and morphine block the secondary avoidance conditioned response as well as the usual avoidance conditioned response, in doses not affecting the motor function. Meprobamate, hydroxyzine, azacyclonol, phenaglycodol and phenobarbitone sodium have no specific inhibitory action on the avoidance conditioned response, but suppress the secondary conditioned response. A specific depression of conditioned behaviour is also produced by mescaline and iproniazid. Barbitone sodium, glutethimide, L1458 and mephenesin inhibit the conditioned responses only at neurotoxic doses. On the basis of these findings a new classification of “tranquillising agents” is proposed. It is also suggested that the systematic study of the secondary conditioned avoidance response of rats, may provide a useful experimental approach for studying the specific behavioural action of drugs.