PROLACTIN RESPONSE TO ELECTROCONVULSIVE SHOCK IN ANESTHETIZED RATS

Serum prolactin level (SPL) of anesthetized rats was measured in respo nse to electroconvulsive shock (ECS). This measurement served as an in dicator of dopaminergic and serotonergic activity. Such neurotransmitt er activity was modulated by pretreatment with cyproheptadine, parachl orophenylalanine (PCPA), pimozide, bromocriptine or L-dopa. A statisti cally significant lowered SPL was found in rats given ECS plus antiser otonergic agents, in comparison with animals receiving antiserotonergi c agent or ECS alone. When ECS was administered to rats pretreated wit h the dopaminergic blocker, pimozide, there was a significant decrease in SPL, compared with animals receiving pimozide alone. When the dopa minergic system was stimulated by dopamine agonists, there was no elev ation of SPL in response to ECS. Thus, there may be a balance between serotonergic and dopaminergic systems. The agents used in the experime nt may upset this balance and produce a change in prolactin response t o a given ECT stimulus.