SIMILAR EFFECTS OF TREATMENT WITH DESIPRAMINE AND ELECTROCONVULSIVE SHOCK ON 5-HYDROXYTRYPTAMINE-1A RECEPTORS IN RAT-BRAIN

The effect of chronic and acute treatment with desipramine (DMI) and electroconvulsive shock (ECS) on 5-hydroxytryptamine1A (5-HT1A) receptors was determined in the cortex and the hippocampus brain regions of rats. We observed that chronic treatment with both DMI and ECS significantly decreased 5-HT1A receptors, as determined by [H-3]8-hydroxy-2-(di-n-propylamino) tetralin ([H-3]8-OH-DPAT) binding, in the cortex but not in the hippocampus. Acute treatment with DMI or ECS did not significantly alter the 5-HT1A receptors in the cortex. Neither chronic nor acute treatment influenced K(D) of [H-3]8-OH-DPAT binding in the cortex or hippocampus. These results thus suggest that in contrast to the effects on 5-HT, receptors, tricyclics as well as ECS produce similar effects on 5-HT1A receptors, suggesting that this site may represent a common site of action for antidepressant treatment.