Chronic electroconvulsive shock but not lithium reduces density of (+)[3H]pentazocine binding sites in rat hippocampus.

The aim of the present study was to investigate the effect of chronic treatment with electroconvulsive shock (ECS) or lithium on (+)[3H]pentazocine binding to sigma-1 receptors in the rat hippocampus. Chronic ECS resulted in a reduction in the density with no change in affinity of (+)[3H]pentazocine binding to sigma-1 receptors in the rat hippocampus. Chronic lithium administration, however, failed to affect this binding. These data suggest that sigma-1 receptors may be involved in the mechanism of antidepressive but not antimanic therapy.