ACUTE AND REPEATED ECS TREATMENT INCREASES CRF, POMC AND PENK GENE-EXPRESSION IN SELECTED REGIONS OF THE RAT HYPOTHALAMUS

THE purpose of this study was to investigate the effects of acute and repeated electroconvulsive shock (ECS) on corticotropin releasing fact or (CRF), proopiomelanocortin (POMC) and proenkephalin (PENK) gene exp ression in selected regions of the brain and pituitary of the rat. Acu te ECS increased CRF gene expression in the paraventricular nucleus (P VN) by 20%, an effect that was further enhanced to 38% when rats recei ved repeated ECS treatment. Acute and repeated ECS increased POMC gene expression in the arcuate nucleus (ARC) by 49-59% but failed to alter these mRNA levels in the anterior lobe (AL) of the pituitary gland. P ENK gene expression was increased by 35% in the nucleus accumbens (NA) and by 180% the ventromedial nucleus (VMN) after acute or repeated EC S treatment but no significant changes were found in the PVN or striat um (ST). Taken together, these results indicate a differential CRF and opioid gene expression regulation after acute or repeated ECS treatme nt that may be relevant to their therapeutic or side effects in depres sion.