Alpha-melanocyte stimulating hormone (MSH) antagonizes the anorexia by corticotropin releasing factor (CRF)

We examined a hypothesis that alpha-Melanocyte Stimulating Hormone (MSH) can antagonizes the anorexia induced by intracerebroventricular injection of corticotropin releasing factor (CRF). Food intake of the rats deprived of food for 18 h was significantly inhibited by 4 h after intracerebroventricular injection of CRF. alpha-MSH also suppressed food consumption by 4 h after the treatment. However, simultaneous administration of alpha-MSH attenuated the anorexic effect of CRF at 0-2 h period and food consumption for 4 h was equal to controls. In addition, simultaneous administration of alpha-MSH deleted the stimulatory effects of CRF on serum corticosterone levels. The present experiment demonstrated that alpha-MSH can antagonizes the anorexia and activation of hypothalamo-pituitary-adrenal axis by CRF, suggesting that the processing step of proopiomelanocortin may be important for the induction of anorexia elicited by CRF.