Central alpha-MSH, energy balance, thermal balance, and antipyresis

Intracerebroventricular administration of alpha-MSH in young adult rats enhanced metabolic rate and caused a dose-dependent suppression of food intake, exhibiting a coordinated catabolic pattern. However, the thermoregulatory effects did not seem to be coordinated: the rising heat production was accompanied by a practically simultaneous tendency for rise in heat loss (skin vasodilatation), and the final core temperature either increased or decreased depending on which rise prevailed. The effect on heat loss possibly explains the antipyretic properties of the peptide.