Effects of chronic ethanol treatment on α-MSH concentrations in rat brain and pituitary

Male Sprague-Dawley rats were chronically treated with a liquid diet containing 6.5% ( v v ) ethanol or equicaloric sucrose. Rats were killed after 21 days of treatment. α-MSH-like immunoreactivity was measured in the intermediate lobe of the pituitary gland and in several brain regions. Chronic ethanol treatment significantly reduced α-MSH-like immunoreactivity in the pituitary gland; in the arcuate nucleus of the hypothalamus and in the substantia nigra. The results of this study confirm the earlier findings that chronic ethanol treatment reduces POMC biosynthesis in the pituitary gland and in the central nervous system.