Molecular forms of alpha-melanocyte-stimulating hormone in pheochromocytoma tissue

The molecular forms of alpha-melanocyte-stimulating hormone (MSH) in pheoch romocytoma tissues have been characterized using reversed-phase HPLC and ra dioimmunoassay. Six alpha-MSH-related peptides were detected. Three of the six peaks had elution times identical to those of synthetic desacetyl-alpha -MSH, alpha-MSH and diacetyl-alpha-MSH. The remaining three forms of the al pha-MSH-like immunoreactivity suggest a different processing of proopiomela nocortin in this tissue than in the intermediate lobe of the pituitary glan d. Current results confirm that alpha-MSH are present in human pheochromocy toma and suggest that alpha-MSH has role in the pathophysiology of this tis sue.