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

The molecular forms of alpha-melanocyte-stimulating hormone (MSH) in pheochromocytoma tissues have been characterized using reversed-phase HPLC and radioimmunoassay. 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 alpha-MSH-like immunoreactivity suggest a different processing of proopiomelanocortin in this tissue than in the intermediate lobe of the pituitary gland. Current results confirm that alpha-MSH are present in human pheochromocytoma and suggest that alpha-MSH has role in the pathophysiology of this tissue.