beta-Endorphin and beta-MSH in human plasma.

The aim of this study was to establish whether or not a peptide with chromatographic and immunological properties of beta-endorphin exists in human plasma. Using direct chromatography under conditions designed to minimize generation of beta-endorphin and beta-MSH from beta-LPH, we invariably found a peptide with beta-endorphin immunoreactivity eluting in the position of beta h-endorphin on gel chromatography in samples of plasma from patients with elevated ACTH and LPH levels. beta-MSH was only found in the plasma of one patient with the ectopic ACTH syndrome.