In Vitro and in Vivo Evidence that the C-Terminus of Preproenkephalin-A Circulates as an 8500-Dalton Molecule

Abstract

Abstract

One of the major immunoreactive components of the enkephalin precurser BAM-22P in extracts of adrenal medulla is a molecule of ≈8500 Da. A similar component is detected, after gel-permeation chromatography, in extracts of bovine plasma and in culture medium harvested from acetylcholine-stimulated bovine adrenomedullary cells in culture. Simultaneous detection of the C-terminal epitome of preproenkephalin-A: Met-enkephalin-Arg⁶-Phe⁷-OH in this secreted high-molecular-weight zone suggest that the ≈8500-Da form of BAM-22P is the C-terminal of preproenkephalin A.