SOLID‐PHASE SYNTHESIS OF PORCINE VASOACTIVE INTESTINAL PEPTIDE

Abstract

The 28-residue sequence of porcine vasoactive peptide (VIP) was assembled on a benzhydrylamine resin support, cleaved by HF treatment, and purified by ionexchange and partition chromatography. In addition to the normal criteria, the homogeneity of the final material, obtained in 16% yield, was assessed by reversephase high performance liquid chromatography and the isolation and examination of cyanogen bromide cleavage fragments by the same technique. The purified VIP possessed characteristic inhibitory effects on pentagastrin-induced gastric acid release in the dog. Upon storage, even as the lyophilized powder in vacuo, HPLC revealed the slow formation of a contaminant possibly representing deamidated peptide.