[Effect of methionine-5-enkephalin retroanalog on gastric secretion].

Alteration of the enkephalin molecule by means of synthesis of peptide with opposite direction of peptide connections between residues of aminoacids (retro--methionin--5--enkephalin) entailed some changes of its action in respect to activity of the stomach secretory cells in dogs. Thus, for instance, the retroanalogue methionin--5--enkephalin proved to be a more efficient activator of gastric secretion induced with pentagastrin.