title: Peptide F (pro-enkephalin fragment): radioimmunoassay, and stress-induced changes in adrenal.
abstract: Utilizing a nine amino-acid (Asp-Glu-Leu-Tyr-Pro-Leu-Glu-Val-Glu) non-enkephalin containing fragment of Peptide F from the pro-enkephalin molecule, a radioimmunoassay was developed. Extraction of bovine, rat, and guinea pig adrenomedullary preparations demonstrated this fragment to be present and apparently partially conserved across species. In rats, acute inescapable foot-shock stress led to a significant decrease of the immunoreactive material in the adrenal medulla. Chronic daily stress for two weeks resulted in an inability of the adrenals to alter F levels upon subsequent stress. The existence of F-like immunoreactivity and its alteration by environmental manipulation, suggest that it may play a unique physiological role.
mesh_terms: D000313:Adrenal Medulla / Q000032:analysis / Q000503:physiopathology*; D000818:Animals; D002417:Cattle; D002837:Chromaffin Granules / Q000032:analysis; D003429:Cross Reactions; D004745:Enkephalins; D006168:Guinea Pigs; D010446:Peptide Fragments / Q000032:analysis*; D011498:Protein Precursors; D011863:Radioimmunoassay; D051381:Rats; D013312:Stress, Physiological / Q000503:physiopathology*
chemical_list: D004745:Enkephalins; D010446:Peptide Fragments; D011498:Protein Precursors; C029992:proenkephalin