A proenkephalin A-derived peptide analogous to bovine adrenal peptide E from frog brain: purification, synthesis, and behavioral effects.
A peptide derived from the posttranslational processing of proenkephalin A was isolated from an extract of the brain of the European green frog Rana ridibunda and its primary structure established as: Tyr-Gly-Gly-Phe-Met-Arg-Arg-Val-Gly-Arg10- Pro-Glu-Trp-Trp-Gln-Asp-Tyr-Gln-Lys-Arg20-Tyr-Gly-Gly-Phe-Met. The structure was confirmed by chemical synthesis. The peptide represents an amphibian equivalent of bovine adrenal peptide E [preproenkephalin A (206-230)-peptide] but the sequence contains two amino acid substitutions (Met15-->Gln and Leu25-->Met) compared with the mammalian peptide. The data support previous hypotheses that the Leu-enkephalin sequence is not present in preproenkephalin A of amphibians. Intracerebroventricular injections of frog peptide E (10 and 100 ng) in mice had no significant effect on horizontal locomotor activity. The peptide, in doses up to 1 microgram, had no effect on latency of escape jumping in the hot plate test and the peptide (100 ng) did not modify responses (paw licking, rearing, and escape jumping) in morphine-treated mice.
Conlon
J M
JM
Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178, USA.
Chartrel
N
N
Leprince
J
J
Suaudeau
C
C
Costentin
J
J
Vaudry
H
H
D000311:Adrenal Glands / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001923:Brain Chemistry; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004745:Enkephalins / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D007276:Injections, Intraventricular; D051379:Mice; D008969:Molecular Sequence Data; D011498:Protein Precursors / Q000138:chemical synthesis / Q000302:isolation & purification* / Q000494:pharmacology; D011499:Protein Processing, Post-Translational; D011895:Rana ridibunda; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
D004745:Enkephalins; D011498:Protein Precursors; C029992:proenkephalin; C039933:peptide E (adrenal medulla)