title: Distribution, Isolation and Sequence Analysis of the C-Terminal Heptapeptide of Pro-Enkephalin A (YGGFMRF) from the Ovine Median Eminence.
abstract: Abstract Using a polyclonal antiserum raised against the C-terminal heptapeptide of pro-enkephalin A, we have isolated the opioid heptapeptide Tyr-Gly-Gly-Phe-Met-Arg-Phe (MERF) from ovine median eminence and mapped its distribution in that structure. MERF-immunoreactivity was confined to the pars externa (neurosecretory zone) where it colocalized with corticotrophin-releasing factor in the majority of terminals. No larger, N-terminally extended forms of MERF were detected in median eminence extracts suggesting that pro-enkephalin is fully processed to its constituent enkephalin congeners, and that the bioactive products, including MERF, act at the level of the hypothalamus in regulating anterior pituitary function.
authors.affiliation: Department of Medicine, The University of Melbourne, Western Hospital, Footscray, Victoria 3011, Australia.
authors.forename: A S
authors.initials: AS
authors.lastname: Giraud
authors.forename: I J
authors.initials: IJ
authors.lastname: Clarke
authors.forename: S E
authors.initials: SE
authors.lastname: Rundle
authors.forename: L M
authors.initials: LM
authors.lastname: Parker
authors.forename: J W
authors.initials: JW
authors.lastname: Funder
authors.forename: R J
authors.initials: RJ
authors.lastname: Simpson
authors.forename: A I
authors.initials: AI
authors.lastname: Smith