Premium
Regulation of bioactive β‐endorphin processing in rat pars intermedia
Author(s) -
Ham J.,
Smyth D.G.
Publication year - 1984
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(84)80778-4
Subject(s) - intermedia , pars intermedia , chemistry , medicine , endocrinology , biochemistry , biology , art , pituitary gland , hormone , performance art , art history
Acid extracts of rat pituitary neuro‐intermediate lobes have been shown by ion‐exchange chromatography and radio‐immunoassay to contain predominantly the inactive derivatives of β‐endorphin, α N ‐acetyl β‐eadorphin 1–27 and α, N ‐acetyl β‐endorphin 1–26; the biologically active form, β‐endorphin 1–31, is a minor component. In contrast, it was found that β‐endorphin generated in neuro‐intermediate lobe cells in monolayer culture was less processed: the principal peptides related to bioactive β‐endorphin 1–31. When the cultured cells were incubated in the presence of 10 −5 M dopamine or 10 −6 M α‐ergocryptine there was a marked increase in the degree of proteolysis and acetylation: the processing pattern reverted to that characteristic of the neuro‐intermediate lobe in situ, with α‐ N ‐acetyl β‐endorphin 1–26 and α, N ‐acetyl β‐endorphin 1–27 as the prominent peptides. The results demonstrate that dopaminergic agents can influence the processing of β‐endorphin‐related peptides in rat pars intermedia, indicating a new level at which the bioactivity may be regulated.