Regulation of MSH release from the neurointermediate lobe of Xenopus laevis by CRF-like peptides.
Immunocytochemical studies showed the presence of a fiber system containing a CRF-like peptide in the median eminence and in the neural lobe of the pituitary gland of Xenopus laevis. During in vitro superfusion of neurointermediate lobe tissue, CRF, sauvagine and urotensin I induced a rapid and dose-dependent stimulation of secretion of MSH and endorphin. Tissue of white-background adapted animals displayed a remarkably higher sensitivity to CRF and sauvagine than tissue from animals that were adapted to a black background. During superfusion of isolated melanotrope cells in suspension, it was shown that CRF and sauvagine exerted their effect directly on the melanotrope cell. We therefore conclude that there is morphological and biochemical evidence to consider a CRF-like peptide as a physiological MSH-releasing factor.
Verburg-Van Kemenade
B M
BM
Department of Zoology II, Faculty of Sciences, Catholic University, Niimegen, The Netherlands.
Jenks
B G
BG
Cruijsen
P M
PM
Dings
A
A
Tonon
M C
MC
Vaudry
H
H
D029845:Amphibian Proteins; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000032:analysis / Q000276:immunology / Q000502:physiology*; D000242:Cyclic AMP / Q000502:physiology; D004723:Endorphins / Q000378:metabolism; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism*; D036361:Peptide Hormones; D010455:Peptides / Q000494:pharmacology; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism*; D014579:Urotensins / Q000494:pharmacology; D014982:Xenopus laevis
D029845:Amphibian Proteins; D004723:Endorphins; D036361:Peptide Hormones; D010455:Peptides; D014579:Urotensins; C025727:sauvagine; D009074:Melanocyte-Stimulating Hormones; D003346:Corticotropin-Releasing Hormone; C029676:urotensin I; D000242:Cyclic AMP