Direct effect of cortistatin on GH release from cultured pituitary cells in the rat.
OBJECTIVE
Cortistatin (CST) is a 17-amino acid neuropeptide expressed mainly in the cortex and hippocampus. It is also found in the peripheral tissues such as the stomach, kidney, pancreas and the immune system. Two forms of cortistatin CST-17, CST-29 bind with high affinity all somatostatin (SS) receptor subtypes. It has been reported that a receptor called MrgX(2) is able to selectively bind both CST-17 and CST-14 rather than SS. In human tissues CST-17 and CST-29, rather than SS, also bind ghrelin receptor GHS-r1a. In in vivo experiments CST inhibited GH and insulin secretion.


OBJECTIVE
The aim of this study was to evaluate the effect of cortistatin on GH release in in vitro experiments.


METHODS
CST-14 and SS-14 in doses of 1nMol, 10nMol, and 100nMol were added after 48 hrs of pituitary cell culture, and the medium was collected 30, 60, 120, 240 min thereafter. rGH was measured with RIA kits provided by Linco.


RESULTS
CST-14 stimulated GH release from cultured pituitary cells in a dose dependent manner. The maximum effect of CST-14 was observed after 60 min of incubation. However, SS-14 in doses of 10 nMol and 100 nMol inhibited GH release.


CONCLUSIONS
A direct stimulating effect of Cortistatin-14 on GH release from cultured pituitary cells was found.
Baranowska
Boguslawa
B
Department of Neuroendocrinology, Medical Centre of Postgraduate Education, Marymoncka 99, 01-813 Warsaw, Poland. zncmkp@op.pl.
Chmielowska
Magdalena
M
Wolinska-Witort
Ewa
E
Bik
Wojciech
W
Baranowska-Bik
Agnieszka
A
Martynska
Lidia
L
D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D013006:Growth Hormone / Q000378:metabolism*; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011863:Radioimmunoassay; D051381:Rats; D011921:Rats, Inbred WKY
D009479:Neuropeptides; C099323:cortistatin; D013006:Growth Hormone