Characterization of rat pituitary cells by their responses to hypothalamic releasing hormones.
Rat pituitary cells in monolayer culture were characterized by their [Ca2+]i responses to hypothalamic releasing hormones, growth hormone (GHRH), thyrotropin-releasing hormone (TRH), gonadotropin-releasing hormone (GnRH) and corticotropin-releasing hormone (CRH). The percentages of the cell population responding to GHRH, TRH, GnRH, CRH and non-responding cells were 27.3%, 47.6%, 13.8%, 6.2% and 35.3%, respectively. Some of the cells responded to two or more of those hormones. In the GHRH-responding cells, the population of TRH-responding cells was 51.4%, In the TRH-responding cells, the population of GHRH-responding cells was 30.8%. Some of the GHRH-responding cells also responded to CRH and GnRH. In the GnRH-responding cells, the population of TRH-responding cells was 61.8%. In summary, GHRH-responding cells have an especially close relationship with TRH-responding cells, and GnRH-responding cells also have close relationship with TRH-responding cells. There is also some relationship between the populations responding to other pairs of releasing hormones. These findings suggest functional overlapping among each population of pituitary cells.
Kasahara
K
K
Department of Obstetrics and Gynecology, Osaka University Medical School, Japan.
Tasaka
K
K
Masumoto
N
N
Mizuki
J
J
Tahara
M
M
Miyake
A
A
Tanizawa
O
O
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D013007:Growth Hormone-Releasing Hormone / Q000494:pharmacology*; D007700:Kinetics; D010902:Pituitary Gland / Q000187:drug effects* / Q000378:metabolism; D010906:Pituitary Hormone-Releasing Hormones / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology
D010906:Pituitary Hormone-Releasing Hormones; D007987:Gonadotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone; D003346:Corticotropin-Releasing Hormone; D013007:Growth Hormone-Releasing Hormone; D002118:Calcium