TY - JOUR
T1 - Expression of G protein-coupled receptor-30, a G protein-coupled membrane estrogen receptor, in oxytocin neurons of the rat paraventricular and supraoptic nuclei
AU - Sakamoto, Hirotaka
AU - Matsuda, Ken Ichi
AU - Hosokawa, Koji
AU - Nishi, Mayumi
AU - Morris, John F.
AU - Prossnitz, Eric R.
AU - Kawata, Mitsuhiro
PY - 2007/12
Y1 - 2007/12
N2 - The regulatory actions of estrogens on magnocellular oxytocin (OT) neurons of the paraventricular and supraoptic nuclei are well documented. Although the expression and distribution of nuclear estrogen receptor-β, but not estrogen receptor-α, in the OT neuron has been described, the nuclear receptors may not explain all aspects of estrogen function in the hypothalamic OT neuron. Recently a G protein-coupled receptor (GPR) for estrogens, GPR30, has been identified as a membrane-localized estrogen receptor in several cancer cell lines. In this study, we therefore investigated the expression and localization of GPR30 in magnocellular OT neurons to understand the mode of rapid estrogen actions within these neurons. Here we show that, in the paraventricular nucleus and supraoptic nucleus, GPR30 is expressed in magnocellular OT neurons at both mRNA and protein levels but is not expressed in vasopressin neurons. Specific markers for intracellular organelles and immunoelectron microscopy revealed that GPR30 was localized mainly in the Golgi apparatus of the neurons but could not be detected at the cell surface. In addition, the expression of GPR30 is also detected in the neurohypophysis. These results suggest that GPR30 may serve primarily as a nongenomic transducer of estrogen actions in the hypothalamo-neurohypophyseal system.
AB - The regulatory actions of estrogens on magnocellular oxytocin (OT) neurons of the paraventricular and supraoptic nuclei are well documented. Although the expression and distribution of nuclear estrogen receptor-β, but not estrogen receptor-α, in the OT neuron has been described, the nuclear receptors may not explain all aspects of estrogen function in the hypothalamic OT neuron. Recently a G protein-coupled receptor (GPR) for estrogens, GPR30, has been identified as a membrane-localized estrogen receptor in several cancer cell lines. In this study, we therefore investigated the expression and localization of GPR30 in magnocellular OT neurons to understand the mode of rapid estrogen actions within these neurons. Here we show that, in the paraventricular nucleus and supraoptic nucleus, GPR30 is expressed in magnocellular OT neurons at both mRNA and protein levels but is not expressed in vasopressin neurons. Specific markers for intracellular organelles and immunoelectron microscopy revealed that GPR30 was localized mainly in the Golgi apparatus of the neurons but could not be detected at the cell surface. In addition, the expression of GPR30 is also detected in the neurohypophysis. These results suggest that GPR30 may serve primarily as a nongenomic transducer of estrogen actions in the hypothalamo-neurohypophyseal system.
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U2 - 10.1210/en.2007-0436
DO - 10.1210/en.2007-0436
M3 - Article
C2 - 17872373
AN - SCOPUS:36348947509
VL - 148
SP - 5842
EP - 5850
JO - Endocrinology
JF - Endocrinology
SN - 0013-7227
IS - 12
ER -