Involvement of G protein-coupled receptor 30 (GPR30) in rapid action of estrogen in primate LHRH neurons.
Previously, we have reported that 17beta-estradiol (E(2)) induces an increase in firing activity of primate LH-releasing hormone (LHRH) neurons. The present study investigates whether E(2) alters LHRH release as well as the pattern of intracellular calcium ([Ca(2+)](i)) oscillations and whether G protein-coupled receptor 30 (GPR30) plays a role in mediating the rapid E(2) action in primate LHRH neurons. Results are summarized: 1) E(2), the nuclear membrane-impermeable estrogen, estrogen-dendrimer conjugate, and the plasma membrane-impermeable estrogen, E(2)-BSA conjugate, all stimulated LHRH release within 10 min of exposure; 2) whereas the estrogen receptor antagonist, ICI 182,780, did not block the E(2)-induced LHRH release, E(2) application to cells treated with pertussis toxin failed to induce LHRH release; 3) GPR30 mRNA was expressed in olfactory placode cultures, and GPR30 protein was expressed in a subset of LHRH neurons; 4) pertussis toxin treatment blocked the E(2)-induced increase in [Ca(2+)](i) oscillations; 5) knockdown of GPR30 in primate LHRH neurons by transfection with small interfering RNA (siRNA) for GPR30 completely abrogated the E(2)-induced changes in [Ca(2+)](i) oscillations, whereas transfection with control siRNA did not; 6) the estrogen-dendrimer conjugate-induced increase in [Ca(2+)](i) oscillations also did not occur in LHRH neurons transfected with GPR30 siRNA; and 7) G1, a GPR30 agonist, resulted in changes in [Ca(2+)](i) oscillations, similar to those observed with E(2). Collectively, E(2) induces a rapid excitatory effect on primate LHRH neurons, and this rapid action of E(2) appears to be mediated, in part, through GPR30.
Noel
Sekoni D
SD
Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, Wisconsin 53715-1299. terasawa@primate.wisc.edu.
Keen
Kim L
KL
Baumann
David I
DI
Filardo
Edward J
EJ
Terasawa
Ei
E
D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects; D002478:Cells, Cultured; D050091:Dendrimers / Q000494:pharmacology; D004622:Embryo, Mammalian; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology*; D004966:Estrogens, Conjugated (USP) / Q000494:pharmacology; D005260:Female; D000077267:Fulvestrant; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D008253:Macaca mulatta; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D009833:Olfactory Pathways / Q000187:drug effects / Q000378:metabolism; D037342:Pertussis Toxin / Q000494:pharmacology; D011247:Pregnancy; D011323:Primates / Q000378:metabolism / Q000502:physiology; D034741:RNA, Small Interfering / Q000494:pharmacology; D043562:Receptors, G-Protein-Coupled / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects
D050091:Dendrimers; D004966:Estrogens, Conjugated (USP); D034741:RNA, Small Interfering; D043562:Receptors, G-Protein-Coupled; C043090:estradiol-bovine serum albumin; D000077267:Fulvestrant; D012710:Serum Albumin, Bovine; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D037342:Pertussis Toxin