Expression of G protein-coupled receptor 30 in the spinal somatosensory system.
Estrogens were originally identified as the primary sex steroid hormones in females and regulators of reproductive function and sexual behavior, but it has long been suggested that estrogens also have local effects on the somatosensory system at the spinal cord level. It is well known that the effects of estrogens are mediated by nuclear estrogen receptors (ERs) through genomic action, but recently a membrane-bound G protein-coupled receptor, GPR30, was identified as a non-genomic estrogen receptor. In this study we investigated the presence and localization of GPR30 in the rat spinal cord and dorsal root ganglion (DRG) in comparison with ERalpha. Using immunohistochemistry and in situ hybridization, we showed the expression of GPR30 in DRG neurons in male and female rats at mRNA and protein levels without specific sexual difference. A dense accumulation of GPR30 immunoreactivity was observed in the outer layer of the spinal dorsal horn, and selective spinal dorsal rhizotomy revealed that GPR30 was transported from the DRG to terminals located in the spinal dorsal horn. GPR30 expression was downregulated in DRG neurons of ovariectomized female rats. The spinal somatosensory system might be modulated by estradiol via putative membrane ER, GPR30-mediated mechanism.
Takanami
Keiko
K
Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Sakamoto
Hirotaka
H
Matsuda
Ken-Ichi
K
Hosokawa
Koji
K
Nishi
Mayumi
M
Prossnitz
Eric R
ER
Kawata
Mitsuhiro
M
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D008297:Male; D009842:Oligopeptides / Q000378:metabolism; D010052:Ovariectomy / Q000379:methods; D021382:Protein Sorting Signals; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D019051:Rhizotomy / Q000379:methods; D011984:Sensory Receptor Cells / Q000378:metabolism*; D012737:Sex Factors; D013116:Spinal Cord / Q000166:cytology* / Q000378:metabolism
D047628:Estrogen Receptor alpha; D004967:Estrogens; C520305:Gper1 protein, rat; D009842:Oligopeptides; D021382:Protein Sorting Signals; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; C073762:lysyl-aspartyl-glutamyl-leucine; D004958:Estradiol; D015740:Calcitonin Gene-Related Peptide