17beta-estradiol attenuates alpha, beta-meATP-induced currents in rat dorsal root ganglion neurons.
The effects of 17beta-estradiol on the alpha,beta-me ATP-induced currents were studied on dorsal root ganglion (DRG) neurons using whole-cell recording technique. Three types of currents (transient, sustained or biphasic) were evoked by alpha,beta-me ATP in acutely dissociated DRG neurons. When neurons were pre-incubated with 17beta-estradiol (10-1000 nM) for 4 min, an inhibition of the transient current and the transient component of the biphasic current was observed. In contrast, 17beta-estradiol did not have any significant effect on the sustained current evoked by alpha,beta-meATP. The inhibitory effects were concentration-dependent, reversible and could be blocked by the estradiol receptor inhibitor, ICI 182,780 (1 microM). However, bovine serum albumin-conjugated 17beta-estradiol (17beta-estradiol-BSA, 10 nM) failed to mimic the effects of 17beta-estradiol. 17alpha-estradiol, the inactive isoform, did not have significant effects on alphabeta-meATP-induced currents, either. Sustained currents induced by ATP (100 microM) in nodose ganglion (NG), superior cervical ganglion (SCG) and otic ganglion (OTG) neurons were not affected by 17beta-estradiol. These results suggest that the female gonadal hormone, 17beta-estradiol, might participate in control of pain by modulating P2X3 receptor-mediated events in sensory neurons.
Ma
Bei
B
Department of Physiology, Second Military Medical University, 800, Xiangyin Road, Shanghai, 200433, China. mabei2004@yahoo.com.cn
Rong
Weifang
W
Dunn
Philip M
PM
Burnstock
Geoffery
G
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D005727:Ganglia, Spinal / Q000502:physiology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000502:physiology*; D010146:Pain / Q000503:physiopathology; D051381:Rats; D018048:Receptors, Purinergic P2 / Q000378:metabolism; D058477:Receptors, Purinergic P2X3; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology
D000970:Antineoplastic Agents; C546410:P2rx3 protein, rat; D018048:Receptors, Purinergic P2; D058477:Receptors, Purinergic P2X3; D004958:Estradiol; D000255:Adenosine Triphosphate; C002630:alpha,beta-methyleneadenosine 5'-triphosphate