title: Effects of estradiol on high-voltage-activated Ca(2+) channels in cultured rat cortical neurons.
abstract: OBJECTIVE
  Estrogen regulates a wide variety of nonreproductive functions in the central nervous system. Cortical neurons contain a diverse range of voltage-gated ion channels, including calcium (Ca(2+)) channels, and Ca(2+) channels play an important role in the regulation of action potential generation and neuronal excitability. In this study, the effect of estradiol (E2) on high-voltage-activated (HVA) Ca(2+) channels in cultured rat cortical neurons was examined.
  
  
  METHODS
  We used the whole-cell patch-clamp technique to measure the HVA Ca(2+) channels.
  
  
  RESULTS
  We found that HVA Ca(2+) channel currents was inhibited by 17β-E2 in a rapid, reversible and concentration-dependent manner. Moreover, 17β-E2 shifted the steady-state inactivation curve in the hyperpolarizing direction without changing the activation curve. We also found that the inhibitory effects of 17β-E2 on Ca(2+) currents were unaffected by the estrogen receptor (ER) antagonist ICI 182780; however, the protein kinase C (PKC) inhibitor rottlerin and protein kinase A (PKA) inhibitor H-89 blocked the 17β-E2-induced inhibition of Ca(2+) currents.
  
  
  CONCLUSIONS
  E2 inhibited HVA Ca(2+) currents via PKC and PKA-dependent signaling pathway in cortical neurons, and the effects of BPA were independent of classical ER.
authors.affiliation: Department of Preventive Medicine, School of Medical Science and Laboratory Medicine, Jiangsu University , Zhenjiang , China .
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.forename: Qing
authors.initials: Q
authors.lastname: Ye
authors.forename: Rongzhu
authors.initials: R
authors.lastname: Lu
authors.forename: Jie
authors.initials: J
authors.lastname: Cao
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Haixia
authors.initials: H
authors.lastname: Ding
authors.forename: Rong
authors.initials: R
authors.lastname: Gao
authors.forename: Hang
authors.initials: H
authors.lastname: Xiao
mesh_terms: D000818:Animals; D015220:Calcium Channels / Q000502:physiology*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D004958:Estradiol / Q000494:pharmacology*; D047628:Estrogen Receptor alpha / Q000502:physiology; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D009474:Neurons / Q000187:drug effects* / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011247:Pregnancy; D011493:Protein Kinase C / Q000502:physiology; D051381:Rats
chemical_list: D015220:Calcium Channels; D047628:Estrogen Receptor alpha; D004967:Estrogens; D004958:Estradiol; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C