Nonylphenol, an environmental estrogen, affects voltage-gated K⁺ currents and L-type Ca²⁺ currents in a non-monotonic manner in GH₃ pituitary cells

Toxicol Lett. 2013 Apr 12;218(2):137-43. doi: 10.1016/j.toxlet.2013.01.016. Epub 2013 Jan 31.

Abstract

We have investigated the characteristics of voltage-gated K(+) channels and L-type Ca(2+) channels in GH3 rat pituitary cells and the effects of the xenoestrogen (XEs) nonylphenol (NP) on these ion channel currents. Our results have shown that the lower concentrations (10(-15)-10(-14)M) of NP decreased the amplitudes of voltage-gated K(+) currents (IKv) and activated L-type Ca(2+) currents (ICa-L) by reducing half-activation membrane potentials of activation kinetics curves. However, the higher concentrations (10(-10)-10(-9)M) of NP increased the amplitudes of IKv and inhibited ICa-L by reducing the peak values of ICa-L. Thus, NP affects IKv and ICa-L in an opposite and non-monotonic manner.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / drug effects
  • Animals
  • Calcium / metabolism
  • Calcium Channels, L-Type / drug effects
  • Calcium Channels, L-Type / metabolism*
  • Cell Line
  • Dose-Response Relationship, Drug
  • Electrophysiological Phenomena
  • Environmental Exposure / analysis
  • Estrogens / toxicity
  • Ion Channel Gating / drug effects*
  • Ion Channels / drug effects
  • Ion Channels / metabolism
  • Membrane Potentials
  • Patch-Clamp Techniques
  • Phenols / toxicity*
  • Pituitary Gland / cytology
  • Pituitary Gland / drug effects*
  • Pituitary Gland / metabolism
  • Potassium / metabolism
  • Potassium Channels, Voltage-Gated / drug effects
  • Potassium Channels, Voltage-Gated / metabolism*
  • Rats

Substances

  • Calcium Channels, L-Type
  • Estrogens
  • Ion Channels
  • Phenols
  • Potassium Channels, Voltage-Gated
  • nonylphenol
  • Potassium
  • Calcium