title: Nonylphenol, an environmental estrogen, affects voltage-gated K⁺ currents and L-type Ca²⁺ currents in a non-monotonic manner in GH₃ pituitary cells.
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.
authors: Department of Pharmaceutical Toxicology, School of Pharmaceutical Sciences, China Medical University, 92 Beier Road, Heping District, Shenyang 110001, China.
authors: Qinghua
authors: Q
authors: Gao
authors: Tong
authors: T
authors: Zhu
authors: Feng
authors: F
authors: Guo
authors: Shizheng
authors: S
authors: Huang
authors: Huiyuan
authors: H
authors: Hu
authors: Rui
authors: R
authors: Feng
authors: Liying
authors: L
authors: Hao
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000378:metabolism; D020746:Calcium Channels, L-Type / Q000187:drug effects / Q000378:metabolism*; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D055724:Electrophysiological Phenomena; D004781:Environmental Exposure / Q000032:analysis; D004967:Estrogens / Q000633:toxicity; D015640:Ion Channel Gating / Q000187:drug effects*; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism; D008564:Membrane Potentials; D018408:Patch-Clamp Techniques; D010636:Phenols / Q000633:toxicity*; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
chemical_list: D020746:Calcium Channels, L-Type; D004967:Estrogens; D007473:Ion Channels; D010636:Phenols; D024642:Potassium Channels, Voltage-Gated; C025256:nonylphenol; D011188:Potassium; D002118:Calcium