Bisphenol A and 4-tert-Octylphenol Inhibit Cx46 Hemichannel Currents
Bisphenol A and 4-tert-Octylphenol Inhibit Cx46 Hemichannel Currents
- Seunghoon Oh
- 대한생리학회-대한약리학회
- The Korean Journal of Physiology & Pharmacology
- 제19권 제1호
- 등재여부 : KCI등재
- 2015.01
- 73 - 79 (7 pages)
Connexins (Cx) are membrane proteins and monomers for forming gap junction (GJ) channels. Cx46 and Cx50 are also known to function as conductive hemichannels. As part of an ongoing effort to find GJ-specific blocker(s), endocrine disruptors were used to examine their effect on Cx46 hemichannels expressed in Xenopus oocytes. Voltage-dependent gating of Cx46 hemichannels was characterized by slowly activating outward currents and relatively fast inward tail currents. Bisphenol A (BPA, 10 nM) reduced outward currents of Cx46 hemichannels up to ∼18% of control, and its effect was reversible (n=5). 4-tert-Octylphenol (OP, 1 μM) reversibly reduced outward hemichannel currents up to ∼28% (n=4). However, overall shapes of Cx46 hemichannel current traces (outward and inward currents) were not changed by these drugs. These results suggest that BPA and OP are likely to occupy the pore of Cx46 hemichannels and thus obstruct the ionic fluxes. This finding provides that BPA and OP are potential candidates for GJ channel blockers.