Intracellular bicarbonate regulates action potential generation via KCNQ channel modulation.

摘要: Bicarbonate (HCO3−) is an abundant anion that regulates extracellular and intracellular pH. Here, we use patch-clamp techniques to assess regulation of hippocampal CA3 pyramidal cell excitability by HCO3− in acute brain slices from C57BL/6 mice. We found increasing levels enhances action potential (AP) generation both the soma axon initial segment (AIS) reducing Kv7/KCNQ channel activity, independent pH (i.e., at a constant 7.3). Conversely, decreasing leads attenuation AP firing. show interferes with activation phosphatidylinositol-4,5-biphosphate. Consequently, propose that, even presence local depolarizing Cl− gradient, efflux through GABAA receptors may ensure inhibitory effect axoaxonic cells AIS due channels.