Figure 2.

Inhibition of heteromeric Kv7.2/7.3 channels by the muscarinic agonist oxotremorine-M (Oxo-M). The channels were expressed in Chinese Hamster Ovary cells by KCNQ2 and KCNQ3 cDNA transfection. (A) Inhibition of whole-cell current recorded with a perforated patch electrode. Currents were generated by depolarizing the cell to −20 mV; records show deactivation of this steady outward current by 1 s hyperpolarizing steps to −50 mV. (B) Equivalent multi-channel activity recorded within a cell-attached membrane patch is inhibited by applying Oxo-M to the solution bathing the cell outside the patch, thereby activating muscarinic receptors remote from the Kv7.2/7.3 channels (‘remote inhibition’). (From Selyanko et al., 2000).