Effects of compounds that influence I-K (KCNN4) channels on afterhyperpolarizing potentials, and determination of I-K channel sequence, in guinea pig enteric neurons

Abstract

The late afterhyperpolarizing potential (AHP) that follows the action potential in intrinsic primary afferent neurons of the gastrointestinal tract has a profound influence on their firing patterns. There has been uncertainty about the identity of the channels that carry the late AHP current, especially in guinea pigs, where the majority of the physiological studies have been made. In the present work, the late AHP was recorded with intracellular microelectrodes from myenteric neurons in the guinea pig small intestine. mRNA was extracted from the ganglia to determine the identity of the guinea pig intermediate conductance potassium (I(K)) channel gene transcript. The late AHP was inhibited b..