Microelectrode array (MEA) analysis of ion channels controlling spontaneous chromaffin cells electrical activity

A 60 MEA system (MCS GmbH, Reutlingen, Germany) was used for recording spontaneous action po-tentials from rat chromaffin cells (RCCs). The results obtained were compared with the intracellular ac-tion potential recorded in perforated patch clamp experiments with the aim of: 1) monitoring the spontaneous electrical activity by means of extracellular recording and, 2) identifying the role of ion chan-nels controlling action potential firings by analyzing the changes of extracellular recordings induced by selective ion channel blockers. Preliminary analysis of spontaneously active RCCs revealed the existence of strict correspondence between extracellular MEA signals and intracellular action potential recordings, making the MEA system a valuable tool for studying the functional role of ion channels in cell excitability.