[A simple method of isolation and identification of P cells in rat sinoatrial node].

A method of isolating P cells of rat sinoatrial node by collagenase is described. The method is feasible for morphological and electrophysiological investigation, with the advantages of taking a relatively easy procedure and consuming a small amount of collagenase. The main features of action potentials of these isolated cells including clear diastolic automatic depolarization, mean maximal diastolic potential of -55 mV, mean peak potential value of 58 mV, and mean APD50 of 18 ms, were similar to those of P cells in situ.