Voltage-clamp experiments by double microelectrode technique in rabbit sinoatrial node cell.

When a man-made strand of the rabbit sinoatrial node (S-A node) was shortened by ligation, the spatial decay of the electrotonic potential decreased and the input impedance increased. A satisfactory voltage clamp was achieved in the small S-A node specimen using the double microelectrode technique (Deck, Kern, and Trautwein, 1964).