Figure 4

(a) Schematic showing the placement of needle electrodes. (b) Isolated innervated rabbit heart mounted to the working heart system. A pair of needle electrodes is placed close to the superior cardiac branch (cathode) and cranial to the cervical VN (anode). ECG leads were placed into the right atrium for heart rate detection. cr cranial, cd caudal, CB cardiac branch, ECG electrocardiogram, VN vagus nerve.