Fig. 5

Representative examples of the isochronic maps of the ectopic excitation induced by α- and β-adrenoreceptors agonists or postganglionic nerves stimulation in the BALB/c mice pulmonary veins myocardium. Norepinephrine (NE, a), phenylephrine (PHE, b) induced SAP in the region close to the PV mouth, while in response to isoproterenole (ISO) the excitation was initiated both in the PV mouth (c, left) or PV vein (c, right) sites. Postganglionic intracardiac nerves stimulation (PNS) also induced ectopic excitation in the PV mouth region (d left). d, right representative example of the sustained PNS-induced firing. The traces restricted by a black rectangle represented in the bottom of the panel but with higher time resolution. 1, 2, 3: optical AP traces from the sites indicated in d, left. Arrowhead: motion artifacts