Figure 7. Chronotropic effect of acetylcholine and isoproterenol.
Histogram in panel A summarizes the effects of acetylcholine (ACh) and isoproterenol (Iso) on AP parameters. Representative examples of the AP response to both agonists are shown in B. Panel C summarizes changes in beat-to-beat CL variability on a subgroup of n = 8 cells which underwent both treatments sequentially.