A STM of the effect of electrical field stimulation (EFS, 10 Hz, 10 sec) on ICC-SS Ca2+ transients in the presence of the muscarinic receptor antagonist atropine (1 μM). B 3-D plots of the effect of EFS (10 Hz, 10 sec) on ICC-SS Ca2+ transients in the presence of atropine. C Summary data of EFS effects in the presence of atropine on the frequency, amplitude, duration and spatial spread of Ca2+ transients, comparing EFS and post EFS periods to pre EFS, c=45, n=10.