Different distributions of interstitial cells of Cajal and platelet-derived growth factor receptor-α positive cells in colonic smooth muscle cell/interstitial cell of Cajal/platelet-derived growth factor receptor-α positive cell syncytium in mice

Figure 4 Effects of small conductance calcium-activated potassium channel 3 channel antagonist and agonist treatment on smooth muscle contractions in the murine colon. A and C: Responses of colonic migrating motor complexes (CMMCs) to small conductance calcium-activated potassium channel 3 (SK3) channel antagonist treatment in the proximal and distal colon and summary of the CMMC responses to apamin as indicated by the area under the curve (AUC) at 300 s. The data are normalized to the control value (before the application of apamin) (n = 7; ^aP < 0.05 vs control; ^cP < 0.05 vs proximal colon). B and D: Enhanced effects of apamin (300 nmol/L) on spontaneous contractions in the proximal and distal colon and summary of the data showing contractile responses to apamin as indicated by the AUC at 200 s. The data are normalized to control (before the application of apamin) (n = 7; ^aP < 0.05 vs control; ^cP < 0.05 vs proximal colon). E and G: Responses of CMMCs to SK3 channel agonist treatment in the proximal and distal colon and summary of the CMMC responses to CyPPA as indicated by the AUC at 300 s. The data are normalized to the control value (before the application of CyPPA) (n = 7; ^aP < 0.05 vs control; ^cP < 0.05 vs proximal colon). F and H: Inhibitory effects of CyPPA on spontaneous contractions in the proximal and distal colon and summary of the data showing contractile responses to CyPPA as indicated by the AUC at 200 s. The data are normalized to the control value (before the application of CyPPA) (n = 7; ^aP < 0.05 vs control; ^cP < 0.05 vs proximal colon). AUC: Area under the curve.