Figure 7. CaMKII is required for neurogenic inhibition of colon motility.

(A) KN-62 nearly abolished TTX-evoked contractile response in a mouse colon strip. The effect of KN-62 was partially reversible after about 1 hr washout. (B) Bath application of KN-62 also suppressed CCh-induced myogenic contraction in a reversible manner. (C) The inhibitory effect of KN-62 on TTX-induced response was significantly stronger than on CCh-induced contraction. ** p<0.01. (D) Representative Western Blot analysis shows that pretreatment with 3 µM KN-62 for 15 min dramatically decreased the p-CaMKII-IR in the myenteric plexus preparations of mouse colon. The total CaMKII-IR was comparable between tissue preparations with and without treatment with KN-62. β-actin was used as a loading control. (E) Schematic diagram illustrates the neurogenic and myogenic roles of CaMKII in controlling the colonic intestinal motility.