Figure 7. The decrease in protein expressions of c-kit, ChAT, nNOS and Cx43 in the colon of elderly humans. Expressions of c-kit, ChAT, nNOS and Cx43 proteins in colonic muscle layers detached from youth and older adults were examined by western blotting (n=4 per group), and similar reduction was observed (A-B). The densitometric analysis of protein expressions normalized to β-actin. Statistical analysis was performed using Student’s t-test and data were represented as mean ± SD, statistical significance is: ** P < 0.01, *** P < 0.001 compared with young group.