DIFFERENTIAL RESPONSIVENESS TO CONTRACTILE AGENTS OF ISOLATED SMOOTH-MUSCLE CELLS FROM HUMAN COLONS AS A FUNCTION OF AGE AND INFLAMMATION

To study the involvement of age and inflammation in motor colonic acti vity in man, contractile responses to CCK, carbachol, and KCl of isola ted colonic smooth muscle cells (SMC) from normal and inflamed human c olons were evaluated; the incidence of sex and smoking on contraction was also analyzed. Contractile responses to the three agonists were si gnificantly lower in tissues with a low degree of inflammation than in tissues with high level of inflammation or normal tissues. This reduc tion in cell responsiveness appears to be nonspecific and nonreceptor mediated. A positive correlation of the contractile responses to the t hree stimulants with the age of patients was observed. In contrast, no association was found between sex, smoking, and cell contraction. In conclusion, contractions of SMC due to CCK, carbachol, and KCl were si gnificantly modified during life; inflammation of the colon led to a l oss of SMC responsiveness.