On the mode of action of difenoxin (R 15 403). Part 2: Studies on the perfused isolated colonic loop of the rat (author's transl)]

The effect of 1-(3-cyano-3,3-diphenylpropyl)-4-phenyl-isonipecotinic acid hydrochloride (difenoxin, R 15 403), a new antidiarrhoic agent, was studied in vivo in rats with an isolated colonic loop. Difenoxin had no effect on transport or absorption of fluid during perfusion experiments. When given i.p. it inhibited the motility of the coecum but not that of the colon. Difenoxin has apparently no effect on normal rat colon, although an effect may have been masked by the wide variation of parameters measured under identical conditions.