Male rats were given a single oral dose of ANIT (100 mg/kg body weight), 5 rats weresacrificed at 24 hours intervals respectively until 144 hours, several examination were carriedout using liver and serum. Strong bile canalicular ALP activity was seen with degeneration of bile ducts andperiductal inflammation later than 24 hours after administration of ANIT, contrasting withnormal rats which showed weak ALP activity. ANIT also elicited cessation of bile flowwith marked elevation of serum bilirubin and serum ALP activity. Peaks of serum and liverextract ALP activities were seen at 48 hours after the beginning of the experiment. ALPzymograms of the serum and liver extract showed marked elevation of hepatic ALP anddecrease in intestinal ALP when serum ALP was high, but in convalescent stage, when bileexcretion returned to normal, increase in intestinal ALP was observed. These results indicated that bile influences upon the activities of hepatic and intestinal ALP.