Changes in electrical potential difference of rectal mucosa and of gallbladder bile constituents of dogs fed chenodeoxycholic acid
Eighteen dogs were studied for 54 days. Rectal mucosal electrical potential difference (PD), gallbladder bile acids, cholesterol, and phospholipids were measured. It was shown that feeding chenodeoxycholic acid (CDCA) for 24 days in dosages of 15, 30, and 60 mg/kg of body weight, all depressed PD equally but significantly (P < 0.05) in three groups of dogs compared with a control group. This depression was reversible 24 days after CDCA ingestion ceased in the two highest dosages. The low dose group was sacrificed after 24 days of CDCA feeding and the gallbladder bile was analyzed. CDCA and cholesterol were each significantly (P < 0.05) elevated over control values in the gallbladder bile of these dogs. Phospholipids were not significantly changed. The PD, a reflection of Na+–K+ ATPase activity, may be a useful indicator in maximizing dosages of CDCA in gallstone dissolution studies.