Daily fluctuation of cholestatic enzymes in bile and its relationship to the total bile salts concentration.

The activities of alkaline phosphatase (AP), gamma-glutamyl-transpeptidase and leucine aminopeptidase as well as the total bile salt concentration (Tbs) were measured in bile specimens collected spontaneously at 7 and 11 a.m. and 4 and 9 p.m. from the 3rd-9th postoperative day of 16 patients with T-tube insertion. The general trend for all cholestatic enzymes to increase or decrease was in some way related to the total bile salt concentration. The best correlation was found between AP and Tbs (r = 0.48). It is suggested that the enterohepatic circulation of bile salts may lead to the delivery of membrane-bound cholestatic enzymes into the bile canaliculi without damage to the hepatocyte.