Secretin, cholecystokinin and the biliary canalicular secretion in the rat.

An attempt has been made to further assess which fraction of bile can be stimulated by the main gastrointestinal hormones in rats. In the cannulated conscious animals the i.v. infusions of glucagon, impure Boots secretin, impure Boots cholecystokinin (CCK) and OP-CCK resulted in 8.9% (N.S.), 68.5% (P < 0.001), 88.7% (P < 0.001) and 19.0% (P < 0.05) increase in the estimated bile acid-dependent bile flow (BAF) and in 25.4% (P < 0.01), 49.2% (P < 0.001), 44.5% (P < 0.001) and 1.6% (N.S.) increase in the estimated bile acid-independent bile flow (BAIF), respectively as compared to the control values. When the calculated BAF values corresponding to the bile acid impurities in Boots secretin and Boots CCK were subtracted from BAF and BAIF values obtained during hormone infusions (the corrected values), the increase in both BAF and BAIF was equal to 38.9% (P < 0.02) and 29.4% (P < 0.02) during Boots secretin infusion and to 61.1% (P < 0.01) and 29.4% (P < 0.02) during Boots CCK infusion, respectively as compared to the control values. It can be suggested that the hormonal impurities in the Boots preparations interacting with the principal hormonal component are able to stimulate BAF in the rat. Further extensive study embracing the interactions of the purified gut hormones may confirm their role in the control of canalicular bile secretion in the rat.