F. Martinezrodenas et al., CIRCULATING BILE IS THE MAIN FACTOR RESPONSIBLE FOR ATRIAL-NATRIURETIC-PEPTIDE RELEASE IN EXPERIMENTAL OBSTRUCTIVE-JAUNDICE, British Journal of Surgery, 85(4), 1998, pp. 480-484
Background Biliary obstruction in the rabbit causes increased release
of atrial natriuretic peptide (ANP). Circulating bile, raised biliary
pressure or absence of bile in the duodenum may be implicated in this
hepatocardiac syndrome. Methods An experimental model was developed to
elucidate the mechanism linking obstructive jaundice and increased pl
asma ANP. Hepatic and renal function, biliary tree pressure and ANP pl
asma concentrations were investigated in conscious rabbits 4 and 24 h
after common bile duct ligation, biliovenous shunting or external drai
nage via a biliary fistula. Results Bilirubin concentration increased
after bile duct ligation and creation of a biliovenous shunt. Plasma c
reatinine increased abruptly in rabbits with a biliovenous shunt. At 4
h, the ANP increase in animals with a biliovenous shunt was ninefold
that observed after bile duct obstruction while no change was noted af
ter external biliary diversion (mean 350 versus 45 versus 9 fmol/l; P
< 0.01). Relief of biliary tree obstruction was associated with a retu
rn of ANP levels towards basal normal values. Conclusion Raised plasma
ANP in obstructive jaundice is not the result of an increased biliary
pressure per se or absence of bile in the proximal duodenum but of th
e passage of bile components to the circulation.