[Relation between pigment gallstone formation and the ability of bile to scavenge superoxide radicals].

Operative stenosis of common bile duct (CBD) (S group) induced pigment gallstones in 14 of 16 guinea pigs one week after operation. If Vit E and Vit C were given intraperitoneally 10 mg/kg daily from 3 days before to one week after the operation (S+V group), the gallstone incidence decreased to 5/14 (P < 0.01). In comparison with control group (C), unconjugated bilirubin (UCB) and Ca2+ concentration in gallbladder bile of S group increased significantly (P < 0.05 and P < 0.01 respectively), while the scavenge rate (SR) of superoxide radical (O2-.) in bile decreased significantly (P < 0.05). Comparing S+V group with S group showed that the differences of UCB and Ca2+ concentration were not significant (P < 0.05 both); only the SR rose significantly (P < 0.05) and reached the level of C group. It is suggested that besides the increase of UCB and Ca2+ concentration, the participation of oxygen radicals may be needed in formation of pigment gallstones induced by bile duct obstruction.