In-vitro studies of gallstone dissolution: the effect of added heparin in bile salt solutions.

The dissolving effect of four bile salt solutions (sodium cholate, sodium taurocholate, sodium deoxycholate and sodium chenodeoxycholate) upon gallstones was tested in an in-vitro preparation, using 226 stones from 38 patients. The effect of each solution was measured by recording weight loss in the gallstone at the end of a ten-day period of immersion in the bile salt solution. Sodium deoxycholate and sodium chenodeoxycholate produced the greatest average weight loss in the groups of stones tested with pure bile salt solutions, but the addition of heparin to solutions of sodium cholate and sodium deoxycholate produced a significant increase in weight loss in these solutions. This effect of heparin in the presence of bile salts, in comparison with the failure of heparinized saline to induce weight loss in gallstones, is discussed. Sodium chenodeoxycholate cannot be recommended for clinical use on the grounds of its toxicity, and in view of the possible toxicity of sodium deoxycholate it is concluded that a combination of sodium cholate with heparin is the optimum solution for the dissolution of retained intraduct calculi in vivo.