Effect of colistin on reduction of biliary flow induced by endotoxin in E. coli

In order to evaluate whether an antiendotoxin agent can inhibit the action of endotoxin of Escherichia coli on biliary flow, we used 18 models of isolated perfused pig liver divided into four groups: (A) five perfused livers (control), (B) five perfused livers with 2 mg/100 ml of endotoxin added, (C) five perfused livers with 2 mg/100 ml of endotoxin added and treated with 1,500,000 IU of colistin, and (D) three perfused livers with 1,500,000 IU of colistin with no endotoxin. The livers were isolated and perfused according to a technique previously described by our laboratory. The viability of the perfusions was controlled by means of the mitochondrial respiration test. Transaminase and LDH levels were measured in the perfused circuit. A significant reduction of the biliary flow was found in the group with endotoxin of Escherichia coli (P less than 0.002). There was no reduction of biliary flow after addition of 1,500,000 IU of colistin (P less than 0.001). No significant changes were observed in the other parameters measured, and no increase of the bile flow was observed in the colistin group. From our results we conclude that colistin is an inhibitor in vitro of the diminished biliary flow induced by endotoxin of Escherichia coli.