Effects of vincristine on the bile flow in male albino rats

Bile secretion is an important function served by the liver. The microtubular system integrity plays a key role in hepatic transport and excretion of several of bile constituents including phospholipids & cholesterol as well as detoxified xenobiotics. Furthermore, an alteration in bile secretion has been proposed as an important cause of enteritis, also a complication of microtubular inhibitors like Vincristine (VCR) that may occur following treatment as an anti cancer drug. The study aims to study the effects of microtubule inhibitor VCR on bile flow and bile composition in rats. For this purpose, male albino rats were studied. One group of five rats was infused with single IV dose of VCR (@1 mg/kg and the other received equal volume of IV vehicular fluid. For bile samples, animals were cannulated, bile flow examined at different time intervals before and after drug administration. Biliary composition studied at second hour post i/v administration. Single dose VCR treatment showed significant rise in the baseline excretion of bile in animals studied during first 2 hrs, although, there was a mild reduction in the biliary flow rate after few hours. Biliary total cholesterol was decreased and cation concentrations increased significantly in the second hour post VCR. The results indicate that the exposure of rats to VCR induces early alterations in biliary secretion. This study may prove useful for the purpose of understanding enteritis in patients undergoing chemotherapy.