Effect of antibiotics in the prevention of jejunoileal bypass-induced liver dysfunction.

Administration of antibiotics has been reported to prevent or minimize liver dysfunction in experimental animals having been subjected to jejunoileal bypass, suggesting that jejunoileal bypass-induced liver dysfunction results from production of toxic substances by bacteria in the defunctionalized bowel. However, improved absorption will also prevent bypass-induced liver injury. We studied the effects of tetracycline on the development of bypass-induced liver dysfunction and compared it to the mucosal adaptation of the intact bowel after bypass. After 6 weeks, rats subjected to bypass but not given antibiotics had decreased levels of serum triglycerides, hepatic cytochrome P-450, and hepatic pentobarbital hydroxylase. Evaluation of intestinal mucosal hyperplasia after bypass indicated that animals given antibiotics after bypass developed greater increases in mucosal DNA content, mucosal protein, and mucosal weight than bypassed animals not receiving antibiotics. We speculate that the beneficial effects of antibiotic administration on liver function after bypass may be a result of improved absorption.