Effects of glycine on plasma and liver tissue changes of TNF-alpha, ET-1 and nitric oxide contents in rats with obstructive jaundice.

Abstract

To evaluate the effect of glycine on plasma and liver tissue changes of tumor necrosis factor-alpha (TNF-alpha), endothelin-1 (ET-1) and nitric oxide (NO) contents in rats with obstructive jaundice. Ninety healthy Wistar rats of both sexes weighing 275+/-25 g were randomly divided into sham-operated, bile duct-ligated, and bile duct-ligated plus glycine-treated groups, the latter was performed with 5% glycine solution substituting for tap water drunk ad libium for 5 days before and 6 days after operation. Blood and liver tissue were sampled at the time of sacrifice on the 8th day post operation. Plasma total bilirubin, endotoxin, levels, as well as TNF-alpha, ET-1 and NO contents in liver tissue were determined. Plasma endotoxin and total bilirubin levels were significantly higher in both bile duct-ligated and bile duct-ligated plus glycine-treated rats than in sham-operated animals (P=0.000613, 0.00921 and 0.00737, 0.00841 respectively), whereas they did not display any statistically significant difference between the former groups (P=0.417 and 0.374 respectively). Likewise, TNF-alpha, ET-1 and NO contents in both plasma and liver tissue were significantly increased in both bile duct-ligated and bile duct-ligated plus glycine-treated rats compared with sham-operated animals(P=0.00813, 0.00793, 0.00671, 0.00804, 0.00872, and 0.00947 in plasma and 0.00531, 0.00785, 0.00912, 0.00981 and 0.00635 in liver tissue respectively). However, these inflammatory mediators in both plasma and liver tissue were significantly reduced in bile duct-ligated rats fed on 5% glycine solution compared with that without (P=0.00953, 0.00891, 0.0795, 0.00867, 0.0697 and 0.00907 in plasma and liver tissue respectively). Reduction of TNF-alpha, ET-1 and NO contents in plasma and liver tissue of rats fed on glycine may be helpful to alleviate pathological lesions in obstructive jaundice.