Effects of carbon tetrachloride-induced chronic liver damage on glutathione and glutathione-dependent enzymes in rat gastric mucosa.

The present study investigated the relationship between the concentration of the reduced form of glutathione (GSH) and GSH-dependent enzyme activities in the gastric mucosa during chronic liver injury caused by carbon tetrachloride (CCl4) in rats. There were significant decreases in the mucosal GSH concentration and glutathione S-transferase (GST) activity as well as a significant increase in gamma glutamyltransferase (GGT) activity in rats exposed to CCl4 (all p < 0.001). However, no significant change was observed in glutathione peroxidase (GSH-Px) activity. A negative correlation was seen between the mucosal GSH concentration and GGT activity (p < 0.05) and a positive correlation between the GSH concentration and GST activity (p < 0.01). No correlation was noted between the GSH concentration and GSH-Px activity. Gastric mucosal damage, as evaluated by macroscopic observation and light microscopy, was more damaged in the rats exposed to CCl4 than in the control group. There was a significant correlation between histologic mucosal damage and GGT activity (p < 0.05) as well as a negative correlation between the number of macroscopic lesions and GSH and between the number of macroscopic lesions and GST (p < 0.01). From the observed abnormalities of GSH and GSH-dependent enzymes in the gastric mucosa of the rats exposed to CCl4, GSH content and the activities of GSH-dependent enzymes might play a role in the gastric mucosal defense mechanism during chronic liver injury.