Relationship between liver gamma-glutamyltranspeptidase activity and glutathione content in chronic-malnourished pups of adolescent rats

Liver gamma-glutamyltranspetidase (GGT-EC 2.3.2.2) activity and reduced glu tathione (GSH) levels were measured for male pups of adolescent rats on thr ee occasions: delivery day (dl), in the middle of lactation (d10), and afte r weaning (d50). Pups were weaned on the same diets received:by their mothe rs during gestation and up to the 10th day of lactation. Diets varied in pr otein content: 13% and 6% casein. Immediately after birth (dl of lactation) , high levels of enzyme activity were observed in all pups, but these level s had sharply decreased by d10. A significant rise in the pups' GGT activit y was produced by protein restriction at dl and d50. GSH was also significa ntly reduced by protein deprivation at dl and d50. A clear interrelationshi p between liver GGT activity and GSH content could only be established for 50 day-old rats. These results indicate that chronic protein malnutrition e xerts a special influence on both parameters in the growth period after wea ning. (C) 1999 Elsevier Science Inc.