Rice and bean diets increase hepatic and plasmatic activity of gammaglutamyltranspeptidase in growing rats.

The effect of feeding rice and bean diets in both hepatic and plasmatic act ivity of gamma-glutamyItranspeptidase-(GGT-EC 2.3.2.2) activity was evaluat ed in growing-rats (Experiment A) and mature rats (Experiment B). During 28 days, the animals were fed with isocaloric-diets composed by tree levels o f rice, bean or rice-and-bean protein. Similarly with the aproteic group, a significant increase on both the hepatic and plasmatic GGT activity were s howed with the lowest leves of protein, when compared with 25% casein contr ol group. This rise was more effective in growing-rats fed on legume-based diets (as bean or rice-and-bean diets), making evident a differential effec t of age and an exacerbated effect of the protein restriction with the lowe st sulfur amino acids disposal. These alterations suggest a metabolic adapt ation of GGT to both the inadequate protein and sulfur-amino acid levels, t hus supporting the hypothesis that the Glutathione levels may be reduced by these legume-based diets.