| Abstract: | It is known that the thymus is severely affected by nutritional deficiency. Adenosine deaminase (ADA) and Purine Nucleoside Phosphorilase (PNP) are thought to be important for normal lymphocyte development. The present paper studies the effect provoked on the activity of these thymic enzymes in growing rats by marginal(PF15), moderate(PF20) and severe(PF25) protein deprivation and the subsequent oral administration of a 20% dietary protein during 9 days (R). Results were expressed as μmol uric acid x 10?1/W, per five minutes, where W = Tw (mg)/Bw(g)0.75. (Mean ± S.D.). Statistical differences between PF15 and Control (C) in: ADA (17.5±4.1 vs. 10.5±2.8), PNP (7.1±0.8 vs. 3.7±0.9); PF20 and C in:, ADA (15.7±4.5 vs. 9.1±3.0), PNP (10.3±4.1 vs. 3.9±1.0); PF25 and C in: ADA (17.0±2.6 vs. 9.1±3.0) and PNP (11.5±4.2 vs. 3.9±1.0) were observed (p< 0.01). When PF25 was refed with a 20% casein diet(R), activity of ADA and PNP decreased significantly when compared to PF25. No statistical differences in ADA and PNP were observed between R and its Control (7.4±2.5 vs. 9.3±1.8; 3.6±0.5 vs. 3.9±0.6, respectively). The results show that protein deprivation at weaning provokes increase in ADA and PNP activities. The refeeding with a 20% protein diet during 9 days is enough to reverse the effect produced by severe protein malnutrition on ADA and PNP activities. |
