Mice were fed basic diet or basic diet plus vitamin E 50 mg or 500 mg per kg of diet for 4 weeks. The animals were killed at 6 or 14 days after one exposure to 400 rad X-ray whole body radiation and the number of lymphocytes of spleen and thymus and blastogenic responses of splenocytes were tested. The results showed; (1) the number of lymphocytes both in spleen and thymus were significantly decreased in mice fed basic diet in com-parision with that in mice fed with basic diet plus vitamin E (P

Semi-purified diets containing 30 ppm or 500 ppm dl-?-tocopherol (VE) were fed for 8 weeks to young (3 months) and old (18 months) Swiss mice. The blastogenic response of splenocytes as well as serum VE and lipid peroxides (LPO) in livers were measued. The results showed that the old mice fed 500 ppm VE had a significantly higher serum VE level and blastogenic response of splenocytes to Con A and LPS than those fed 30 ppm VE (p