Abstract
This study was designed to investigate the effect of dietary level of $\beta$-carotene on level of antioxidant nutrients of rat tissues. Male Sprague Dawley rats at the age of 30days were fed on diets containing different levels of $\beta$-carotene(0, 10, 120, 1200, 12000mg per kg diet). Body weight gain of rats fed with 12000mg $\beta$-carotene diet was significantly decreased, but liver and heart weights were not significantly different among groups, The content of total glutathione tended to decrease significantly in 12000mg $\beta$-carotene diet group when compared to $\beta$-carotene restriction group(BC O). However, total vitamin C content of liver showed the tendency to increase by $\beta$ -carotene supply up to 1200mg. But this tendency was not found in plasma, The content of zinc in liver and plasma was significantly decreased by $\beta$-carotene restriction. Alkaline phosphatase activity was significantly higher in 12000mg diet group. In case of $\beta$-carotene restriction group, fibroblasts were proliferated in portal endothelium, and the vacuolar size was enlarged more than the nuclear, In 12000mg diet group, hepatic vacuoles were extended, but their size was regular and the lysis of hepatocytes was observed. Also, fibroblasts were proliferated in portal endothelium and the regular vacuolar size was extended.