과량의 비타민 E 첨가 및 β-Carotene 대치 식이가 흰쥐의 혈청과 조직의 비타민 E와 A수준에 미치는 영향 = Effects of Supplementation of Vitamin E and Substitution of Beta-Carotene for Retinyl Palmitate in the Diet on Serum and Tissue Levels of Vitamin E and A in Rats

다국어 초록 (Multilingual Abstract)

The present experiment was carried out to study the effect of the supplementation of dietary vitamin E (1000mg/kg diet) and the substitution of beta-carotene for retinyl palmitate (1200R.E/kg diet) on serum and tissue(liver and brain) levels of vitamin E and A in rats(initial body weight: 55∼75 g-younger; 135∼155 g-older rats).
The increase in serum vitamin E levels observed by excess dietary vitamin E supplementation was not seen when beta-carotene was substituted for retinyl palmitate. Serum vitamin A concentration was maintained at rather constant levels during vitamin E supplementation and beta-carotene substitution. Liver vitamin E concentration was affected similarily to serum vitamin E concentration in response to dietary vitamin E supplementation. Liver vitamin A concentration tended to decrease in all vitamin E supplemented groups, especially in the beta-carotene substituted group of the older rats.
Brain tissue differed from other tissues in that its vitamin E and A concentrations showed no significant difference whether vitamin E was supplemented or beta-carotene was substituted. Brain Vitamin E as well as vitamin A concentrations were found to exist mainly in esterified or some other tightly-bound form, but in much lower concentration of Vitamin A than Vitamin E.
The mechanism of the action of beta-carotene on Vitamin E and A should be pursued in more detail at various levels including absorption, conversion to retinol, storage, and breakdown. Further investigation is also needed to clarify the metabolism of Vitamin E and A with respect to esterified and free forms in various tissues especially in the brain and in different animal species. Since Vitamin E and beta-carotene intake is currently increasing among the general public, it is important to clarity the interrelationships between these Vitamins in the body.