The absorption of -tocopherol in the rat. I. the effect of different carriers and different dose levels
Kelleher, J.; Davies, T.; Smith, C.L.; Walker, B.E.; Losowsky, M.S.
International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift für Vitamin- und Ernahrungsforschung. Journal International de Vitaminologie et de Nutrition 42(3): 394-402
1972
ISSN/ISBN: 0300-9831 PMID: 5086645 Document Number: 47051
1. Groups of 6 rats were given labelled vitamin E by stomach tube and faeces were collected daily for 7 days at the end of which the rats were killed. The vitamin was DL- alpha -tocopherol-5-methyl-3H and was dissolved in groundnut oil or suspended in saline with Tween 80 or dissolved in absolute ethanol and mixed with water; in each case the dose was about 3 mu Ci. The mean percentage absorption, judged from recovery of label in faeces, was not significantly different between oil solution and Tween suspension but rats given the suspension retained over 20 times as much label in liver and 30 times as much in kidneys as those given oil. Again, the mean percentage absorption was similar from oil or ethanol suspension, but the rats given the vitamin in ethanol retained more in liver though not in kidneys. When tocopherol in oil was accompanied by a carrier dose of 20 mg unlabelled alpha -tocopherol the percentage of the large dose absorbed was less but the total amount absorbed was greater. In general over 60% of alpha -tocopherol given by mouth was absorbed, but with carrier it was 30%. Tissue levels could not be used to assess absorption.