Bioavailability of vitamin A in the rat following ingestion of neomycin sulfate or aluminium hydroxide.
The objective of the present paper was to study the interaction of Neomycin and aluminium hydroxide with vitamin A in terms of the effect of these drugs on the bioavailability of vitamin A in the rat. Bioavailability was determined on the basis of the effects of the drugs on growth and on the plasma and hepatic levels of the vitamin. Vitamin A deficient animals were used in assay 1 and normal animals in assay 2. In each assay the animals were divided into 3 groups: one received Neomycin sulfate (0.1% in the diet), the second received aluminium hydroxide (0.05% in the diet) and the third (control) received no drug. Each of these three groups was subdivided into two groups receiving two different concentrations of vitamin A palmitate. The bioavailability of vitamin A was estimated by the parallel line method from the concentration of vitamin A in the diet and in the liver of the animals. No significant differences in growth or plasma retinol levels were observed between the groups of animals studied in assays 1 and 2. Total vitamin A concentration in the liver of the animals which received Neomycin was lower (p < 0.05) than that observed in the controls. Neomycin reduced the bioavailability of vitamin A by 13.9% (maximum, 18.1% and minimum, 9.6%) in assay 1 and by 13.5% (maximum, 17.7% and minimum, 9.3%) in assay 2. Aluminium hydroxide at the level tested did not affect the bioavailability of vitamin A.
Division of Nutrition, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
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Favaro
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Silva
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Vannucchi
D000536:Aluminum Hydroxide / Q000494:pharmacology*; D000818:Animals; D001682:Biological Availability; D004347:Drug Interactions; D005260:Female; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009355:Neomycin / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014801:Vitamin A / Q000097:blood / Q000378:metabolism*; D014802:Vitamin A Deficiency / Q000378:metabolism; D015430:Weight Gain
D014801:Vitamin A; D000536:Aluminum Hydroxide; D009355:Neomycin