[Biotransformation and toxicity of xenobiotics in various routes of administration of vitamin A into the rat body].

Deficiency of vitamin A in rats caused a decrease in metabolic rate of acetanilide as well as in elimination of voltaren from blood plasma, while excess of the vitamin (3,000 IU/kg) stimulated voltaren elimination and increased excretion with urine of aminophenol conjugates of acetanilide with sulfuric and glucuronic acids. Under conditions of vitamin A deficiency formation of acetanilide toxic metabolites was increased as a result of which excretion of mercapturic acids with urine was elevated but excess of vitamin A and its hyperdose inhibited these reactions. At the same time, deficiency of vitamin A amplified the paracetamol and voltaren toxicity and its excess exhibited protective effects.