[Effect of cadmium on the microsomal liver enzymes of the rat]

Action of cadmium on microsomal liver enzymes of rat was tested by determination of aniline-hydroxylase and aminopyrine-N-demethylase activities as well as of the cytochrome-P-450 level and measurement of hexobarbital sleep. Rats which had 0.88 mg/kg body weight, 4.4 mg/kg, and 8.8 mg/kg cadmium chloride (CdCl2) orally applied exhibited significant stimulation of aniline-hydroxylase on the first day following application. That stimulation effect remained to be detectable from the group with the highest cadmium dose on the third and even seventh days from application. Aminopyrine-N-demethylase activities were changed by differentiated patterns under the above conditions. Cytochrome-P-450 levels in liver microsomes went down after one single oral application of cadmium chloride. Hexobarbital sleep was prolonged with significance in rats, one day after oral application of 8.8 mg CdCl2/kg body weight. The effects on the above liver enzymes produced by CdCl2 administration in drinking water were identical with those following the above oral application. However, the differences were less strongly pronounced, and hexobarbital sleep was not affected at all.