Studies on the Disposition and Metabolism of Hydrazine in Rats in vivo

Abstract

1 Rats were given various doses of hydrazine orally and their plasma and liver hydrazine levels were determined (at various times up to 270 min after dosing) by gas chromatography/ mass spectrometry.

2 The increase in the peak plasma level and in the area under the plasma concentration-time curve (AUC) were not directly proportional to the dose.

3 The ratio of plasma to liver hydrazine varied with dose suggesting saturation of an uptake mechanism might be occurring.

4 In a separate experiment hydrazine was still detectable in the plasma and liver 24 h after dosing with hydrazine i.p.

5 Rats were given the same doses of hydrazine and urine was collected for 24 h after dosing and assayed for hydrazine and acetylhydrazine. The proportion of hydrazine and acetylhydrazine excreted declined with dose.

6 Liver samples were taken for histopathological examination 96 h after dosing. Only after the highest dose (81 mg kg^-1) was there evidence of fatty liver, 96 h after a single dose, and a reduction in both liver and body weight.