Excretion of malondialdehyde, formaldehyde, acetaldehyde and acetone in the urine of rats following acute and chronic administration of ethanol.

Recent studies have shown that xenobiotics which induce oxidative stress result in an increased production and excretion of acetaldehyde (ACT), formaldehyde (FA), acetone (ACON) and malondialdehyde (MDA) in the urine of rats. We have therefore examined the effect of acute and chronic ethanol administration on the excretion of these four lipid metabolites in female Sprague-Dawley rats. Urine samples were collected over dry ice for 6 hr time periods. Aliquots of urine were derivatized with 2,4-dinitrophenylhydrazine HCl, and extracted with n-pentane. High pressure lipid chromatogrpahy (HPLC) was used to quantitate and the hydrazones of the four lipid metabolite products. Following a single, oral, acute dose of 5 g ethanol/kg, urinary excretion of ACT increased approximately 5.8-fold from 6 to 12 hr posttreatment, and decreased thereafter. FA excretion decreased by approximately 50% from 0 to 12 hr, returned to control values in the 18-24 hr urine samples, and was 1.3-fold greater than control values at 42-48 hr. ACON increased 3.1-fold over control values from 0 to 30 hr and remained elevated throughout the remaining 18 hr of the study. The excretion of MDA increased approximately 1.5-fold from 18 to 36 hr, then remained constant through the 48 hr time point. In a separate series of experiments, a chronic oral dose of 0.5 g ethanol/kg was administered to rats for 10 consecutive days and the urinary excretion of the lipid metabolites MDA, FA, ACT and ACON was examined for 11 days, beginning with the first day of ethanol administration.(ABSTRACT TRUNCATED AT 250 WORDS)