Possible Interaction: Ethanol and Urethane

“Previous studies from this laboratory have demonstrated that ethanol , in vivo, inhibits the metabolism of ethyl carbamate in mice, but the enzyme system has not been identified.”

“At concentrations similar to those in wine, ethanol inhibits the tissue distribution of urethane in mice.”

“In male mice a different relationship was observed: ethanol caused a dose-related decrease in alveolar/bronchiolar and harderian gland adenoma or carcinoma in mice administered 30 ppm urethane.”

“This may be due to ethanol decreasing the first-pass clearance of urethane , thus, increasing systemic distribution.”

“Urethane induced an increase of micronucleated PCE (MN PCE) frequency from 0.…, followed by a decrease to 6.98% at 48 h. When urethane … ethanol , the MN PCE frequency was suppressed to 0.49% at 24 h, …. This delay of MN PCE occurrence indicated that ethanol inhibition was transient.”

“Although these data are still preliminary, they appear to suggest that ethanol may inhibit formation of DNA adducts by urethane.”

“Alveolar/bronchiolar adenomas occurred in four males and one female administered urethane in ethanol. [”

“Coadministration of urethane and ethanol inhibited the clearance of urethane from plasma. (”

“The estrous cycle length of females receiving urethane in ethanol appeared to be longer than that of females receiving urethane in drinking water.”

“The lethal effects of 10,000 ppm urethane were slightly exacerbated by 5% ethanol in female rats.”

“Metabolism of urethane is mediated by multiple pathways, and ethanol is known to inhibit the esterase hydrolysis pathway of urethane , which accounts for over 95% of urethane metabolism.”

“This magnitude of increase was suppressed when urethane was co-administered with ethanol at ethanol doses of 2500 mg/kg and above.”

“This report shows that ethanol also inhibits the induction of micronuclei by urethane in mouse bone marrow erythrocytes, presumably by inhibiting the minor pathway that generates genotoxic metabolite(s).”

“This study shows that ethanol inhibits the induction of micronuclei by urethane.”

“ Ethanol and a variety of other compounds previously have been shown to acutely inhibit the metabolism of ethyl carbamate (EC) when given concurrently in mice.”

“On the other hand, ethanol pretreatment (10% in drinking water for the period 48 to 12 hr prior to EC treatment) is known to have the opposite effect and enhance the clearance of EC from blood of mice.”

“The tumour yields induced by urethane treatment were greatly reduced by simultaneous treatment with ethanol.”

“Paraoxon, carbaryl, CCl4 ethanol , methimazole, 4-methylpyrazole, diethyl maleate, ethyl N-hydroxycarbamate, and t-butyl carbamate inhibit, to different extents, the metabolism of ethyl carbamate in vivo; SKF-525A, CoCl2, Cacyanamide, chloral hydrate, 2-oxo-4-thiazolidine carboxylic acid, allopurinol, and methyl carbamate do not.”

“The metabolism of ethyl carbamate and the localization of its metabolites have been shown to be almost completely inhibited by ethanol in the mouse [Waddell, Marlowe, Pierce: Food Chem.”