© 1990 Oxford University Press
research-article |
Potentiation of CCl4 and CHCl3 Hepatotoxicity and Lethality by Various Alcohols1
Department of Pharmacology and Toxicology, University of Mississippi Medical Center Jackson, Mississippi 39216-4505
Received October 16, 1989; accepted April 26, 1990
Potentiation of CCl4 and CHC13 Hepatotoxicity and Lethality by Various Alcohols. RAY, S. D., AND MEHENDALE, H. M. (1990). Fundam. Appl. Toxicol. 15, 429–440. Various aliphatic alcohols potentiate the toxicity of a wide range of xenobiotics including several haloal-kanes. The present series of experiments were designed to test: (i) whether a single subtoxic dose of alcohol can potentiate CCl4, and CHCl3 hepatotoxicity, and (ii) whether this potentiation leads to greater animal lethality. Selected members of a homologous series of straight chain alcohols were chosen for this study. Methanol, ethanol, isopropanol, t-butanol, pentanol, hexanol, octa-nol, decanol, and eicosanol at equimolar doses (10 mmol/kg) were tested in the present investigation. Each alcohol was administered orally to male Sprague-Dawley rats (175–250 g) 18 hr prior to a single oral administration of CCl4 or CHCl3. Liver injury was assessed by plasma transaminases (alanine aminotransferase, ALT; aspartate aminotransferase, AST) and histopathological examination of liver sections 24 hr after the halomethane treatment. None of these alcohols alone increased plasma ALT or AST significantly, whereas CCl4or CHCl3 administration to alcohol-treated animals resulted in significant elevation of plasma transaminases. Eicosanol (20-carbon alcohol) did not potentiate the toxicity of either halomethane. Methanol, ethanol, isopropanol, and decanol in combination with CCl4 caused massive liver damage but failed to augment CCl4 lethality. t-Butanol, pentanol, hexanol, and octanol significantly decreased the LD50 of CCl4. The hepatotoxic effects of CHCl3 were potentiated by all of the alcohols and the LD50s were also decreased significantly. On a comparative basis, alcohol-potentiated CHCl3 toxicity was greater than the toxicity of CCl4. These findings indicate that even though halomethane liver injury might be potentiated by alcohols, the underlying mechanisms differ among alcohols since not all alcohols potentiate the lethal effects of these halomethanes.