Elevated Lipid Peroxidation in Rats Induced by Dietary Lipids and N-Nitrosodimethylamine and its Inhibition by Indomethacin Monitored Via Ethane Exhalation

Abstract

The effect of dietary lipids alone or in combination with an administered carcinogen, N-nitrosodimethylamine (NDMA), on whole body lipid peroxidation was studied in rats in viro. Groups of rats were fed diets containing 2%, 12.5'30, or 25% of either saturated or polyunsaturated fat. Lipid peroxidation in individual animals was determined by measuring the concentration ofethane in exhaled air. Increased ethane exhalation was found in rats when the amount of dietary fat was increased from 2% to 12.5%, but animals receiving 12.5% or 25% fat in the diet exhaled ethane at similar rates. Rats consuming polyunsaturated fat exhaled more ethane than those eating saturated fat. In all groups, NDMA administration drastically increased ethane exhalation. Indomethacin completely blocked the increase in ethane exhalation caused by dietary lipids.at SAGE PUBLICATIONS on December 9, 2012 tpx.sagepub.com Downloaded from

Pharmacokinetic properties of N‐nitrosofenfluramine after its administration to rats

“…The nitrosamine effectively increased lipid peroxidation as determined by measuring ethane in exhaled air. Similarly, lipid peroxidation in the liver increased rapidly after treatment with NDMA (Ahotupa et al ., 1987a, b; Hietanen et al ., 1987). Recently, researchers have tried to elucidate the mechanisms by which nitrosamine compounds cause hepatotoxicity and liver cancer, and have investigated the role of the production of free radicals and their consequences on lipid peroxidation as well as oxidative stress (Muzio et al ., 1999; Bansal et al ., 2000; Grudzinski and Frankiewicz‐Jozko, 2001; Nakagawa et al ., 2006a, b).…”