Enhanced formation of ethane and n-pentane by rat hepatocytes in the presence of dimethyl sulfoxide

Abstract

Incubation of rat hepatocytes with 14 mM dimethyl sulfoxide (DMSO) produced an increase in the formation of ethane, measured by capillary column gas chromatography, to 18.0 pmoles/hr/10 7 cells from 11.2 pmoles/hr/10 7 cells in control hepatocytes, and an increase in the formation of n-pentane to 17.5 pmoles/hru/10 7 cells from 5.6 pmoles/hr/10 7 cells in control hepatocytes. This was about one-third the stimulation of ethane and n-pentane formation produced by incubation of hepatocytes with 13 mM carbon tetrachloride. DMSO-stimulated ethane and n-pentane formation was inhibited up to 63% by 0.1 μM α-tocopherol and up to 89% by N 2. Formation of dimethylsulfide from DMSO by hepatocytes was the same in air and N 2. DMSO increased methane production by hepatocytes to 31.3 pmoles/hr/10 7 cells from 6.9 pmoles/hru/10 7 cells in control hepatocytes. Although DMSO apparently stimulated lipid peroxidation by hepatocytes, as measured by ethane and n-pentane formation, there was no increase in the formation of thiobarbituric acid reactive material. DMSO was not toxic to hepatocytes, measured by release of cytosolic lactate dehydrogenase, over a 2-hr incubation. Possible mechanisms for the increase in alkane formation by DMSO are discussed.