ACUTE PARACETAMOL INTOXICATION OF STARVED MICE LEADS TO LIPID PEROXIDATION INVIVO

Lipid peroxidation was monitored in female mice in vivo by the measurement of exhalated hydrocarbons. In liver homogenates in vitro lipid peroxidation as determined by malondialdehyde formation, and hepatic total glutathione levels were measured. After a dose of 500 mg/kg i.p. of paracetamol, the hepatic glutathione of fed mice decreased from 61 nmoles/mg liver protein to 30 nmoles/mg, while the animals expired 5 nmoles of ethane/kga · hr. The same dose in starved mice led to a glutathione level of 6 nmoles/mg and an exhalation rate of 125-150 nmoles ethane/kg · hr. In vivo determined and post-mortem in vitro determined lipid peroxidation correlated with a coefficient of 0.66. If hepatic glutathione was depleted to the same extent by administration of diethylmaleate, no significant lipid peroxidation was found. Our findings demonstrate that the drug-induced depletion of liver glutathione leads in vivo to lipid peroxidation, provided that the glutathione level has been diminished by starvation. The data indicate that glutathione depletion alone by other mechanisms does not account for lipid peroxidation. Hence the hepatoprotective role of liver glutathione against drug-induced liver injury has to be reconsidered in detail. This investigation shows a suitable model for such studies. © 1979.