Abstract
The effect of doxapram, a respiratory stimulant, on the formation of lipid peroxide was investigated in mice. A significant increase of lipid peroxide was observed in the liver after injection of doxapram (100 mg/kg, i.p.) and the level of lipid peroxide was about 5-fold greater than that of control mice at 4 h after injection. However, no increase of lipid peroxide was observed in the brain, heart, lung, spleen or kidney of mice treated with doxapram. On the other hand, doxapram initially increased the activity of xanthine oxidase but significantly reduced it from about 4 h after injection, and also reduced the activities of superoxide dismutase and glutathione peroxidase in the liver. The level of α-tocopherol decreased slightly in the liver after administration of doxapram. This enhancement of lipid peroxidation in the liver in doxapram-treated mice suggests that an increase of superoxide anion and an inhibition of free radical scavenging reactions in vivo may be produced by the drug.
