Glucose ameliorates the depletion of NADPH by paraquat in rat lung slices

Abstract

Paraquat-stimulated NADPH depletion in rat lung slices is responsive to exogenous glucose concentration. Lung slices incubated with 11 mM glucose and 10 −4 M paraquat had a 40% lower NADPH/NADP + ratio than did control lung slices. Incubation with no added glucose and 10 −5 M paraquat caused a 41% decrease in NADPH/NADP +. With paraquat at 10 −5 M, glucose at 1.1, 5.5, 11, or 22 mM increased NADPH/NADP + ratios in a concentration-dependent manner until, at 22 mM glucose, the effect of paraquat was prevented. The sum of NADP + plus NADPH was only 60% of control with 10 −5 M paraquat and no glucose. However, with any concentration of glucose from 1.1 to 22 mM, the total was 92% of control. The results indicate that glucose may be beneficial in preventing paraquat-mediated NADPH depletion in rat lung slices.