The effect of indoprofen on phenylquinone-writhing and prostaglandin synthesis.

The ability of indoprofen or sodium indoprofen to inhibit phenylquinone-writhing and renal prostaglandin synthesis was determined in mice following a single oral dose of either drug. Male mice (4/group) were treated with 1.5 mg/kg indoprofen or sodium indoprofen. Inhibition of phenylquinone-writhing was determined at 2, 4, 8, 16 and 32 hr post treatment. Animals were sacrificed and blood collected for determination of plasma indoprofen concentration. Kidneys were removed and prepared for determination of renal prostaglandin synthesis by an in vitro technique. Phenylquinone-writhing was significantly depressed by both preparations at 2 and 4 hr post treatment. Sodium indoprofen also significantly depressed writhing at 8 hr post treatment. Renal prostaglandin synthesis, like phenylquinone-writhing, was significantly depressed at 2 and 4 hr after drug treatment. Plasma indoprofen concentration was correlated with both inhibition of phenylquinone-wrighing and inhibition of renal prostaglandin synthesis. When writhes were plotted versus prostaglandin synthesis, a positive correlation was observed suggesting a temporal relationship between inhibition of phenylquinone-writhing and inhibition of renal prostaglandin synthesis.