Investigation of the dose-response relationship upon intraperitoneal administration of coumarin and 7-hydroxycoumarin on the carrageenan induced edema of the rat hind paw.

The dose-response relationship upon intraperitoneal administration of coumarin (C) and 7-hydroxycoumarin (7HC) in rats was evaluated using the carrageenan induced edema of the hind paw. In a preliminary study C was indicated to reduce the 4-h edema at doses of 10 to 60 mg/kg i.p. Doses of 2.5 and 5 mg/kg were not effective. In the same study 7HC did not appear to be effective over a dose range of 0.01 to 20 mg/kg. A second study based on a completely randomized design indicated 7HC to be ineffective at doses of 2.5, 5, 10 and 20 mg/kg for edema measurements made at 3, 4, 5 and 6 h after the injury stimulus. C, however, was found to be effective at doses of 5, 10 and 20 mg/kg at 3, 4 and 5 h. C dose of 2.5 mg/kg was ineffective at all times and the 20 mg/kg dose appeared to be ineffective at the 6-h measurement. Resolution of the edema after 5 h did not appear to be enhanced by either C or 7HC administration as the rate of decay appeared to be parallel for controls and the treated animals. The edema model used here would possibly be very useful for further pharmacological investigation of the benzopyrones due to its simplicity, reproducibility and speed.