4.44. Carrageenan-Induced Paw Edema

To induce paw edema, ICR mice were injected with 1% carrageenan (50 μL) on the plantar side of the right hind paw. Compound 3d (50 mg/kg), vehicle (sesame oil), and indomethacin (20 mg/kg) as a reference drug with proved anti-inflammatory effect were administered via gastric gavage 1 h before phlogogen injection. Mice were sacrificed 5 h after induction of paw edema. The percent of edema weight in carrageenan-injected compound-treated groups in comparison to that in vehicle-treated control group was calculated according to the formula:

where M₁ is the weight of the paw with carrageenan-induced edema; M₂ is the weight of the intact paws; compound and vehicle correspond to the compound- and vehicle-treated phlogogen-injected mice, respectively; and n is the number of mice in the control group (n = 9). Furthermore, paw material was collected for subsequent histological analysis.