Effect of PACs on exudate volume during carrageenin-induced pleurisy. At 4 h after intrapleural injection of carrageenin, the volume of the exudate was reduced by PACs (10, 30 and 60 mg/kg) administration. Each value is the mean ± s.e. mean of n = 6 experiments. °P < 0.01 versus saline. *P < 0.05 versus carrageenin. **P < 0.01 versus carrageenin.