Treatment with root extracts reduces leukocyte recruitment into the pouch wall and their accumulation in the pouch exudate. The experimental groups in these and subsequent experiments were as follows: (1) Ctrl (gavage feeding with water and intrapouch injection of PBS); (2) MSU (gavage feeding with water and intrapouch injection of MSU crystals in PBS); and (3) MSU + extracts (gavage feeding with extracts and intrapouch injection of MSU crystals in PBS). (a) Leukocyte count in the pouch exudate, expressed as leukocytes per pouch. The numerical values (all × 106 ± standard error of the mean) were as follows: Ctrl, 0.26 ± 0.03; MSU, 7.80 ± 0.33; and MSU + extracts, 1.24 ± 0.18. The percentage changes detected in this and all other experiments are summarized in Table 3. (b) Polymorphonuclear cell density in the pouch wall (cells per × 600 field ± SEM): Ctrl, 5.30 ± 0.78; MSU, 31.02 ± 1.55; MSU + extracts, 10.08 ± 1.12. (c–e) H&E stains of representative sections from pouch walls obtained from control (c), MSU (d) and extract treatment (e) groups. Higher magnification revealed that the control wall contained mostly fibroblasts and mononuclear cells. Abundant polymorphonuclear cells were seen in the MSU-stimulated pouch wall (d), the number of which was decreased by treatment with the root extracts (e). Ctrl, control; H&E, hematoxylin and eosin; Hpf, high-power field (× 600); MSU, monosodium urate; PBS, phosphate-buffered saline; WBC, white blood cell count.