[Protective effect of 764-3 on experimental inflammation]

The antiinflammatory effect of 764-3 was investigated in rat models of lung inflammation and pleurisy induced by bleomycin intratracheal instillation and carrageenan intrapleural cavity injection respectively. 4 mg/100 g BW.d 764-3 hypodermal injection significantly inhibited the lung inflammatory changes in bleomycin treated rats. Compared with the experimental group, lung index, histamine content in lung tissue and in bronchoalveolar lavage fluid (BALF), number of PMN in BALF and BALF beta-glucuronidase activity significantly deceased in the therapeutic rats. 8 mg/100 g BW 764-3 intramuscular injection significantly inhibited the volume, number of PMN, protein content and beta-glucuronidase activity increase in carrageenan-induced pleural exudate fluid. The antiinflammatory effect of 8 mg/100 g BW 764-3 was equal to that of 3 mg/100 g BW hydrocortisone. 4 mg/100 g BW 764-3 injection significantly inhibited the increases in PMN numbers and beta-glucuronidase activity in pleural exudate fluid. 2 mg/100 g BW 764-3 injection significantly inhibited the PMN increase in pleural exudate fluid only. 1 mg/100 g BW 764-3 injection showed no antiinflammatory effect. When 764-3 was administered orally, the antiinflammatory effect was unsatisfactory. 5 mg/100 mg BW 764-3 significantly inhibited the volume, number of PMN, protein content and beta-glucuronidase activity of carrageenan-induced pleural exudate fluid. 2.5 mg/100 g BW 764-3 significantly inhibited the volume and protein content increases in pleural exudate fluid. But 3.5 mg/100 g BW 764-3 showed no antiinflammatory effect. The authors indicate that the antiinflammatory effect of orally administered 764-3 was not stable.