Abstract
When a streptococcal preparation OK-432 was i. p. injected for the treatment of carcinomatous pleuritis and peritonitis, anti-tumor polymorphonuclear leukocytes (PMN) accumulated into the cavity. We proved that PMN accumulated from the peritoneum into the peritoneal cavity and chemotactic factors derived from the complement played a significant role on the accumulation in rats. Here, we examined the association of arachidonic acid metabolites with the PMN accumulation using in vivo system in rats. When various kinds of inhibitors of arachidonic acid cascade were reacted with OK-432 for 3 hrs through filter membranes placed on the turned peritoneum of rats, prednisolone and indomethacin reduced the accumulation of PMN onto filter membranes. OKY 046, AA 861, and azelastine also inhibited PMN accumulation in a dose-dependent manner, and these inhibitions were confirmed by histological examination. On the other hand, STA2 promoted PMN accumulation. These reagents did not inhibit C5a generation by OK-432 in vitro. It was concluded that chemotactic factors derived from arachidonic acid cascade such as TXA2, HETEs, and LTB2 were associated with PMN accumulation by OK-432.
