Analysis of increased leukocyte ratio induced by tumor necrosis factor-alpha using several inhibitors in the undisturbed microcirculation of the rat mesentery.

Increased leukocyte ratio induced by intraperitoneal injection of TNF-alpha was analyzed in undisturbed rat mesentery venules, a long-term experimental model. TNF-alpha induced a biphasic increase in PMNL ratio in the mesentery venules; in particular, there was a large increase in PMNL ratio 3 h after injection of TNF-alpha. Anti-P and anti-L-selectin compounds, fucoidin and dextran sulfate, inhibited the PMNL ratio by about 40%. Dexamethasone completely inhibited the increased ratio. These results suggest that all selectins may be involved in the increased ratio, i.e. rolling and adhesion reaction.