Comparison of the early dynamics of systemic prostacyclin release after administration of tumor necrosis factor and endotoxin to healthy humans.

Excessive production of prostaglandins may be of importance for the development of organ damage in generalized infection. To investigate the role of tumor necrosis factor (TNF) in systemic prostacyclin release in gram-negative septicemia, the plasma concentrations of its stable metabolite 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were sequentially measured after intravenous bolus injections of recombinant human TNF (50 micrograms/m2; n = 6) and Escherichia coli endotoxin (2 ng/kg; n = 3) in healthy men. TNF induced a rapid increase in plasma 6-keto-PGF1 alpha from 0.11 +/- 0.01 to 0.44 +/- 0.15 ng/ml after 30 min (P less than .001). Endotoxin also elicited a rise in plasma 6-keto-PGF1 alpha, but peak values were reached only after 90 min (from 0.07 +/- 0.01 to 0.19 +/- 0.04 ng/ml; P less than .002). These results indicate that TNF may serve as an intermediate factor in systemic elaboration of prostacyclin in endotoxemia and gram-negative septicemia.