Endotoxin-induced changes in plasma concentrations of thromboxane and prostacyclin in neonatal calves given antiserum to a mutant Escherichia coli (J-5).

Plasma concentrations of the stable hydrolysis products of thromboxane (Tx) A2, TxB2, and prostacyclin (6-keto-prostaglandin F1 alpha; PGF1 alpha) were evaluated in 22 neonatal calves given endotoxin (0.5 microgram/kg) by slow IV infusion over a 5-hour period. The effect of pretreatment with bovine antiserum to a mutant of Escherichia coli O111:B4 (J-5) on plasma concentrations of these eicosanoids was determined. Plasma concentrations of TxB2 and 6-keto-PGF1 alpha were increased in response to endotoxin infusion. The mean plasma concentrations of TxB2 peaked 1 hour after endotoxin infusion began and was significantly increased from base line through 8 hours. Mean plasma 6-keto-PGF1 alpha concentration increased more slowly and was increased from base line only at 2 hours after endotoxin infusion began. Administration of bovine J-5 antiserum had no significant effect on endotoxin-induced thromboxane and prostacyclin production.