Effect of polymyxin B on clinical signs, serum haptoglobin and glucose following experimental endotoxemia in sheep

In order to evaluate the effects of intravenous polymyxin B on clinical signs, serum haptoglobin and glucose concentrations’ following experimental endotoxemia in sheep the present study was performed. 20 clinically healthy Iranian fat-tailed sheep were randomly divided to 4 equal groups containing ploymyxin B 6000 and 12000 U/kg, positive and negative controls. Endotoxemia was induced by administration of lipopolysaccharide of Escherichia coli serotype O55:B5 at 0.5 µg/kg, intravenously. Blood sampling and clinical evaluation were performed prior and 1.5, 3, 4.5, 6, 24 and 48 hours after endotoxemia induction. Polymyxin B in both treatment groups was intravenously infused along with 2.5 liter of dextrose 5% plus to sodium chloride 0.45% at 20 mL/kgBW/hour. Positive control group received endotoxin and 2.5 liter intravenous fluids, subsequently, and fluid therapy was only performed in negative control one. Serum glucose and haptoglubin were assessed and haptoglubin in polymyxin B received groups was significantly lower than positive control one from hour 3 to 48 after endotoxemia induction (P