Effects of polymyxin B on selected features of equine carbohydrate overload.
Gram negative endotoxins play a contributory role in the syndrome which results from over consumption of carbohydrates by horses and ponies. Since the antibiotic polymyxin B exerts a direct anti-endotoxin effect by chemically modifying the active lipid A moiety of endotoxin, it might be expected to protect horses after carbohydrate overload and provide a new therapeutic and experimental tool for this condition. The present study was undertaken to evaluate the effect of polymyxin B on hemostatic, hemodynamic, acid-base, and clinical aspects of the syndrome resulting from carbohydrate overload. Experimentally-induced carbohydrate overload resulted in lactic acidosis, hypercoagulability, hypovolemic shock and lameness. Although there was a slight delay in the onset of clinical signs resulting from experimental carbohydrate overload in treated animals, polymyxin B administered iv at 2.5 mg/kg every 6 hr failed to significantly ameliorate the coagulopathy, acidosis, lameness and shock induced by alimentary carbohydrate overload.
Raisbeck
M F
MF
College of Veterinary Medicine, University of Missouri, Columbia 65201
Garner
H E
HE
Osweiler
G D
GD
D000137:Acid-Base Imbalance / Q000517:prevention & control; D000818:Animals; D001778:Blood Coagulation Disorders / Q000517:prevention & control; D002241:Carbohydrates / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D006439:Hemodynamics / Q000187:drug effects; D006736:Horses; D011112:Polymyxin B / Q000627:therapeutic use*; D011113:Polymyxins / Q000627:therapeutic use*
D002241:Carbohydrates; D011113:Polymyxins; D011112:Polymyxin B