Effects of pentoxifylline on hemorheologic alterations induced by incremental treadmill exercise in thoroughbreds.
OBJECTIVE
To determine whether pentoxifylline treatment altered hematologic, rheologic, electrolyte, or blood gas test results of Thoroughbreds during submaximal treadmill exercise.


METHODS
5 healthy Thoroughbreds that had raced within the past year and had no history of exercise-induced pulmonary hemorrhage.


METHODS
Mixed venous blood samples were obtained before exercise, at treadmill speeds of 9 and 13 m/s, and 20 minutes after exercise; hematologic, rheologic, electrolyte, and blood gas test results were determined.


RESULTS
Pentoxifylline treatment resulted in a 45% reduction in RBC filtration pressures for horses at rest. The improved RBC filterability persisted during treadmill exercise. Horses treated with pentoxifylline had a greater decrease in Po2 values and a lesser increase in plasma lactate concentration during treadmill exercise.


CONCLUSIONS
Administration of pentoxifylline improved RBC deformability of horses at rest and during treadmill exercise.


CONCLUSIONS
Improved RBC deformability resulting from pentoxifylline treatment may reduce exercise-associated shear stress in pulmonary capillaries, thereby attenuating exercise-induced pulmonary hemorrhage.
Weiss
D J
DJ
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA.
Geor
R J
RJ
Burger
K
K
D000704:Analysis of Variance; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D001809:Blood Viscosity / Q000187:drug effects; D004573:Electrolytes / Q000097:blood*; D004907:Erythrocyte Deformability / Q000187:drug effects*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006736:Horses / Q000502:physiology*; D007773:Lactates / Q000097:blood; D008297:Male; D009919:Orchiectomy; D010100:Oxygen / Q000097:blood*; D010431:Pentoxifylline / Q000494:pharmacology*; D010805:Physical Conditioning, Animal; D005082:Physical Exertion; D012212:Rheology
D001798:Blood Proteins; D004573:Electrolytes; D007773:Lactates; D010100:Oxygen; D010431:Pentoxifylline