Evaluation of platelet activation and platelet-neutrophil aggregates in Thoroughbreds undergoing near-maximal treadmill exercise.
OBJECTIVE
To determine whether platelets become activated and form platelet-neutrophil aggregates during near-maximal treadmill exercise in horses.


METHODS
4 Thoroughbreds.


METHODS
Horses were subjected to 4 standardized exercise tests on a treadmill, and blood samples were collected before exercise, at treadmill speed of 12 m/s, and 5 minutes after exercise. Flow cytometric techniques were used to identify activated platelets, and flow cytometric and microscopic techniques were used to identify platelet-neutrophil aggregates.


RESULTS
Platelet-neutrophil aggregates increased from 2.8 +/- 0.4% at rest to 17.2 +/- 1.1% and 14.7 +/- 1.6% during and after exercise, respectively. Platelet activation was not detected during or after exercise.


CONCLUSIONS
Platelet-neutrophil aggregates consistently form during strenuous exercise in horses.
Weiss
D J
DJ
Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
Evanson
O A
OA
Fagliari
J J
JJ
Valberg
S
S
D000818:Animals; D001792:Blood Platelets / Q000502:physiology*; D002449:Cell Aggregation; D005080:Exercise Test / Q000662:veterinary; D005260:Female; D005434:Flow Cytometry; D006736:Horses / Q000097:blood*; D066298:In Vitro Techniques; D009504:Neutrophils / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D015539:Platelet Activation