Effect of exercise on serum concentration of cartilage oligomeric matrix protein in Thoroughbreds.
OBJECTIVE
To evaluate changes in serum cartilage oligomeric matrix protein (COMP) concentrations in response to exercise in horses.


METHODS
15 horses in experiment 1 and 27 horses in experiment 2.


METHODS
In experiment 1, 15 Thoroughbreds free of orthopedic disease underwent a standardized exercise protocol. Running velocity and heart rate (HR) were recorded, and blood samples were collected immediately before (baseline) and 1, 5, and 24 hours after a single episode of exercise. In experiment 2, 27 horses underwent 9 stages of a training program in which each stage consisted of 4 to 8 consecutive daily workouts followed by a rest day. Blood samples were collected immediately before the first and final daily workouts in each stage. Serum COMP concentrations were measured via inhibition ELISA with a monoclonal antibody (14G4) against equine COMP.


RESULTS
In experiment 1, mean serum COMP concentration was significantly higher than baseline 1 and 5 hours after exercise and returned to baseline concentrations 24 hours after exercise. Mean serum baseline COMP concentration increased as the velocity of running at maximum HR and at an HR of 200 beats/min increased, being significantly higher during the third and fourth exercise tests than during the first. In experiment 2, mean baseline COMP concentration at the final workout of each stage was significantly higher than that at the first workout, beginning with stage 3.


CONCLUSIONS
Serum COMP concentrations changed significantly in response to exercise. Exercise may enhance movement of COMP into the circulation as well as change the basal turnover rate of COMP.
Helal
Ibrahim E
IE
Department of Veterinary Surgery, Kagoshima University, 21-24 Korimoto 1-chome, Kagoshima 890-0065, Japan.
Misumi
Kazuhiro
K
Tateno
Oki
O
Kodama
Takeshi
T
Ishimaru
Mutsuki
M
Yamamoto
Junya
J
Miyakoshi
Daiske
D
Fujiki
Makoto
M
D000818:Animals; D016326:Extracellular Matrix Proteins / Q000097:blood*; D005260:Female; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000097:blood*; D006734:Horse Diseases / Q000097:blood / Q000378:metabolism; D006736:Horses / Q000097:blood* / Q000502:physiology*; D007592:Joint Diseases / Q000097:blood / Q000378:metabolism; D008297:Male; D064235:Matrilin Proteins; D010805:Physical Conditioning, Animal / Q000502:physiology*
D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins