Effect of intensive exercise on plasmatic neutrophil elastase level in eventing and endurance horses.
BACKGROUND
Intensive exercise induces a systemic inflammatory response characterised by an increase of blood neutrophil count and myeloperoxidase (MPO) release. Neutrophil elastase (NE) could also contribute to tissues lesions by its proteinase activities.


OBJECTIVE
To compare plasmatic NE concentrations before and after different forms of intensive exercise.


METHODS
EDTA blood samples were taken from 51 eventing horses (EvH) and 32 endurance horses (EndH) were sampled before the race (T0). Blood sampling was performed 2 h (T1) after completing either phase D of a one or 2 star eventing competition (n = 51), or a 120 or 160 km endurance race (n = 32). Plasmatic NE and MPO were measured by a specific equine ELISA. Neutrophil counts and creatine kinase (CK) levels were also measured. A Wilcox on test for paired samples was used to compare mean values of neutrophils, CK, MPO and NE at T0 and T1 in EvH and in EndH. Correlations were calculated between all the 4 parameters in EvH and EndH.


RESULTS
At T0, mean NE levels were 14.43 ± 3.63 ng/ml for EvH and 11.7 ± 2.11 ng/ml for EndH. The competition induced a significant increase of NE levels in (58.57 ± 24.06 ng/ml) EvH and (95.74 ± 22.70 ng/ml) EndH (P < 0.05). NE was significantly (P < 0.0001) correlated to MPO in EvH (r = 0.293) and EndH (r = 0.594) and to CK (r = 0.297) in EndH (P < 0.0001). Neutrophils, CK and MPO were significantly increased between T0 and T1 in both types of horses.


CONCLUSIONS
Significant increase of NE (EndH) was observed after intense exercise with a significant correlation between NE and MPO. The huge variability in MPO and NE indicates that not all horses show the same intensity of systemic inflammatory response.
Equine European Centre of Mont-le-Soie, University of Liege, Mont-le-Soie, Vielsalm, Belgium. a.barnes@murdoch.edu.au
J P
JP
Lejeune
C
C
Sandersen
D
D
Votion
I
I
Caudron
L
L
Vander Heyden
T
T
Franck
J
J
Ceusters
A
A
Mouithys-Mickalad
A
A
Niesten
G
G
De La Rebière de Pouyade
D
D
Serteyn
D000818:Animals; D006736:Horses / Q000502:physiology*; D019272:Leukocyte Elastase / Q000097:blood* / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010805:Physical Conditioning, Animal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D013177:Sports
D009195:Peroxidase; D019272:Leukocyte Elastase