Advertisement

Assessment of leukotriene B4 production in leukocytes from horses with recurrent airway obstruction

Åsa LindbergDepartment of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, S-171 77 Stockholm, Sweden.
Department of Large Animal Clinical Sciences, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala, Sweden

Search for other papers by Åsa Lindberg in
Current site
Google Scholar
PubMed
Close
 DVM
,
N. Edward RobinsonPulmonary Laboratory, Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824-1314.

Search for other papers by N. Edward Robinson in
Current site
Google Scholar
PubMed
Close
 BVetMed, PhD
,
Barbro Näsman-GlaserDepartment of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, S-171 77 Stockholm, Sweden

Search for other papers by Barbro Näsman-Glaser in
Current site
Google Scholar
PubMed
Close
 BS
,
Marianne Jensen-WaernDepartment of Large Animal Clinical Sciences, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala, Sweden.

Search for other papers by Marianne Jensen-Waern in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
, and
Jan Åke LindgrenDepartment of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, S-171 77 Stockholm, Sweden.

Search for other papers by Jan Åke Lindgren in
Current site
Google Scholar
PubMed
Close
 MD, PhD

Abstract

Objective—To determine the ex vivo leukotriene (LT) biosynthesis in peripheral blood neutrophils (PBNs) and inflammatory cells in bronchoalveolar lavage fluid (BALF) obtained from horses affected with recurrent airway obstruction (RAO).

Animals—6 RAO-affected and 6 control horses.

Procedure—Before and 6, 24, and 48 hours after stabling, disease severity was determined subjectively by clinical and mucus scores and measurement of the maximal change in pleural pressure (ΔPplmax); PBNs were isolated and BALF samples were examined cytologically. The PBN and BALF cells were activated with a calcium ionophore in the presence of arachidonic acid, and production of LTC4 and LTB4 was measured per 106 cells.

Results—Clinical and mucus scores and ΔPplmax increased during stabling in RAO-affected horses, but not in control horses. In neutrophils and BALF cells from both groups, production of LTB4 exceeded that of LTC4. At all times, LTB4 production by PBNs was less in RAO-affected horses than it was in control horses. Before stabling, LTB4 production by cells in BALF was low in RAO-affected horses, but increased considerably after 6 hours of stabling. This increase coincided with the migration of neutrophils into the airways. In control horses, production of LTB4 did not change during stabling.

Conclusions and Clinical Relevance—Results suggested increased production of LTB4 in airways of RAO-affected horses, compared with control horses, that may contribute to the infiltration of neutrophils into the lungs and the sustained inflammation associated with RAO. ( Am J Vet Res 2004;65:289–295)

Abstract

Objective—To determine the ex vivo leukotriene (LT) biosynthesis in peripheral blood neutrophils (PBNs) and inflammatory cells in bronchoalveolar lavage fluid (BALF) obtained from horses affected with recurrent airway obstruction (RAO).

Animals—6 RAO-affected and 6 control horses.

Procedure—Before and 6, 24, and 48 hours after stabling, disease severity was determined subjectively by clinical and mucus scores and measurement of the maximal change in pleural pressure (ΔPplmax); PBNs were isolated and BALF samples were examined cytologically. The PBN and BALF cells were activated with a calcium ionophore in the presence of arachidonic acid, and production of LTC4 and LTB4 was measured per 106 cells.

Results—Clinical and mucus scores and ΔPplmax increased during stabling in RAO-affected horses, but not in control horses. In neutrophils and BALF cells from both groups, production of LTB4 exceeded that of LTC4. At all times, LTB4 production by PBNs was less in RAO-affected horses than it was in control horses. Before stabling, LTB4 production by cells in BALF was low in RAO-affected horses, but increased considerably after 6 hours of stabling. This increase coincided with the migration of neutrophils into the airways. In control horses, production of LTB4 did not change during stabling.

Conclusions and Clinical Relevance—Results suggested increased production of LTB4 in airways of RAO-affected horses, compared with control horses, that may contribute to the infiltration of neutrophils into the lungs and the sustained inflammation associated with RAO. ( Am J Vet Res 2004;65:289–295)