Effects of pretreatment with ketoprofen and phenylbutazone on experimentally induced synovitis in horses.
OBJECTIVE
To compare the analgesic and anti-inflammatory effects of the nonsteroidal anti-inflammatory drugs (NSAID), ketoprofen (2.20 and 3.63 mg/kg of body weight) and phenylbutazone (4.40 mg/kg), in an acute equine synovitis model.


METHODS
4 groups of 6 horses received NSAID or saline solution in a randomized design.


METHODS
24 clinically normal mares and geldings.


METHODS
Left intercarpal joints were injected with sterile carrageenan to induce synovitis at the same time as IV administration of NSAID or saline solution. Clinical assessments were made and synovial fluid was withdrawn at 0, 1, 3, 6, 9, 12, 24, and 48 hours.


RESULTS
The eicosanoids, prostaglandin E2 (PGE2) and leukotriene B4, increased in synovial fluid after synovitis induction in all horses then returned to near baseline by 48 hours. All NSAID-treated horses had decreased PGE2, compared with saline-treated horses. This effect lasted longer in phenylbutazone-treated horses than in ketoprofen-treated horses. There were no treatment effects on leukotriene B4. In saline-treated animals, lameness, joint temperature, and synovial fluid volume, protein concentration, and nucleated cells increased 3 to 12 hours after induction, with marked reduction by 48 hours. Only phenylbutazone treatment reduced lameness, joint temperature, and synovial fluid volume.


CONCLUSIONS
Phenylbutazone was more effective than ketoprofen in reducing lameness, joint temperature, synovial fluid volume, and synovial fluid PGE2. Results do not support lipoxygenase inhibition by either NSAID.


CONCLUSIONS
This reversible model induced synovial fluid alterations similar to those observed in horses with septic arthritis. Results indicate that phenylbutazone may be more useful than ketoprofen in treating acute joint inflammation.
Owens
J G
JG
Department of Veterinary Physiology, Pharmacology, and Toxicology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA.
Kamerling
S G
SG
Stanton
S R
SR
Keowen
M L
ML
Prescott-Mathews
J S
JS
D000208:Acute Disease; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D015232:Dinoprostone / Q000032:analysis / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D006734:Horse Diseases / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D006736:Horses; D007596:Joints / Q000378:metabolism / Q000503:physiopathology; D007660:Ketoprofen / Q000627:therapeutic use*; D007794:Lameness, Animal / Q000209:etiology / Q000503:physiopathology; D007975:Leukotriene B4 / Q000032:analysis / Q000378:metabolism; D008297:Male; D010653:Phenylbutazone / Q000627:therapeutic use*; D011506:Proteins / Q000032:analysis; D013582:Synovial Fluid / Q000737:chemistry; D013585:Synovitis / Q000139:chemically induced / Q000188:drug therapy / Q000662:veterinary*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D011506:Proteins; D007975:Leukotriene B4; D007660:Ketoprofen; D010653:Phenylbutazone; D015232:Dinoprostone