Summary
The objective of this study was to measure the synovial and plasma concentration of
carprofen in normal and osteoarthritic stifle joints throughout a 12-hour period.
Eight healthy male mixed breed hound dogs with chronic right stifle osteoarthritis
(OA) secondary to right cruciate ligament transection, were used. Each dog was treated
with carprofen (2mg/kg every 12 hours) for 14 days at four different time periods.
Prior to treatment, each dog had baseline data collected that included two force plate
evaluations (seven days apart), synovial fluid, and plasma collections. Plasma samples
were collected at three hours post drug administration on days two, four, six, eight,
10, and 12. On days #7 and 14 plasma, serum, bilateral stifle synovial fluid and ground
reaction forces (GRFs) were collected at three, six, nine, or 12 hours post-medication,
depending upon the test protocol. Vertical and cranio-caudal ground reaction forces
were recorded at each time period. Plasma concentrations measured at three hours remained
constant over each testing protocol. There were not any differences between the plasma
carprofen concentrations at three, nine, or 12 hours between days #7 or 14. A significant
difference was not found in the carprofen synovial concentrations between left and
right stifles at any time. Significant increases in vertical impulse data were found
at six hours post-treatment, for all of the collection periods on days three, seven
and 14. During the study, there was not any indication that carprofen had a ‘preference’
for the OA stifle as opposed to the normal stifle. Carprofen administration increased
the total force transmitted through the abnormal limb.
Carprofen concentrations in the plasma and synovial fluid and ground reaction forces
were measured in dogs with single stifle osteoarthritis at three, six, nine and 12
hours following dosing at 2 mg/kg every 12 hours. Carprofen did not have a ‘preference’
for the OA stifle as opposed to the normal stifle. Carprofen administration increased
the total force transmitted through the abnormal limb.
Keywords
Plasma - synovial fluid - carprofen - osteoarthritis
