OBJECTIVE: To determine if duration and time of onset of treatment with diclofenac sodium influence force recovery after exercise-induced muscle damage in rats. DESIGN: Randomized placebo-controlled trial. SETTING: Animal laboratory. ANIMALS: A total of 217 female adult Wistar rats. INTERVENTION: Rats were submitted to a protocol consisting of 450 eccentric contractions of the ankle dorsiflexors. Treatment by gavage with diclofenac sodium (1 mg/kg, twice daily) was started at different times pre- and postprotocol or for various treatment durations. MAIN OUTCOME MEASURES: In vitro contractile properties. RESULTS: When treatment was initiated shortly postprotocol, force recovery was roughly proportional to treatment duration during the first 3 days but not at 7 and 28 days postprotocol. A 7-day treatment was no more effective than 1- or 2-day treatments when force was measured at 7 and 28 days; however, such prolonged treatment had no deleterious effect on muscle force at either time. A single-dose prophylactic treatment was as effective as a 2-day treatment initiated soon after the protocol when force was assessed 2 days postprotocol; on the other end, a treatment delayed for 3 days had no effect when force was measured at 7 days. CONCLUSIONS: Treatment with diclofenac sodium extending past the acute inflammatory phase was no more effective than short and timely treatment in this model of skeletal muscle damage.
OBJECTIVE: To determine if duration and time of onset of treatment with diclofenac sodium influence force recovery after exercise-induced muscle damage in rats. DESIGN: Randomized placebo-controlled trial. SETTING: Animal laboratory. ANIMALS: A total of 217 female adult Wistar rats. INTERVENTION: Rats were submitted to a protocol consisting of 450 eccentric contractions of the ankle dorsiflexors. Treatment by gavage with diclofenac sodium (1 mg/kg, twice daily) was started at different times pre- and postprotocol or for various treatment durations. MAIN OUTCOME MEASURES: In vitro contractile properties. RESULTS: When treatment was initiated shortly postprotocol, force recovery was roughly proportional to treatment duration during the first 3 days but not at 7 and 28 days postprotocol. A 7-day treatment was no more effective than 1- or 2-day treatments when force was measured at 7 and 28 days; however, such prolonged treatment had no deleterious effect on muscle force at either time. A single-dose prophylactic treatment was as effective as a 2-day treatment initiated soon after the protocol when force was assessed 2 days postprotocol; on the other end, a treatment delayed for 3 days had no effect when force was measured at 7 days. CONCLUSIONS: Treatment with diclofenac sodium extending past the acute inflammatory phase was no more effective than short and timely treatment in this model of skeletal muscle damage.
Authors: Luke Vella; James F Markworth; Gøran Paulsen; Truls Raastad; Jonathan M Peake; Rod J Snow; David Cameron-Smith; Aaron P Russell Journal: Front Physiol Date: 2016-03-29 Impact factor: 4.566