Papers of the Week

Previous studies have shown that botulinum toxin type A (BoNT-A) attenuates nociception, but the underlying mechanisms remain unclear. Studies of experimental pain in humans have also shown conflicting results. Carrageenan is commonly used to produce short-term acute inflammation and hyperalgesia in animal models, and the effect of BoNT-A on carrageenan-induced pain in the masseter muscle has not been studied. This study evaluated the antinociceptive and anti-inflammatory effects of intramuscular injection of BoNT-A in an experimental model of inflammatory pain in the masseter muscle of rats.