Antinociceptive effects of A1 and A2 type botulinum toxins on carrageenan-induced hyperalgesia in rat

► Effects of A1 and A2 type botulinum toxin on carrageenan-induced hyperalgesia. ► Both A1LL and A2NTX had antinociceptive effects in the carrageenan-induced pain. ► Effects of A2NTX were apparent a few hours earlier and more efficacious than A1LL. ► A2NTX also reduced the increase in c-fos immunoreactivity in L4-L5 spinal segments.