Figure 1.

BoNT/A counteracts mechanical allodynia induced by chronic constriction injury (CCI) in mice. (A) Mechanical allodynia, expressed as withdrawal thresholds of applied force, of ipsi- and contralateral hindpaws as function of postoperative days in BoNT/A mice that received ipsi- and contralateral intraplantar injections of BoNT/A (15 pg/paw), either 5 (, ipsi; , contra) or 12 (, ipsi; , contra) days after CCI. Contralateral hindpaw was injected to check for possible neuroparalytic effect of peripheral BoNT/A injection. (B) Withdrawal thresholds of ipsi- and contralateral hindpaws as function of postoperative days after a intraplantar injections, into ipsi- and contralateral hindpaws, of BoNT/A 7.5 pg/paw (, ipsi; , contra) or BoNT/A 15 pg/paw (, ipsi; , contra) at day 5 after CCI (dashed). (C) Effect of a single intraplantar injection of BoNT/A (, 15 pg/paw) into the hindpaw contralateral to the injury. Corresponding ipsilateral hindpaws were injected with saline (). Injections performed at day 5 (dashed). (D) Withdrawal thresholds of ipsi- and contralateral hindpaws as function of postoperative days after a intraplantar injections, into ipsi- and contralateral hindpaws, of BoNT/B 3.75 pg/paw (, ipsi; , contra) at day 5 after CCI (dashed). For (A-D), control curves of ipsi- () and contralateral () withdrawal thresholds in saline-injected hindpaws at day 5 are reported for comparisons. Dashed lines represents the day of injection while day 0 indicates the day of injury. For further details, see [89,91].