Gene expression of nAChR, SNAP-25 and GAP-43 in skeletal muscles following botulinum toxin A injection: a study in rats

Conclusions: Specific nAChR subunit mRNA expression up-regulates and then returns to normal within two weeks, preceding changes in NMJ morphometry. Although GAP-43 participates in nerve sprouting, no increase of GAP-43 mRNA occurred following BoNT-A. Delayed up-regulation of SNAP-25 mRNA might be associated with muscle functional recovery.