RESUMO
Botulinum toxin-A ( botulinum toxin-A, BTX-A) is a double chain polypeptide structure formed by 100 kDa heavy chain and 50 kDa light chain through disulfide bond. The light chain is a kind of protease, which can combine with the fusion protein at the neuromuscular junction to prevent synaptic vesicles from anchoring on cell membrane and release acetylcholine, thus interfering with the transmission of nerve impulses. In recent years, the discussion on the clinical application of BTX-A has been a hot spot. Studies have shown that Botulinum toxin A (BTX-A) can effectively treat pain, exerting the characteristics of sustainable effect without addiction, but the mechanism of action of BTX-A is still controversial. This article reviews the mechanism of BTX-A in peripheral and central nervous system.