Chemical Permeation Enhancers Enhance Nerve Blockade by Toxins

摘要: Chemical permeation enhancers (CPEs) improve access of local anesthetics to the nerve, thereby improving their performance. Surfactants, representing three CPE sub-groups: anionic, cationic, and nonionic surfactants, were co-injected with tetrodotoxin (TTX) or bupivacaine at sciatic nerve Sprague-Dawley rats. All produced marked concentration-dependent improvements in frequency duration block TTX but not bupivacaine. An vitro toxicity assay showed a wide range myotoxicity, vivo histological assessment no signs muscle damage concentrations CPEs that half-maximal increase TTX. There was systematic relationship between enhancers' charge hydrophobicity enhancement potency. Thus, can provide prolongation blockade from TTX, without apparent tissue toxicity, therefore enhance clinical applicability for prolonged-duration anesthesia.