A microcapsule technique for long-term conduction block of the sciatic nerve by tetrodotoxin

VN Martinov, A Njå - Journal of neuroscience methods, 2005 - Elsevier
VN Martinov, A Njå
Journal of neuroscience methods, 2005Elsevier
Tetrodotoxin (TTX) is a selective blocker of voltage-gated Na+ channels that is used to block
action potentials in vitro and in vivo. Maintaining a sufficiently high local concentration of
TTX in vivo to block conduction in a peripheral nerve is technically demanding and carries a
risk of systemic toxicity. We report that slow diffusion of TTX out of a microcapsule (glass
capillary) inserted beneath the epineurium of the sciatic nerve, with a loose cuff around the
nerve, combines high blocking efficacy with low systemic toxicity in rats and mice. The local …
Tetrodotoxin (TTX) is a selective blocker of voltage-gated Na+ channels that is used to block action potentials in vitro and in vivo. Maintaining a sufficiently high local concentration of TTX in vivo to block conduction in a peripheral nerve is technically demanding and carries a risk of systemic toxicity. We report that slow diffusion of TTX out of a microcapsule (glass capillary) inserted beneath the epineurium of the sciatic nerve, with a loose cuff around the nerve, combines high blocking efficacy with low systemic toxicity in rats and mice. The local anaesthesia and motor paralysis was stable for at least 4–6 weeks. The conduction block was reversible and did not cause any obvious nerve injury. Low cost and simple surgical implementation make this new system an interesting alternative to existing long-term drug delivery methods.
Elsevier