Saxitoxin binding to central and peripheral nervous tissue of the myelin deficiency (md) mutant rat.

Tritium-labeled saxitoxin binding was assayed in the CNS and PNS of normal and of 'myelin deficiency' (md) mutant rat pups. This mutant in the Wistar rat is characterized by a virtually complete amyelination of the CNS, the PNS being normal. No significant difference was found in the saxitoxin binding capacity of md and normal brain, spinal cord, or sciatic nerves. This suggests that the presence or absence of myelin does not influence the number of voltage-sensitive sodium channels in the rat.