Spinal myelopathy induced by subarachnoid batrachotoxin: Ultrastructure and electrophysiology

Axonal transport in rats rendered paraplegic following a single subarachnoid injection of either batrachotoxin or 6‐aminonicotinamide into the spinal cord

“…This appears to be due to the degeneration of neurons occurring immediately after injection of the toxin into the cord (Garcia et al, 1978). The TCA-precipitable radioactivity would include lipid radioactivity, which in normal animals is approximately 15% of the total (Wood and Boegman, 1975).…”

“…1976;Garcia et al, 1978;Deshpande et al, 1978). Control animals received injections of vehicle alone.…”

“…BTX leads to a decrease in resting membrane potential (RMP) of 6 mV within 24 hr, while 6-AN reduces the RMP by 9 mV within 48 hr (Albuquerque, 1976;Garcia et al, 1978;Deshpande et al, 284 BOEGMAN AND ALBUQUERQUE 1978). Evidence has accumulated suggesting that the maintenance of the RMP is under trophic regulation by factors synthesized in the motor neuron and transported to the muscle by axoplasmic transport (Deshpande et al, 1976;Albuquerque et al, 1971b, Albuquerque et al, 1972Guth, 1968;Tiedt et al, 1977).…”

“…A single injection of BTX into the subarachnoid space of the rat lumbar spinal cord results in immediate flaccid paralysis of both flexor and extensor muscles of the hind limbs (Albuquerque, 1976;Garcia et al, 1978); animals, however, begin to recover after three to four days. Similarly, following injection of a single dose of the neurotoxic drug 6-aminonicotinamide into the lumbar subarachnoidal space, the hind limbs become paralyzed.…”

“…Batrachotoxin, one of the toxic compounds isolated from the skin of the South American frog Phyllobates aurotaenia, increases the resting sodium permeability of most excitable membranes and leads to membrane depolarization (Albuquerque et al, 1971a). A single injection of BTX into the subarachnoid space of the rat lumbar spinal cord results in immediate flaccid paralysis of both flexor and extensor muscles of the hind limbs (Albuquerque, 1976;Garcia et al, 1978); animals, however, begin to recover after three to four days. Similarly, following injection of a single dose of the neurotoxic drug 6-aminonicotinamide into the lumbar subarachnoidal space, the hind limbs become paralyzed.…”