Increasing extracellular calcium improves conduction in partially demyelinated rat fimbria in vitro.
1. We have tested the effect of changed concentrations of Ca2+ upon demyelination-induced conduction block in rat fimbria in vitro. 2. In a rat fimbria containing a region of acute focal demyelination induced by in vitro microinjection of lysophosphatidyl chloride (LPC) 6 days earlier, raising bath [Ca2+] to 4.4 mM improved conduction through the damaged area, while lowering it to 0.25 mM depressed conduction. 3. A contrary effect, consistent with the well-known effects of extracellular calcium ion on voltage-sensitive channels, was seen in non-lesioned preparations.
Newmark
J
J
Department of Neurology, School of Medicine, University of Louisville, KY 40292.
Reid
K H
KH
D000200:Action Potentials; D000818:Animals; D002118:Calcium / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D009431:Neural Conduction / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D002118:Calcium