Induction of myelination in the central nervous system by electrical activity.
The oligodendrocyte is the myelin-forming cell in the central nervous system. Despite the close interaction between axons and oligodendrocytes, there is little evidence that neurons influence myelinogenesis. On the contrary, newly differentiated oligodendrocytes, which mature in culture in the total absence of neurons, synthesize the myelin-specific constituents of oligodendrocytes differentiated in vivo and even form myelin-like figures. Neuronal electrical activity may be required, however, for the appropriate formation of the myelin sheath. To investigate the role of electrical activity on myelin formation, we have used highly specific neurotoxins, which can either block (tetrodotoxin) or increase (alpha-scorpion toxin) the firing of neurons. We show that myelination can be inhibited by blocking the action potential of neighboring axons or enhanced by increasing their electrical activity, clearly linking neuronal electrical activity to myelinogenesis.
Demerens
C
C
Laboratoire de Neurobiologie Cellulaire, Moléculaire et Clinique, Institut National de la Santé et de la Recherche Médicale, Unité 134, Hôpital de la Salpêtrière, Université Pierre et Marie Curie, Paris, France.
Stankoff
B
B
Logak
M
M
Anglade
P
P
Allinquant
B
B
Couraud
F
F
Zalc
B
B
Lubetzki
C
C
D000200:Action Potentials; D000818:Animals; D002478:Cells, Cultured; D002490:Central Nervous System / Q000254:growth & development*; D004558:Electric Stimulation; D051379:Mice; D008854:Microscopy, Electron; D009186:Myelin Sheath / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D009900:Optic Nerve / Q000254:growth & development; D011188:Potassium / Q000494:pharmacology; D012604:Scorpion Venoms / Q000494:pharmacology; D015222:Sodium Channels / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors
D012604:Scorpion Venoms; D015222:Sodium Channels; D013779:Tetrodotoxin; D011188:Potassium