Multiphoton stimulation of neurons.
We pulsed the activation of neurons using a femtosecond laser. Pyramidal neurons are depolarized and fire action potentials when high intensity mode-locked infrared light irradiates somatic membranes and axon initial segments. This depolarization is reversible, does not occur with CW laser light, and appears to be due to multiphoton excitation. We describe two regimes of multiphoton optical stimulation. Low intensity, long duration laser irradiation produces a sustained depolarization, insensitive to sodium channel blockers yet sensitive to antioxidants. On the other hand, high intensity, short duration irradiation can induce fast depolarizations, which appear due to different mechanism. The combination of multiphoton stimulation and optical probing could enable systematic analysis of circuits.
Hirase
Hajime
H
Department of Biological Sciences, Columbia University, New York, New York 10027, USA. hirase@axon.rutgers.edu
Nikolenko
Volodymyr
V
Goldberg
Jesse H
JH
Yuste
Rafael
R
D000200:Action Potentials / Q000187:drug effects / Q000528:radiation effects*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002839:Chromans / Q000494:pharmacology; D004396:Coloring Agents; D007259:Infrared Rays; D007834:Lasers; D051379:Mice; D008810:Mice, Inbred C57BL; D018408:Patch-Clamp Techniques; D017785:Photons; D017966:Pyramidal Cells / Q000502:physiology* / Q000528:radiation effects*; D026941:Sodium Channel Blockers; D013779:Tetrodotoxin / Q000494:pharmacology
D000975:Antioxidants; D002839:Chromans; D004396:Coloring Agents; D026941:Sodium Channel Blockers; D013779:Tetrodotoxin; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid