Tuning photochromic ion channel blockers

ACS Chem Neurosci. 2011 Sep 21;2(9):536-43. doi: 10.1021/cn200037p. Epub 2011 Jun 9.


Photochromic channel blockers provide a conceptually simple and convenient way to modulate neuronal activity with light. We have recently described a family of azobenzenes that function as tonic blockers of K(v) channels but require UV-A light to unblock and need to be actively switched by toggling between two different wavelengths. We now introduce red-shifted compounds that fully operate in the visible region of the spectrum and quickly turn themselves off in the dark. Furthermore, we have developed a version that does not block effectively in the dark-adapted state, can be switched to a blocking state with blue light, and reverts to the inactive state automatically. Photochromic blockers of this type could be useful for the photopharmacological control of neuronal activity under mild conditions.

Keywords: azobenzenes; ion channel blockers; photochromic molecules; photopharmacology; voltage-gated potassium channels.

MeSH terms

  • Animals
  • Cerebellum / drug effects
  • Cerebellum / metabolism
  • Delayed Rectifier Potassium Channels / drug effects
  • Electrons
  • Electrophysiological Phenomena
  • HEK293 Cells
  • Humans
  • Microelectrodes
  • Patch-Clamp Techniques
  • Photochemistry
  • Potassium Channel Blockers / chemical synthesis*
  • Potassium Channel Blockers / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Solvents
  • Spectrophotometry, Ultraviolet
  • Stereoisomerism
  • Thermodynamics


  • Delayed Rectifier Potassium Channels
  • Potassium Channel Blockers
  • Solvents

Grants and funding

National Institutes of Health, United States