Thalamic microinfusion of antibody to a voltage-gated potassium channel restores consciousness during anesthesia

Anesthesiology. 2009 Apr;110(4):766-73. doi: 10.1097/aln.0b013e31819c461c.


Background: The Drosophila Shaker mutant fruit-fly, with its malfunctioning voltage-gated potassium channel, exhibits anesthetic requirements that are more than twice normal. Shaker mutants with an abnormal Kv1.2 channel also demonstrate significantly reduced sleep. Given the important role the thalamus plays in both sleep and arousal, the authors investigated whether localized central medial thalamic (CMT) microinfusion of an antibody designed to block the pore of the Kv1.2 channel might awaken anesthetized rats.

Methods: Male Sprague-Dawley rats were implanted with a cannula aimed at the CMT or lateral thalamus. One week later, unconsciousness was induced with either desflurane (3.6 +/- 0.2%; n = 55) or sevoflurane (1.2 +/- 0.1%; n = 51). Arousal effects of a single 0.5-microl infusion of Kv1.2 potassium channel blocking antibody (0.1- 0.2 mg/ml) or a control infusion of Arc-protein antibody (0.2 mg/ml) were then determined.

Results: The Kv1.2 antibody, but not the control antibody, temporarily restored consciousness in 17% of all animals and in 75% of those animals where infusions occurred within the CMT (P < 0.01 for each anesthetic). Lateral thalamic infusions showed no effects. Consciousness returned on average (+/- SD) 170 +/- 99 s after infusion and lasted a median time of 398 s (interquartile range: 279-510 s). Temporary seizures, without apparent consciousness, predominated in 33% of all animals.

Conclusions: These findings support the idea that the CMT plays a role in modulating levels of arousal during anesthesia and further suggest that voltage-gated potassium channels in the CMT may contribute to regulating arousal or may even be relevant targets of anesthetic action.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anesthesia, Inhalation*
  • Anesthetics, Inhalation / administration & dosage
  • Animals
  • Antibodies / metabolism
  • Arousal / physiology*
  • Consciousness* / drug effects
  • Consciousness* / physiology
  • Cytoskeletal Proteins
  • Desflurane
  • Drosophila
  • Isoflurane / administration & dosage
  • Isoflurane / analogs & derivatives
  • Kv1.2 Potassium Channel / metabolism*
  • Male
  • Methyl Ethers / administration & dosage
  • Microinjections / methods
  • Nerve Tissue Proteins
  • Potassium Channels / drug effects*
  • Potassium Channels / immunology
  • Potassium Channels / physiology
  • Rats
  • Rats, Sprague-Dawley
  • Sevoflurane
  • Thalamic Nuclei / anatomy & histology
  • Thalamic Nuclei / drug effects*
  • Thalamic Nuclei / metabolism


  • Anesthetics, Inhalation
  • Antibodies
  • Cytoskeletal Proteins
  • Kv1.2 Potassium Channel
  • Methyl Ethers
  • Nerve Tissue Proteins
  • Potassium Channels
  • activity regulated cytoskeletal-associated protein
  • Sevoflurane
  • Desflurane
  • Isoflurane