TREK-1 and TREK-2 Knockout Mice Are Not Resistant to Halothane or Isoflurane

Area of Science:

• Neuroscience
• Pharmacology
• Genetics

Background:

• TREK-1, a potassium leak channel, is a proposed molecular target for volatile anesthetics.
• TREK-1 knockout mice exhibit resistance to anesthetics, highlighting its potential role.
• Anesthetic hypersensitivity in Ndufs4 mutants was investigated in relation to TREK-1 function.

Purpose of the Study:

• To investigate the role of TREK-1 and TREK-2 channels in volatile anesthetic sensitivity.
• To determine if TREK channels mediate isoflurane-induced currents in spinal cord neurons.
• To explore alternative molecular targets for anesthetic action when TREK channels are absent.

Main Methods:

• Anesthetic sensitivities of wild-type, Trek-1, Trek-2, and Ndufs4 mutant mice were assessed.
• Patch-clamp electrophysiology was used to characterize isoflurane-sensitive currents in spinal cord neurons.
• Norfluoxetine was employed to identify TREK-dependent currents.

Main Results:

• TREK-1 or TREK-2 knockout, individually or combined, did not alter anesthetic sensitivity or righting reflex.
• Isoflurane-induced currents in wild-type cells were not affected by the absence of TREK-1 or TREK-2.
• However, isoflurane-induced currents in Trek mutants became insensitive to norfluoxetine.

Conclusions:

• TREK-1 and TREK-2 channels are not essential for volatile anesthetic sensitivity in mice.
• The study suggests that other, unidentified channels may mediate isoflurane-induced currents when TREK channels are deleted.
• These findings open avenues for exploring novel anesthetic targets.