Hyperpolarization-activated (Ih) current in mouse vestibular primary neurons.
The presence of a hyperpolarization-activated inward current (Ih) was investigated in mouse vestibular primary neurons using the whole-cell patch-clamp technique. In current-clamp configuration, injection of hyperpolarizing currents induced variations of membrane voltage with prominent time-dependent rectification increasing with current amplitudes. This effect was abolished by 2 mM Cs+ or 100 microM ZD7288. In voltage-clamp configuration, hyperpolarization pulses from -60 mV to -140 mV triggered a slow activating and non inactivating inward current that was sensitive to the two blockers, but insensitive to 5 mM Ba2+. Changing Na+ and K+ concentrations demonstrated that Ih current is carried by both these monovalent cations. This is the first demonstration of a Ih current in vestibular primary neurons.
Chabbert
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C
INSERM U432, UM2 cp 089, place E. Bataillon, 34095 Montpellier, Cedex 5, France.
Chambard
J M
JM
Valmier
J
J
Sans
A
A
Desmadryl
G
G
D000818:Animals; D002317:Cardiovascular Agents / Q000494:pharmacology; D002469:Cell Separation; D002586:Cesium / Q000494:pharmacology; D054815:Cyclic Nucleotide-Gated Cation Channels; D004558:Electric Stimulation; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D051379:Mice; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000378:metabolism; D015221:Potassium Channels; D011743:Pyrimidines / Q000494:pharmacology; D012964:Sodium / Q000378:metabolism; D014722:Vestibule, Labyrinth / Q000294:innervation*
D002317:Cardiovascular Agents; D054815:Cyclic Nucleotide-Gated Cation Channels; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D011743:Pyrimidines; C082246:ICI D2788; D002586:Cesium; D012964:Sodium; D011188:Potassium