Long-lasting increases in intrinsic excitability triggered by inhibition.
Although experience-dependent changes in neural circuits are commonly assumed to be mediated by synaptic plasticity, modifications of intrinsic excitability may serve as a complementary mechanism. In whole-cell recordings from spontaneously firing vestibular nucleus neurons, brief periods of inhibitory synaptic stimulation or direct membrane hyperpolarization triggered long-lasting increases in spontaneous firing rates and firing responses to intracellular depolarization. These increases in excitability, termed firing rate potentiation, were induced by decreases in intracellular calcium and expressed as reductions in the sensitivity to the BK-type calcium-activated potassium channel blocker iberiotoxin. Firing rate potentiation is a novel form of cellular plasticity that could contribute to motor learning in the vestibulo-ocular reflex.
Nelson
Alexandra B
AB
Systems Neurobiology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
Krispel
Claudia M
CM
Sekirnjak
Chris
C
du Lac
Sascha
S
D000818:Animals; D000831:Animals, Newborn; D001030:Apamin / Q000494:pharmacology; D002104:Cadmium / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D017097:Electric Impedance; D004558:Electric Stimulation; D004594:Electrophysiology; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009498:Neurotoxins / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology; D013569:Synapses / Q000502:physiology; D013997:Time Factors; D014726:Vestibular Nuclei / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
D009498:Neurotoxins; D010455:Peptides; D002104:Cadmium; D001030:Apamin; D004533:Egtazic Acid; C064719:iberiotoxin; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium