Role of a striatal slowly inactivating potassium current in short-term facilitation of corticostriatal inputs: a computer simulation study.
Striatal output neurons (SONs) integrate glutamatergic synaptic inputs originating from the cerebral cortex. In vivo electrophysiological data have shown that a prior depolarization of SONs induced a short-term (</=1 sec) increase in their membrane excitability, which facilitated the ability of corticostriatal synaptic potentials to induce firing. Here we propose, using a computational model of SONs, that the use-dependent, short-term increase in the responsiveness of SONs mainly results from the slow kinetics of a voltage-dependent, slowly inactivating potassium A-current. This mechanism confers on SONs a form of intrinsic short-term memory that optimizes the synaptic input-output relationship as a function of their past activation.
Mahon
S
S
Institut des Neurosciences, Département de Neurochimie-Anatomie, Université Pierre et Marie Curie, F-75005 Paris, France. severine.mahon@snv.jussieu.fr
Deniau
J M
JM
Charpier
S
S
Delord
B
B
D000818:Animals; D003198:Computer Simulation; D003342:Corpus Striatum / Q000166:cytology / Q000502:physiology*; D004525:Efferent Pathways / Q000502:physiology; D004553:Electric Conductivity; D004558:Electric Stimulation; D007700:Kinetics; D008297:Male; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology; D015221:Potassium Channels / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000502:physiology
D015221:Potassium Channels