Contributions of low-threshold calcium current and anomalous rectifier (Ih) to slow depolarizations underlying burst firing in human neocortical neurons in vitro.
The slow depolarization that underlies the voltage-dependent burst-firing behavior of human neocortical neurons is mediated by a low-threshold calcium conductance in concert with the anomalous rectifier current, Ih. The slow depolarization could be elicited by depolarization from negative membrane potentials or as a rebound following hyperpolarization. The rebound depolarization was time- and voltage-dependent. Most of the slow depolarization was blocked by inorganic calcium blockers. The remainder of the depolarization and the 'sag' in the hyperpolarizing voltage responses were blocked by extracellular Cs+.
Foehring
R C
RC
Department of Anatomy and Neurobiology, University of Tennessee, Memphis 38163.
Waters
R S
RS
D000200:Action Potentials / Q000187:drug effects; D002118:Calcium / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002412:Cations / Q000494:pharmacology; D002540:Cerebral Cortex / Q000166:cytology*; D004828:Epilepsies, Partial / Q000473:pathology; D005260:Female; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000502:physiology; D012964:Sodium / Q000502:physiology; D013779:Tetrodotoxin / Q000494:pharmacology
D002121:Calcium Channel Blockers; D002412:Cations; D013779:Tetrodotoxin; D012964:Sodium; D011188:Potassium; D002118:Calcium