Hippocampal A-type current and Kv4.2 channel modulation by the sulfonylurea compound NS5806
| Autor: | Paul Fischer, Robert Bähring, Katrin Witzel |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Patch-Clamp Techniques
Kinetics Analytical chemistry Tetrazoles Hippocampus In Vitro Techniques Hippocampal formation law.invention Cellular and Molecular Neuroscience law Potassium Channel Blockers Animals Humans Patch clamp Rats Wistar Dipeptidyl-Peptidases and Tripeptidyl-Peptidases Cells Cultured Neurons Pharmacology Chemistry Phenylurea Compounds HEK 293 cells Kv Channel-Interacting Proteins Long-term potentiation Potassium channel Rats HEK293 Cells Shal Potassium Channels Data Interpretation Statistical Biophysics Recombinant DNA |
| Zdroj: | Neuropharmacology. 63:1389-1403 |
| ISSN: | 0028-3908 |
| Popis: | We examined the effects of the sulfonylurea compound NS5806 on neuronal A-type channel function. Using whole-cell patch-clamp we studied the effects of NS5806 on the somatodendritic A-type current (ISA) in cultured hippocampal neurons and the currents mediated by Kv4.2 channels coexpressed with different auxiliary β-subunits, including both Kv channel interacting proteins (KChIPs) and dipeptidyl aminopeptidase-related proteins (DPPs), in HEK 293 cells. The amplitude of the ISA component in hippocampal neurons was reduced in the presence of 20 μM NS5806. ISA decay kinetics were slowed and the recovery kinetics accelerated, but the voltage dependence of steady-state inactivation was shifted to more negative potentials by NS5806. The peak amplitudes of currents mediated by ternary Kv4.2 channel complexes, associated with DPP6-S (short splice-variant) and either KChIP2, KChIP3 or KChIP4, were potentiated and their macroscopic inactivation slowed by NS5806, whereas the currents mediated by binary Kv4.2 channels, associated only with DPP6-S, were suppressed, and the NS5806-mediated slowing of macroscopic inactivation was less pronounced. Neither potentiation nor suppression and no effect on current decay kinetics in the presence of NS5806 were observed for Kv4.2 channels associated with KChIP3 and the N-type inactivation-conferring DPP6a splice-variant. For all recombinant channel complexes, NS5806 slowed the recovery from inactivation and shifted the voltage dependence of steady-state inactivation to more negative potentials. Our results demonstrate the activity of NS5806 on native ISA and possible molecular correlates in the form of recombinant Kv4.2 channels complexed with different KChIPs and DPPs, and they shed some light on the mechanism of NS5806 action. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect