Dihydropyridine Action on Voltage-dependent Potassium Channels Expressed in Xenopus Oocytes
| Autor: | Toshinori Hoshi, Vladimir Avdonin, E. F. Shibata |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Dihydropyridines
Patch-Clamp Techniques Potassium Channels Nifedipine Physiology Xenopus DHPS Article Membrane Potentials Mice parasitic diseases medicine Animals Patch clamp Ion channel Membrane potential biology Chemistry Dihydropyridine Hyperpolarization (biology) Calcium Channel Blockers biology.organism_classification Electric Stimulation Potassium channel Electrophysiology Biochemistry Oocytes Biophysics Ion Channel Gating medicine.drug |
| Zdroj: | The Journal of General Physiology |
| ISSN: | 1540-7748 0022-1295 |
| DOI: | 10.1085/jgp.109.2.169 |
| Popis: | Dihydropyridines (DHPs) are well known for their effects on L-type voltage-dependent Ca2+ channels. However, these drugs also affect other voltage-dependent ion channels, including Shaker K+ channels. We examined the effects of DHPs on the Shaker K+ channels expressed in Xenopus oocytes. Intracellular applications of DHPs quickly and reversibly induced apparent inactivation in the Shaker K+ mutant channels with disrupted N- and C-type inactivation. We found that DHPs interact with the open state of the channel as evidenced by the decreased mean open time. The DHPs effects are voltage-dependent, becoming more effective with hyperpolarization. A model which involves binding of two DHP molecules to the channel is consistent with the results obtained in our experiments. |
| Databáze: | OpenAIRE |
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