Dual action of endothelin-1 on the Ca2(+)-activated K+ channel in smooth muscle cells of porcine coronary artery
| Autor: | Helen S. Kim, Shiling Hu, Arco Y. Jeng |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
medicine.medical_specialty
BK channel Potassium Channels Swine Vasodilation In Vitro Techniques Muscle Smooth Vascular Membrane Potentials Internal medicine medicine Animals Channel blocker Pharmacology Oxadiazoles Isradipine Voltage-dependent calcium channel biology Chemistry Endothelins Calcium Channel Blockers Endothelin 1 Coronary Vessels Potassium channel Electrophysiology Endocrinology biology.protein Calcium Channels Rabbits medicine.symptom medicine.drug Muscle contraction Muscle Contraction |
| Zdroj: | European journal of pharmacology. 194(1) |
| ISSN: | 0014-2999 |
| Popis: | The effects of endothelin-1 (ET-1) on the activity of the large Ca2(+)-activated K+ channel (BK channel) in enzymatically dissociated smooth muscle cells of porcine coronary artery were studied with the cell-attached patch-clamp technique. ET-1 at concentrations between 0.1 and 10 nM potentiated the BK channel activity. This effect was maximal at 1 nM ET-1, resulting in an average of 4.2-fold increase in channel open-state probability as compared with control. ET-1 at concentrations higher than 10 nM produced an irreversible inhibition of the BK channel activity, primarily due to a marked decrease in the channel mean open-time. The activation by lower doses of ET-1, but not the inhibition by higher doses of ET-1, of the BK channel was blocked by 0.1 microM PN 200-110, a Ca2+ channel blocker. The modulation of the BK channel activity in smooth muscle cell membrane may be a possible mechanism for ET-induced vasodilator and vasoconstrictor actions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|