Erythrocyte lysate releases Ca2+from IP3-sensitive stores and activates Ca2+-dependent K+channels in rat basilar smooth muscle cells
| Autor: | Robert L Macdonald, He Zhang, Chul-Jin Kim, B. K. A. Weir |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Cell Extracts
Erythrocytes Patch-Clamp Techniques Potassium Channels Lysis Nicardipine Cerebral arteries Inositol 1 4 5-Trisphosphate Muscle Smooth Vascular Rats Sprague-Dawley Dogs Cerebral vasospasm medicine.artery Image Processing Computer-Assisted medicine Basilar artery Animals Channel blocker Egtazic Acid Chelating Agents Chemistry Vasospasm General Medicine Anatomy Calcium Channel Blockers medicine.disease Molecular biology Rats Neurology Vasoconstriction Basilar Artery Potassium Calcium Female Neurology (clinical) Intracellular medicine.drug |
| Zdroj: | Neurological Research. 20:23-30 |
| ISSN: | 1743-1328 0161-6412 |
| DOI: | 10.1080/01616412.1998.11740480 |
| Popis: | Erythrocyte lysate increases intracellular Ca2+ ([Ca2+]i), contracts cerebral arteries and has been suggested to be the causative agent for cerebral vasospasm. However, the mechanism of erythrocyte lysate-induced [Ca2+]i mobilization is not clear. This study was undertaken to investigate the action of erythrocyte lysate on [Ca2+]i mobilization by monitoring [Ca2+]i and the Ca(2+)-dependent K+ channels (KCa) in freshly isolated rat basilar artery smooth muscle cells. In a [Ca2+]i imaging study, erythrocyte lysate produced a biphasic response, a transient peak and a prolonged plateau [Ca2+]i elevation. In the absence of external Ca2+, erythrocyte lysate induced only a transient peak [Ca2+]i response without a marked plateau phase, indicating the [Ca2+]i was Ca2+ released from internal stores. Erythrocyte lysate-induced plateau [Ca2+]i response was resistant to nicardipine, a voltage-dependent Ca2+ channel blocker, but was abolished by EGTA. Elevation of [Ca2+]i induced by erythrocyte lysate contracted smooth muscle cells. In the electrophysiological study, elevation of [Ca2+]i by erythrocyte lysate increased KCa currents in whole-cell patch-clamp configuration. This effect of erythrocyte lysate on KCa was blocked by heparin, an antagonist of IP3 receptors. We conclude that erythrocyte lysate releases Ca2+ from IP3-sensitive intracellular stores and produces Ca2+ entry from voltage-independent Ca2+ pathways. |
| Databáze: | OpenAIRE |
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