The Effect Erythrocyte lysate on Intracellular Calcium Concentration and the Potassium Channel in Cerebral Vasular Smooth Muscle Cells.
- Author:
Chul Jin KIM
1
Author Information
1. Department of Neurosurgery, Chonbuk National University School of Medicine, Chonju, Korea.
- Publication Type:Original Article
- Keywords:
Erythrocyte lysate;
K+ channels;
IP3;
[Ca2+]i;
Vasospasm;
Cerebral smooth muscle cells
- MeSH:
Animals;
Basilar Artery;
Calcium*;
Cerebral Arteries;
Egtazic Acid;
Erythrocytes*;
Heparin;
Inositol 1,4,5-Trisphosphate Receptors;
Muscle, Smooth*;
Myocytes, Smooth Muscle*;
Nicardipine;
Potassium Channels*;
Potassium*;
Rats;
Vasospasm, Intracranial
- From:Journal of Korean Neurosurgical Society
1997;26(12):1644-1652
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Erythrocyte lysate increases intracellular Ca2+[Ca2+]i, causes contraction in cerebral arteries, and is thought to be the causative agent in cerebral vasospasm ; the mechanism of erythrocyte lysate-induced [Ca2+]i mobilization is not, however, clear. This study was undertaken to investigate the action of erythrocyte lysate on [Ca2+]i mobilization by monitoring [Ca2+]i and the Ca2+-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 prolonged plateau [Ca2+]i elevation ; in the absence of external Ca2+, it induced only a transient peak [Ca2+]i response without a marked plateau phase, indicating that peak [Ca2+]i was due to Ca2+ released from internal stores. The erythrocyte lysate-induced plateau [Ca2+]i response was resistant to nicardipine, a voltage-dependent Ca2+ channel blocker, but was abolished by EGTA. The elevation [Ca2+]i induced by erythrocyte lysate caused contraction in smooth muscle cells. During the electrophysiological study, elevation of [Ca2+]i by erythrocyte lysate increased Kca currents in whole-cell patch-clamp configuration ; this effect was blocked by heparin, an antagonist of IP3 receptors. We conclude that erythrocyte lysate releases Ca2+ from IP3-sensitive intracellular stores and induces Ca2+ entry from voltage-independent Ca2+ pathways.
