Antisense inhibition of Na+/Ca2+ exchange during anoxia/reoxygenation in ventricular myocytes.
نویسندگان
چکیده
This study investigated the role of the Na+/Ca2+ exchanger (NCX) in regulating cytosolic intracellular Ca2+ concentration ([Ca2+]i) during anoxia/reoxygenation in guinea pig ventricular myocytes. The hypothesis that the NCX is the predominant mechanism mediating [Ca2+]i overload in this model was tested through inhibition of NCX expression by an antisense oligonucleotide. Immunocytochemistry revealed that this antisense oligonucleotide, directed at the area around the start site of the guinea pig NCX1, specifically reduced NCX expression in cultured adult myocytes by 90 +/- 4%. Antisense treatment inhibited evoked NCX activity by 94 +/- 3% and decreased the rise in [Ca2+]i during anoxia/reoxygenation by 95 +/- 3%. These data suggest that NCX is the predominant mechanism mediating Ca2+ overload during anoxia/reoxygenation in guinea-pig ventricular myocytes.
منابع مشابه
ROS are required for rapid reactivation of Na+/Ca2+ exchanger in hypoxic reoxygenated guinea pig ventricular myocytes.
The cardiac Na(+)/Ca(2+) exchanger (NCX) contributes to cellular injury during hypoxia, as its altered function is largely responsible for a rise in cytosolic Ca(2+) concentration ([Ca(2+)](i)). In addition, the NCX in guinea pig ventricular myocytes undergoes profound inhibition during hypoxia and rapid reactivation during reoxygenation. The mechanisms underlying these changes in NCX activity ...
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عنوان ژورنال:
- American journal of physiology. Heart and circulatory physiology
دوره 281 5 شماره
صفحات -
تاریخ انتشار 2001