SODIUM PUMP ISOFORMS AND CARDIAC FUNCTION

描述(改编自申请人的摘要)：申请人提出 研究α3-Na，K-ATPase亚型在心脏中的作用 检验α3 Na，K-ATPase亚型是 适应于在压力条件下工作，因为它有较低的钠 亲和力高于α1和α2亚型。具体目标是：1) 研究强制过度表达Alpha3如何影响离子动态平衡和 基因操作和灌流的小鼠心肌细胞的收缩性能 心脏；2)测定预防Na，K-ATPase异构体的作用 30日龄心脏强迫过度表达Alpha3的转换 转基因小鼠；3)开发抑制新生儿α3泵的方法 并确定这种物质的功能后果。 压制。方法：将通过以下方式探讨结构-功能关系 研究转基因小鼠的心脏细胞和培养的大鼠心脏细胞 其中α3/α1异构体表达比率通过 反义技术。生命中的细胞内阳离子水平和离子通量 细胞将用荧光光谱学进行研究。那么它的影响 哇巴因对正常心脏和转基因心脏的收缩性能进行比较 使用视频显微镜和隔离心脏灌流。

DESCRIPTION (adapted from the applicant's abstract): The applicant proposes to study the role of the alpha3 Na,K-ATPase isoform in the heart focusing on testing the overall hypothesis that the alpha3 Na,K-ATPase isoform is adapted to function under conditions of stress since it has a lower Na affinity than alpha1 and alpha2 isoforms. The specific objectives are: 1) To examine how forced overexpression of alpha3 affects ionic homeostasis and contractility in genetically manipulated mouse heart cells and perfused hearts; 2) To determine the effect of preventing the Na,K-ATPase isoform switch by forcing overexpression of alpha3 in hearts of 30-day-old transgenic mice; 3) To develop methods to suppress alpha3 pumps in neonatal rat heart cells and determine the functional consequences of such suppression. Methods: Structure-function relationships will be probed by studying both heart cells from transgenic mice, and cultured rat heart cells in which the alpha3/alpha1 isoform expression ratio has been manipulated via antisense technology. Intracellular cation levels and fluxes in living cells will be studied with fluorescence spectroscopy. Then the effects of ouabain on contractility in normal and transgenic hearts will be compared using videomicroscopy and isolated heart perfusion.