Anti-minK antisense decreases the amplitude of the rapidly activating cardiac delayed rectifier K+ current.
Anti-minK antisense decreases the amplitude of the rapidly activating cardiac delayed rectifier K+ current.
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Anti-minK 反义降低了快速激活的心脏延迟整流 K 电流的幅度。
DOI：
10.1161/01.res.77.6.1246
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发表时间：
1995
影响因子：
20.1
通讯作者：
Roden,DM
中科院分区：
文献类型：
--
作者：
Yang,T;Kupershmidt,S;Roden,DM
在包括人类在内的几种物种的心肌细胞中，已经发现了具有不同生理特性的快速和缓慢激活延迟整流钾电流（分别为IKs和IKs）。虽然最小的K+通道蛋白（minK）的cDNA在某些系统中的结果在电流类似IKs的表达，该基因产物在通道功能的作用仍然存在争议。在心房肿瘤肌细胞（AT-1细胞）中，没有IKsis记录，但检测到minK mRNA，提高了minK基因表达提供尚未鉴定的功能的可能性。在这些实验中，AT-1细胞暴露于靶向从AT-1文库中克隆的minK cDNA的5′翻译起始位点的反义寡核苷酸。暴露后24至48小时测量细胞大小、IKr以及L型和T型Ca 2+电流，并与暴露于相应有义寡核苷酸或仅在培养基中生长的细胞中的数据进行比较。在50 nmol/L、250 nmol/L、1000 nmol/L和10 000 nmol/L的2个实验中，与正义和仅培养基对照细胞相比，反义寡核苷酸显著降低IKr（每个实验中每次处理n=3至6个细胞）。在1000 nmol/L时，反义暴露的细胞中的最大尾电流为2.5±0.1 pA/pF（平均值±SEM，n=28，6个单独的实验），有义暴露的细胞中的最大尾电流为6.6±0.4 pA/pF（n=27），仅培养基的细胞中的最大尾电流为5.4±0.6 pA/pF（n=21），暴露于随机寡核苷酸的细胞中的最大尾电流为5.8±0.7 pA/pF（n=9）。IKractivation，整流，失活，和敏感性的阻滞剂多非利特不受影响。两种不同的反义寡核苷酸产生相同的效果，并有没有影响的细胞大小或L-或T-型钙电流的反义治疗。这些数据表明，在AT-1细胞中，minK基因的表达在决定IKrampitude中起作用。
The rapidly and slowly activating delayed rectifier K+currents (IKrand IKs, respectively), which have different physiological properties, have been identified in cardiac cells from several species, including humans. Although expression of the minimal K+channel protein (minK) cDNA in some systems results in a current resembling IKs, the role of this gene product in channel function remains controversial. In atrial tumor myocytes (AT-1 cells), no IKsis recorded, but minK mRNA is detected, raising the possibility that expression of the minK gene serves an as-yet-unidentified function. In these experiments, AT-1 cells were exposed to antisense oligonucleotides targeting the 5′ translation start site of the minK cDNA cloned from an AT-1 library. Cell size, IKr, and L-type and T-type Ca2+currents were measured 24 to 48 hours after exposure and compared with data in cells exposed to the corresponding sense oligonucleotide or grown in medium only. Antisense oligonucleotide significantly reduced IKrcompared with sense and medium-only control cells in 0 of 2 experiments (n=3 to 6 cells per treatment in each experiment) at 50 nmol/L, 1 of 2 at 250 nmol/L, 6 of 6 at 1000 nmol/L, and 2 of 2 at 10 000 nmol/L. At 1000 nmol/L, maximum tail current in antisense-exposed cells was 2.5±0.1 pA/pF (mean±SEM, n=28, 6 separate experiments), 6.6±0.4 pA/pF in sense-exposed cells (n=27), 5.4±0.6 pA/pF in medium-only cells (n=21), and 5.8±0.7 pA/pF in cells exposed to a random oligonucleotide (n=9). IKractivation, rectification, deactivation, and sensitivity to the blocker dofetilide were unaffected. Two different antisense oligonucleotides produced the same effect, and there was no effect of antisense treatment on cell size or on L- or T-type Ca2+currents. These data indicate that in AT-1 cells, expression of the minK gene plays a role in determining IKramplitude.