Imaging of intracellular calcium stores in single permeabilized lens cells.
Imaging of intracellular calcium stores in single permeabilized lens cells.
复制标题
单个透化晶状体细胞中细胞内钙储存的成像。
DOI：
10.1152/ajpcell.1999.276.2.c426
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Louis,CF
中科院分区：
文献类型：
--
作者：
Churchill,GC;Louis,CF
利用mag-fura 2对渗透化绵羊晶状体细胞内的Ca2+储存进行成像，以表征其分布和对Ca2+释放剂的敏感性。肌醇1,4,5-三磷酸（IP3）或环adp核糖（cADPR）从由atp依赖性Ca2+泵维持的细胞内Ca2+储存中释放Ca2+。IP3拮抗剂肝素抑制IP3-但不抑制cADPR介导的Ca2+释放，而cADPR拮抗剂8-氨基-cADPR抑制cADPR-但不抑制IP3介导的Ca2+释放，表明IP3和cADPR通过不同的机制起作用。对IP3， cADPR和thapsigargin敏感的Ca2+储存似乎分布在所有细胞内区域。在一些细胞中，在核旁区域存在对IP3、cADPR、thapsigarin和2,4-二硝基酚不敏感的Ca2+储存，但不存在离子霉素。我们得出结论，晶状体细胞含有对IP3、cADPR和thapsigarin敏感的细胞内Ca2+储存，以及对所有这些药物不敏感的Ca2+储存。
Intracellular Ca2+stores in permeabilized sheep lens cells were imaged with mag-fura 2 to characterize their distribution and sensitivity to Ca2+-releasing agents. Inositol 1,4,5-trisphosphate (IP3) or cyclic ADP-ribose (cADPR) released Ca2+from intracellular Ca2+stores that were maintained by an ATP-dependent Ca2+pump. The IP3antagonist heparin inhibited IP3- but not cADPR-mediated Ca2+release, whereas the cADPR antagonist 8-amino-cADPR inhibited cADPR- but not IP3-mediated Ca2+release, indicating that IP3and cADPR were operating through separate mechanisms. A Ca2+store sensitive to IP3, cADPR, and thapsigargin appeared to be distributed throughout all intracellular regions. In some cells a Ca2+store insensitive to IP3, cADPR, thapsigargin, and 2,4-dinitrophenol, but not ionomycin, was present in a juxtanuclear region. We conclude that lens cells contain intracellular Ca2+stores that are sensitive to IP3, cADPR, and thapsigargin, as well as a Ca2+store that appears insensitive to all these agents.