SUBCELLULAR-DISTRIBUTION OF CA2+ RELEASE CHANNELS UNDERLYING CA2+ WAVES AND OSCILLATIONS IN EXOCRINE PANCREAS
SUBCELLULAR-DISTRIBUTION OF CA2+ RELEASE CHANNELS UNDERLYING CA2+ WAVES AND OSCILLATIONS IN EXOCRINE PANCREAS
复制标题
DOI：
10.1016/0092-8674(93)90514-q
复制
发表时间：
1993-08-27
期刊：
影响因子：
64.5
通讯作者：
MIYASHITA, Y
中科院分区：
文献类型：
--
作者：
KASAI, H;LI, YX;MIYASHITA, Y
激动剂触发外分泌腺细胞中的 Ca2+ 波和振荡。我们的共聚焦 Ca2+ 成像揭示了大鼠胰腺腺泡细胞中 Ca2+ 波的三个不同阶段。 Ca2+ 浓度的上升始于颗粒区域中的一个小触发区或 T 区；然后，Ca2+波在该区域内快速传播，并且在高激动剂浓度下，缓慢向基极传播。从贴片移液管注射肌醇 1,4,5-三磷酸 (IP3) 或 Ca2+ 表明 T 区存在高灵敏度 IP3 受体，颗粒区存在 Ca2+ 诱导的 Ca2+ 释放通道，基底区存在低灵敏度 IP3 受体。 T 区的 IP3 受体似乎会产生自主的 Ca2+ 尖峰并启动模式化的 Ca2+ 振荡。因此，Ca2+ 释放通道的异质胞质定位在 Ca2+ 波和振荡中起着关键作用。
Agonists trigger Ca2+ waves and oscillations in exocrine gland cells. Our confocal Ca2+ imaging revealed three distinct phases during the Ca2+ waves in the rat pancreatic acinar cell. Rises in Ca2+ concentration were initiated at a small trigger zone, or T zone, in the granular area; then, Ca2+ waves rapidly spread within the area and, at high agonist concentrations, propagated slowly toward the basal pole. Injection of inositol 1,4,5-trisphosphate (IP3) or Ca2+ from patch pipettes demonstrated the presence of high sensitivity IP3 receptors at the T zone, Ca2+-induced Ca2+ release channels in the granular area, and low sensitivity IP3 receptors in the basal area. The IP3 receptors at the T zone appeared to generate autonomous Ca2+ spikes and to initiate patterned Ca2+ oscillations. Thus, heterogeneous cytosolic localization of Ca2+ release channels plays a key role in Ca2+ waves and oscillations.