Calcium oscillations in single cultured Chinese hamster ovary cells stably transfected with a cloned human cholecystokinin (CCK)B receptor.
Calcium oscillations in single cultured Chinese hamster ovary cells stably transfected with a cloned human cholecystokinin (CCK)B receptor.
复制标题
DOI：
10.1254/jjp.75.33
复制
发表时间：
1997-09
期刊：
影响因子：
--
通讯作者：
K. Akagi;T. Nagao;T. Urushidani
中科院分区：
文献类型：
--
作者：
K. Akagi;T. Nagao;T. Urushidani
在稳定表达克隆的人胆囊收缩素（CCK）B/胃泌素受体的中国仓鼠卵巢细胞中，八肽胆囊收缩素（CCK-8）诱发[Ca 2 +]i增加，通过数字化视频成像fura-2荧光比率监测。在10 pM左右的浓度下，CCK-8引起[Ca 2 +]i振荡，该振荡被磷脂酶C抑制剂U-73122、蛋白激酶C抑制剂H7以及磷脂酶A2（PLA 2）抑制剂ONO-RS-082和马兜铃酸消除细胞外Ca 2+所阻断。在较高浓度下，CCK-8诱导单一的双相[Ca 2 +]i上升，包括一个大的峰值，随后是一个较低的持续平台，而响应变成[Ca 2 +]i振荡时，细胞外Ca 2+被消除或包括PLA 2抑制剂。CCK-8刺激花生四烯酸的释放，这是由马兜铃酸抑制。花生四烯酸引起的[Ca ~（2+）]i的增加依赖于细胞外Ca ~（2+）。这些结果表明，PLA 2的激活可能参与，至少部分地，在钙内流，维持持续的平台期的[Ca 2 +]i以及[Ca 2 +]i振荡时，CCKB受体被刺激。
In Chinese hamster ovary cells stably expressing the cloned human cholecystokinin (CCK)B/ gastrin receptor, cholecystokinin octapeptide (CCK-8) evoked increases in [Ca2+]i monitored by digitized video imaging of fura-2 fluorescence ratios. At concentrations around 10 pM, CCK-8 elicited [Ca2+]i oscillations, which were blocked by elimination of extracellular Ca2+, by a phospholipase C inhibitor, U-73122, by a protein kinase C inhibitor, H7, as well as by phospholipase A2 (PLA2) inhibitors, ONO-RS-082 and aristolochic acid. At higher concentrations, CCK-8 induced a single biphasic [Ca2+]i rise consisting of a large peak followed by a lower sustained plateau, while the response turned into [Ca2+]i oscillation when the extracellular Ca2+ was eliminated or a PLA2 inhibitor was included. CCK-8 stimulated the release of arachidonic acid, and this was inhibited by aristolochic acid. Arachidonic acid caused an increase in [Ca2+]i which was dependent upon extracellular Ca2+. These results suggest that the activation of PLA2 might be involved, at least in part, in the Ca2+ influx that maintains the sustained plateau phase of [Ca2+]i as well as the [Ca2+]i oscillation when CCKB receptors are stimulated.