CYTOPLASMIC CA-2+ OSCILLATIONS EVOKED BY RECEPTOR STIMULATION, G-PROTEIN ACTIVATION, INTERNAL APPLICATION OF INOSITOL TRISPHOSPHATE OR CA-2+ SIMULTANEOUS MICROFLUORIMETRY AND CA-2+ DEPENDENT CL- CURRENT RECORDING IN SINGLE PANCREATIC ACINAR-CELLS
CYTOPLASMIC CA-2+ OSCILLATIONS EVOKED BY RECEPTOR STIMULATION, G-PROTEIN ACTIVATION, INTERNAL APPLICATION OF INOSITOL TRISPHOSPHATE OR CA-2+ SIMULTANEOUS MICROFLUORIMETRY AND CA-2+ DEPENDENT CL- CURRENT RECORDING IN SINGLE PANCREATIC ACINAR-CELLS
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DOI：
10.1002/j.1460-2075.1990.tb08162.x
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发表时间：
1990-03-01
期刊：
影响因子：
11.4
通讯作者：
PETERSEN, OH
中科院分区：
文献类型：
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作者：
OSIPCHUK, YV;WAKUI, M;PETERSEN, OH
用同时微量荧光法(Fura-2)和膜片钳全细胞记录技术，观察乙酰胆碱(ACh)、胆囊素(CCK)、三磷酸肌醇(Ins(1，4，5)P3)、三磷酸肌醇(Ins(1，4，5)P3)或钙离子对小鼠胰腺腺泡细胞胞浆游离钙浓度([Ca~(2+)]i)的影响。ACh(0.1-0.2µm)引起细胞整体[Ca~(2+)]_i的振荡性升高(显微荧光法)，这与细胞膜附近报告[Ca~(2+)]_i的钙依赖的氯电流的振荡是同步的。在相同的细胞中，较低的ACh浓度(0.05µm)引起较短的重复的氯电流脉冲，而在显微荧光记录中不伴随类似的尖峰。当细胞对09.1µm ACh无反应时，在持续ACh刺激的基础上添加咖啡因(1 MM)，导致在两种类型的记录中同步出现[Ca~(2+)]i振荡。CCK(10 NM)也可引起[Ca~(2+)]_i振荡，但两个稍宽的Ca~(2+)脉冲之间的间隔要长得多。内灌流100µmGTP-γ-S可引起类似的[Ca~(2+)]_i振荡。Ins(1，4，5)P3(10微米)可引起只在氯电流示踪中出现的短暂的[Ca~(2+)]_i峰，但在一个小细胞中，这些峰也在显微荧光记录中同步出现。咖啡因(1 MM)使这些钙脉冲变宽。通过向吸管中注入低或高的钙溶液，绕过正常的信号传递过程，[Ca~(2+)]i也被直接改变。在微量荧光记录中看到的相对平稳的[Ca~(2+)]i上升和下降伴随着类似的Cl-电流的上升和下降。在峰值之前和随后的下降阶段，出现了重复的、持续时间较短的氯离子电流尖峰。我们的结论是，受体刺激通过INS(1，4，5)P3诱发的钙离子产生胞浆内钙峰，从而产生钙离子诱导的钙脉冲，这些脉冲主要来自靠近质膜的池。
The effects of acetylcholine (ACh), cholecystokinin (CCK), internally applied GTP-.gamma.-S, inositol trisphosphate [Ins (1,4,5) P3] or Ca2+ on the cytoplasmic free Ca2+ concentration ([Ca2+]i) were assessed by simultaneous microfluorometry (fura-2) and measurement of the Ca2+-dependent Cl- current (patch-clamp whole-cell recording) in single internally perfused mouse pancreatic acinar cells. ACh (0.1-0.2 .mu.M) evoked an oscillating increase in [Ca2+]i measured in the cell as a whole (microfluorometry) which was synchronous with oscillations in the Ca2+-dependent Cl- current reporting [Ca2+]i close to the cell membrane. In the same cells a lower ACh concentration (0.05 .mu.M) evoked shorter repetitive Cl-current pulses that were not accompanied by similar spikes in the microfluorimetric recording. When cells did not respond to 09.1 .mu.M ACh, caffeine (1 mM)added on top of the sustained ACh stimulus resulted in [Ca2+]i oscillations seen synchronously in both types of recording. CCK (10 nM) also evoked [Ca2+]i oscillations, but with much longer intervals between slightly broader Ca2+ pulses. Internal perfusion with 100 .mu.M GTP-.gamma.-S evoked [Ca2+]i oscillations with a simialr pattern. Ins (1,4,5) P3 (10 .mu.M) evoke dreptitive shortlasting spikes in [Ca2+]i that were only seen in the Cl- current traces, except in one small cell where thse spikes were also boserved synchronously in the microfluorimetric recording. Caffeine (1 mM) broadened these Ca2+ pulses. [Ca2+]i was also directly changed, bypassing the normal signalling process, by infusion of a low or high Ca2+ solution into the pipette. The relative smooth rise and fall in [Ca2+]i seen inthe microfluorimetric recordings in response to a 3 min Ca2+ infusion were accompanied by a similar rise and fall in the Cl- current. Before the peak and in the following falling phase repetitive short-lasting Cl- current spikes occurred. We conclude that receptor stimulation generates cytoplasmic Ca2+ spikes by Ins (1,4,5) P3-evoked Ca2+ rlease cuasing pulses of Ca2+-induced Ca2+ rlease primarily from pools close to the plasma membrane.