Coordinated intercellular calcium waves induced by noradrenaline in rat hepatocytes: dual control by gap junction permeability and agonist
Coordinated intercellular calcium waves induced by noradrenaline in rat hepatocytes: dual control by gap junction permeability and agonist
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大鼠肝细胞去甲肾上腺素诱导的协调细胞间钙波：间隙连接通透性和激动剂的双重控制
作者：
T. Tordjmann;B. Berthon;M. Claret;L. Combettes
钙动员激动剂诱导细胞内Ca 2+浓度（[Ca 2 +]i）变化，被认为是触发细胞反应。在连接的细胞中，[Ca 2 +]i的升高可以作为细胞间Ca 2+波在细胞间传播，其机制尚未阐明。使用负载fura 2的大鼠肝细胞，我们研究了控制去甲肾上腺素诱导的Ca 2+信号的协调和细胞间传播的机制。用18 α-大黄酸阻断缝隙连接导致连接细胞之间失去协调。我们发现，第二信使和[Ca 2 +]i上升，在一个肝细胞不能触发Ca 2+反应连接的细胞，这表明跨间隙连接的扩散，而需要协调，是不足以本身的细胞间Ca 2+波的传播。此外，我们的实验揭示了连接的肝细胞中去甲肾上腺素诱导的Ca 2+信号之间的功能差异。这些结果表明，在大鼠肝细胞的多细胞系统的细胞间Ca 2+信号的传播和高度组织通过复杂的机制，涉及至少三个因素。首先，间隙连接偶联确保了不同细胞之间[Ca 2 +]i振荡的协调;其次，每个肝细胞中激素的存在是细胞间Ca 2+信号传播所必需的;第三，相邻连接的肝细胞之间的功能差异可能允许Ca 2+波的“起搏器样”细胞间传播。
Calcium‐mobilizing agonists induce intracellular Ca2+ concentration ([Ca2+]i) changes thought to trigger cellular responses. In connected cells, rises in [Ca2+]i can propagate from cell to cell as intercellular Ca2+ waves, the mechanisms of which are not elucidated. Using fura2‐loaded rat hepatocytes, we studied the mechanisms controlling coordination and intercellular propagation of noradrenaline‐induced Ca2+ signals. Gap junction blockade with 18 α‐glycyrrhetinic acid resulted in a loss of coordination between connected cells. We found that second messengers and [Ca2+]i rises in one hepatocyte cannot trigger Ca2+ responses in connected cells, suggesting that diffusion across gap junctions, while required for coordination, is not sufficient by itself for the propagation of intercellular Ca2+ waves. In addition, our experiments revealed functional differences between noradrenaline‐induced Ca2+ signals in connected hepatocytes. These results demonstrate that intercellular Ca2+ signals in multicellular systems of rat hepatocytes are propagated and highly organized through complex mechanisms involving at least three factors. First, gap junction coupling ensures coordination of [Ca2+]i oscillations between the different cells; second, the presence of hormone at each hepatocyte is required for cell‐cell Ca2+ signal propagation; and third, functional differences between adjacent connected hepatocytes could allow a ‘pacemaker‐like’ intercellular spread of Ca2+ waves.
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间隙连接通讯调节胰腺腺泡中的 [Ca2]i 振荡和酶分泌。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Stauffer,PL;Zhao,H;Luby-Phelps,K;Moss,RL;Star,RA;Muallem,S
通讯作者：
Muallem,S
DOI：
10.1016/s0021-9258(18)71469-5
发表时间：
1989-10
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
T. A. Rooney;E. J. Sass;A. P. Thomas
通讯作者：
T. A. Rooney;E. J. Sass;A. P. Thomas
离体大鼠肝细胞对中激素诱导的钙信号的协调：共聚焦显微镜演示。
影响因子：
3.3
作者：
Nathanson,MH;Burgstahler,AD
通讯作者：
Burgstahler,AD
肌醇1,3,4,5-四磷酸在肝脏中的形成和代谢。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Hansen,CA;Mah,S;Williamson,JR
通讯作者：
Williamson,JR
DOI：
10.1016/s0021-9258(18)51566-0
发表时间：
1989-08
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
T. Kawanishi;L. Blank;A. Harootunian;M. Smith;R. Tsien
通讯作者：
T. Kawanishi;L. Blank;A. Harootunian;M. Smith;R. Tsien