Mechanism underlying the spontaneous changes in the cytosolic CaィイD12+ィエD1concentrations in rat adrenal chromaffin cells

大鼠肾上腺嗜铬细胞胞质 CaD12+D1 浓度自发变化的机制

• 批准号: 10670045
• 负责人: SORIMACHI Masaru
• 金额: $ 1.98万
• 依托单位: Kagoshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10670045/
• 关键词: Mouse adrenal medulla; the cytosolic CaィイD12+ィエD1concentration; confocal microscope; Oregon-green-BAPTA-1; ATP; gap-junction; lucifer yellow; Rhodamine green dextran; ロダミン-グリーン-デキストラン; 共焦点レーザ顕微鏡; ネズミ副腎髄質; オレゴングリーンBAPTA-1

The spontaneous fluctuations of the cytosolic CaィイD12+ィエD1 concentrations ([Ca]ィイD2inィエD2) have often been observed in isolated single rat adrenal chromaffin cells. To see whether these [Ca]ィイD2inィエD2 changes occur also in vivo, we measured [Ca]ィイD2inィエD2 in individual chromaffin cells involved in adrenal slice preparations after loading with Oregon-green-BAPTA-1/AM. We often observed the spontaneous changes in [Ca]ィイD2inィエD2 when measured with cofocal laser-scanning microscope. In addition, we found that the spontaneous [Ca]ィイD2inィエD2 increase immediately spreads to the neighboring cells in some cases. The synchronization of [Ca]ィイD2inィエD2 increases among the neighboring cells occurs more frequently in mouse adrenal medullary slice preparations, where the gap-junction has been shown to exist. Treatment of mouse adrenal slices with the ATP receptor antagonist PPADS did not inhibit the spread of CaィイD12+ィエD1 signals, and ATP increased [Ca]ィイD2inィエD2 in only 30% of isolated cells tested, suggesting that ATP released from the cells is not responsible for the excitation of the neighboring cells. We also investigated the effects of the inhibitors of gap-junctions on the spread of CaィイD12+ィエD1 signals, but these agents markedly inhibited the occurrence of the spontaneous [Ca]ィイD2inィエD2 increase. However, the combined loading of Lucifer yellow and Rhodamine green dextran-70000 into the cells through the damaged membrane revealed that the distribution pattern of the former agent, which passes through the gap-junctions, was broader than that of the latter. These results suggest that the synchronized [Ca]ィイD2inィエD2 changes among cells were mediated by the gap junctions between the cells.

在分离的大鼠肾上腺嗜铬细胞中，常可观察到胞浆内[Ca]ィイD12+ィエD1浓度([Ca]ィイD2 inィエD2)的自发波动。为了了解这些[Ca]ィイD2在ィエD2中的变化是否也在体内发生，我们测量了在加载俄勒冈绿-BAPTA-1/AM后，参与肾上腺切片制备的单个嗜铬细胞中的[Ca]ィイD2在ィエD2中的变化。激光共聚焦扫描显微镜测量时，常可观察到ィイD2中[Ca]ィエD2的自发变化。此外，我们还发现，在某些情况下，ィイD2中自发增加的[Ca]ィエD2会立即扩散到邻近细胞。在小鼠肾上腺髓质切片制片中，[Ca]ィイD2在ィエD2中的同步性增加在相邻细胞之间发生得更频繁，在那里已经被证明存在缝隙连接。用三磷酸腺苷受体拮抗剂PPADS处理小鼠肾上腺切片，并不能抑制CaィイD12+ィエD1信号的扩散，而三磷酸腺苷只使30%的分离细胞中的[Ca]ィイD2增加，这表明细胞释放的三磷酸腺苷不是引起邻近细胞兴奋的原因。我们还研究了缝隙连接抑制剂对CaィイD12+ィエD1信号扩散的影响，但这些药物显著抑制了[Ca]ィイD2在ィエD2增加中的自发发生。然而，荧光黄和罗丹明绿葡聚糖-70000通过受损的细胞膜进入细胞的联合负载表明，前者通过缝隙连接的分布模式比后者更广泛。这些结果表明，细胞间[Ca]ィイD2在ィエD2中的同步变化是由细胞间的缝隙连接介导的。

项目成果

K,Ymagami,S,Nishimura,etal: "Cd^<2+>and Co^<2+> at miaromoar concentrations mobilige intra"Brain Resoarch. 798. 316-319 (1998)

K，Ymagami，S，Nishimura，等人：“Cd ^ 2 >和Co ^ 2 >在微小浓度下在脑内流动”Brain Resoarch。

Sorimachi,M.Nishimura,S and Yamagami,K.: "Sequestration of clepdsrijation-induced Ca^<2+> loack by mHochonelria and Ca^<2+> effux via mitochondrial Na^+/Ca^<2+> exchanger in bovine chromaffincells" Japanese J.of Physiology. (in press).

Sorimachi,M.Nishimura,S 和 Yamagami,K.：“牛嗜铬细胞中 mHochonelria 封存 clepdsrijation 诱导的 Ca^<2> loack 和 Ca^<2> 通过线粒体 Na^/Ca^<2> 交换器流出”日语

Yamagami,K.,Nishimura,S.Sorimachi,M: "Cd and Co at micromolar concenlnations mobilige intracellutar Ca^<2+> via the generation of inosutol 1,4,5-triphoqhate in bovine dnomaffin cells" Brain Research. 798. 316-319 (1998)

Yamagami,K.,Nishimura,S.Sorimachi,M：“微摩尔浓度的 Cd 和 Co 通过在牛 dnomaffin 细胞中生成肌醇 1,4,5-三磷酸盐而动员细胞内 Ca^2””脑研究。

M,Sorimachi,K.Yamagami,etal: "Excitatory effect of Cd^<2+> on cat odrenal chromaffin cells"Brain Research. 9832. 23-30 (1999)

M，Sorimachi，K.Yamagami，等人：“Cd^2>对猫肾上腺嗜铬细胞的兴奋作用”脑研究。

M.Sorimachi,S.Nishimura etal: "Seqribstratio of depolarization-induced Ca^<2+> loads by Mt"Jap.T.physioLogy. 49. 35-46 (1999)

M.Sorimachi、S.Nishimura 等人：“Mt 去极化诱导的 Ca^2 > 负载的 Seqribstratio”Jap.T.physioLogy。