Mechanisms of receptor-operated Ca^<2+> entry-Molecular structures and the function of store-operated Ca^<2+>entry and its blockers.

受体操纵的Ca ^ 2 进入的机制和钙池操纵的Ca ^ 2 进入及其阻断剂的分子结构和功能。

• 批准号: 11470392
• 负责人: DOHI Toshihiro
• 金额: $ 9.28万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11470392/
• 关键词: Store-operted Ca^<2+> entry; SOC; ROC; trp; calcium; PACAP; PAF; caffeine; Store-operated Ca^<2+> channel; Ca^<2+> チャンネル

The receptor-activated Ca^<2+> channels (ROC) activate Ca^<2+> entry which is activated by the depletion of intracellular Ca^<2+> stores, termed store-operated channels (SOC). However, the structure and function of these channels are still unidentified, and the specific blockers are not developed. The present study was undertaken to elucidate the mechanisms for the activation of and the signal transduction relate to ROC/SOC, and inhibitors for the channels.1 COS cells were expressed with rat TRP by introducing rtrp3 and rtrp6. These COS cells were treated with thapsigargin in the absence of extracellular Ca^<2+> to acivate SOC.Large Ca^<2+> entry was observed in these cells. PC12 cells expressed dominantly trp1 and trp3. In PC12 cells introduced trp1,3 antisense mRNA, Ca^<2+> entry evoked by the pre-treatment of acetylcholine and thapsigargine was enhanced. These results may suggest that TRPs do not simply compose the Ca^<2+> channel itself but relate somehow with SOC systems.2 12-hydr … More oxyeicosatetraenoic acid (12-HETE), a mediator of inflammation. activates neutrophils through the rise of intracellular free Ca^<2+> concentration ([Ca^<2+>]i). However, the mechanism of Ca^<2+> rise was not evident. 12-HETE-induced [Ca^<2+>]i rise was blocked by platelet-activating factor(PAF) antagonist, PAF synthesis inhibitor and 12-HETE stimulated PAF production in human and rabbit neutophils. These results suggested that 12-HETE-induced [Ca^<2+>]i rise is mediated by PAF.FMLP-but not LTB_4-induced [Ca^<2+>]i rise was partly mediated by PAF.3 Pituitary adenylate cyclase activating polypeptide (PACAP) induced long-lasting increase in [Ca^<2+>]i and catecholamine release from bovine adrenal chromaffin cells. PACAP-induced ([Ca^<2+>]i rise was not mediated by cyclic AMP, phospholipase C, cyclic ADP-ribose, voltage-dependent Na+ channels, voltage-dependent Ca^<2+> channels. Pre-activation of SOC did not modify PACAP-induced Ca^<2+> entry. GdCl_2 blocked SOC but did not affect PACAP-induced Ca^<2+> entry. These results suggested that PACAP activates ROC which is distinguishable form SOC.4 Caffeine and theophylline were found to block [Ca^<2+>]i rise and Ca^<2+> entry induced by acetylcholine, thapsigargine and TPEN in bovine adrenal chromaffin cells. Less

受体激活的Ca^<2+>通道（ROC）激活Ca^<2+>通道，该通道通过细胞内Ca^<2+>存储的耗尽而激活，称为存储操作通道（SOC）。然而，这些通道的结构和功能仍然不明，特异性阻滞剂也没有开发出来。本研究旨在阐明与ROC/SOC相关的信号转导的激活机制，以及这些通道的抑制剂通过引入rtrp3和rtrp6，用大鼠TRP表达COS细胞。在缺乏细胞外Ca^<2+>的情况下，用thapsignarin处理这些COS细胞以激活SOC。在这些细胞中观察到大量Ca^<2+>的进入。PC12细胞主要表达trp1和trp3。在引入trp1,3反义mRNA的PC12细胞中，乙酰胆碱和thapsigarine预处理诱发的Ca^<2+>进入增强。这些结果可能表明，trp不仅仅是Ca^<2+>通道本身的组成，而是与SOC系统有某种联系。更多的氧二碳四烯酸（12-HETE），炎症介质。通过细胞内游离Ca^<2+>浓度的升高激活中性粒细胞（[Ca^<2+>]i）。但Ca^<2+>升高的机理尚不清楚。12-HETE诱导的[Ca^<2+>]i升高可被血小板活化因子（PAF）拮抗剂、PAF合成抑制剂和12-HETE刺激的人和兔嗜中性粒细胞中PAF的产生阻断。这些结果表明，12- hete诱导的[Ca^<2+>]i升高是由PAF介导的。垂体腺苷酸环化酶激活多肽（PACAP）诱导牛肾上腺染色质细胞[Ca^<2+>]i和儿茶酚胺释放持续增加。pacap诱导的[Ca^<2+>]i升高不受环AMP、磷脂酶C、环adp核糖、电压依赖性Na+通道、电压依赖性Ca^<2+>通道介导。预激活的SOC没有改变pacap诱导的Ca^<2+>入口。GdCl_2阻断了SOC，但不影响pacap诱导的Ca^<2+>入口。结果表明，PACAP可激活与soc4不同的ROC。咖啡因和茶碱可阻断乙酰胆碱、thapsigarine和TPEN诱导的[Ca^<2+>]升高和Ca^<2+>进入牛肾上腺染色质细胞。少

项目成果

K.Shibata,H.Yoshino,N.Mizuno,H.Shinohara,K.Morita,S.Kitayama,H.Kurihara,T.Dohi: "Mediation by platelet-activating factor of 12-hydroxyeicosatetraenoic acid-induced cytosolic free calcium concentration elevation in neutorphils."Prostaglandins & other Lipid

K.Shibata，H.Yoshino，N.Mizuno，H.Shinohara，K.Morita，S.Kitayama，H.Kurihara，T.Dohi：“血小板活化因子对 12-羟基二十碳四烯酸诱导的胞质游离钙浓度的调节

森田克也: "Ca^<2+>動員物質サイクリックADPリボースの合成酵素および細胞膜輸送体としてのCD38"ファルマシア. 35. 946-947 (1999)

Katsuya Morita：“CD38作为Ca 2+ 动员物质环ADP核糖的合酶和细胞膜转运蛋白”Pharmacia 35. 946-947 (1999)。

森田克也: "Ca^<2+>動員物質サイクリックADPリボースの合成および細胞膜輸送体としてのCD38"ファルマシア. 35. 946-947 (1999)

Katsuya Morita：“Ca 2+ 动员物质环ADP核糖和CD38作为细胞膜转运蛋白的合成”Pharmacia 35. 946-947 (1999)。

Shibata, K., Yoshino, H., Mizuno, N., Shinohara, H., Morita, K., Kitayama, S., Kurihara, H.and Dohi, T.: "Mediation of platelet-activating factor of 12-hydroxyeicosatetraenoic acid-induced cytosolic free calcium concentration elevation in neutrophils."Pro

Shibata, K.、Yoshino, H.、Mizuno, N.、Shinohara, H.、Morita, K.、Kitayama, S.、Kurihara, H. 和 Dohi, T.：“12-血小板活化因子的介导

Morita, K.: "CD38 as an enzyme for the synthesis of cyclic ADP-ribose, an endogenous Ca^<2+> mobilizing substance and for the transmembrane carrier of the nucleotide."Farumashia. 35. 946-947 (1999)

Morita, K.：“CD38作为一种酶，用于合成环状ADP-核糖、一种内源性Ca 2+ 动员物质以及核苷酸的跨膜载体。”Farumashia。