DAG lipase-lipoxygenase pathway in Ca sensing of parathyroid cells

甲状旁腺细胞 Ca2+ 感应中的 DAG 脂肪酶-脂氧合酶途径

• 批准号: 20570073
• 负责人: OKADA Yukio
• 金额: $ 3.08万
• 依托单位: Nagasaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2008
• 资助国家: 日本
• 起止时间: 2008 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20570073/
• 关键词: 動物生理化学; 細胞シグナル伝達; 副甲状; アラキドン酸; Ca^<2+>; パッチクランプ; ウシガエル; イオンチャネル; 情報伝達; Gタンパク質

Elevation of extracellular Ca^<2+> concentration induces intracellular Ca^<2+> signaling in parathyroid cells. We report the electrophysiological property associated with intracellular Ca^<2+> signaling in frog parathyroid cells and show that Ca^<2+>-activated Cl- channels are activated by intracellular Ca^<2+> increase through inositol 1,4,5-trisphophate (IP3)-independent pathway. High extracellular Ca^<2+> induced an outwardly-rectifying conductance in a dose-dependent manner. The conductance was composed of an instantaneous time-independent component and a slowly activating time-dependent component and displayed deactivating inward tail current. Extracellular Ca^<2+>-induced and Ca^<2+> dialysis-induced currents reversed at the equilibrium potential of Cl- and were inhibited by niflumic acid. Extracellular Ca^<2+>-induced currents displayed a moderate dependency on guanosine triphosphate (GTP). All blockers for phospholipase C, DAG lipase, MAG lipase and lipoxygenase inhibited extracellular Ca^<2+>-induced current. IP3 dialysis failed to induce conductance increase, but 2-AG, arachidonic acid and 12(S)-HPETE dialysis increased the conductance identical to extracellular Ca^<2+>-induced conductance. These results indicate high extracellular Ca^<2+> raises intracellular Ca^<2+> concentration through DAG lipase/lipoxygenase pathway, resulting in the activation of Cl^-conductance.

甲状旁腺细胞胞外钙离子浓度升高可诱导细胞内钙离子信号转导。我们报道了青蛙甲状旁腺细胞内钙离子信号转导的电生理特性，表明细胞内钙离子激活的氯离子通道是通过不依赖于三磷酸肌醇(IP3)的途径增加的。细胞外高Ca~(2+)和Gt~(2+)以剂量依赖方式诱导外向整流电导。电导由瞬时时变分量和慢激活时变分量组成，表现为失活的内向尾流。细胞外Ca~(2+)和Ca~(2+)-Gt~(2+)透析诱发的电流在Cl-的平衡电位处发生翻转，并被尼氟米酸抑制。胞外Ca~(2+)诱导的电流对鸟苷三磷酸(GTP)有一定的依赖性。磷脂酶C、DAG脂肪酶、MAG脂肪酶和脂氧合酶的阻断剂均可抑制细胞外钙离子诱导的电流。IP3透析不能引起电导增加，但2-AG、花生四烯酸和12(S)-HPETE透析增加的电导与细胞外Ca~(2+)&Gt；这些结果表明，细胞外高钙通过DAG脂肪酶/脂氧合酶途径增加细胞内钙离子浓度，从而激活细胞内的氯离子电导。

项目成果

カエル副甲状腺のアラキドン酸誘発電流

花生四烯酸诱导青蛙甲状旁腺电流

• 发表时间: 2010
• 作者: 岡田幸雄;他
• 通讯作者: 他

Ice cube stimulation helps to improve dysgusia.

冰块刺激有助于改善味觉障碍。

• 发表时间: 2010
• 期刊: Odontology 98(1)
• 作者: Fujiyama R;Ishitobi S;Honda K;Okada Y;Oi K;Toda K
• 通讯作者: Toda K

Electrical properties and gustatory responses of various taste disk cells of frog fungiform papillae

蛙菌状乳头各种味盘细胞的电特性和味觉反应

• 发表时间: 2008
• 期刊: Chem. Senses 33
• 作者: Sato;T.;et al.
• 通讯作者: et al.

The receptor potential of frog taste cells in response to cold and water stimuli.

青蛙味觉细胞对寒冷和水刺激的感受器电位。

• 发表时间: 2010
• 期刊: Chem Senses 35(6)
• 作者: Sato T;Nishishita K;Okada Y;Toda K
• 通讯作者: Toda K

Involvement of PTK-MAPK cascade in extracellular calcium-sensing of frog parathyroid cells

PTK-MAPK级联参与青蛙甲状旁腺细胞的细胞外钙感应

• 发表时间: 2009
• 作者: Okada;Y.;et al.
• 通讯作者: et al.