Analysis of functional role of capacitative Ca entry in enteric neurons

肠神经元电容性 Ca 进入的功能作用分析

• 批准号: 13660292
• 负责人: OHTA Toshio
• 金额: $ 2.18万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13660292/
• 关键词: Calcium; enteric neurons; adrenal chromaffin cells; transient receptor potential protein; ion channel; intracellular calcium; タプシガルジン; 細胞内ストア; クロム親和性細胞; PC12細胞; オピオイドペプチド; 電位依存性Caチャネル; ミトコンドリア; TRP

The main aim of this project was to clarify the regulatory role of capacitative Ca entry mechanisms in enteric neurons. For this purpose the properties of Ca influx pathways and their regulation were examined using chromaffin and PC12 cells as neural models, and cultured enteric neurons. 1) Voltage-dependent Ca channels in chromaffin cells were received an inhibitory control through G-proteins by endogenous opioids. 2) Ca release from the intracellular stores regulated the activity of membrane ionic channels as well as secretory responses. 3) ATP evoked [Ca^<2+>]I increase in enteric neural cells with anti-PGP 9.5-immunoreactivity. After intracellular stored Ca was depleted with ATP and thapsigargin, a sustained [Ca^<2+>]I was produced, which was suppressed by the treatment with SK&F96365, Ni^<2+> and La^<3+>, indicating that the presence of capacitative Ca entry in enteric neuronal cells. 5) RT-PCR revealed that several TRP-proteins, being considered as Ca entry pathways, were expressed in rat brain and enteric neurons. 5) In TRP5-transfected PC12 cells, [Ca^<2+>]I increases induced by stimulation of G-protein coupled receptors such as bradykinin and UTP were significantly larger than those in mock-cells. These results indicate that Ca entry pathways in neural cells were regulated under various mechanisms, and capacitive Ca entry mechanisms play a role as Ca influx pathway stimulated by the neurotransmitters in enteric neurons. Further research is necessarily to elucidate the molecular basis of the channels protein and intracellular regulatory mechanism on capacitative Ca entry in enteric neural cells.

本项目的主要目的是阐明肠神经元中的容量性钙内流机制的调节作用。为此目的，使用嗜铬细胞和PC 12细胞作为神经模型，并培养肠神经元，检查Ca内流途径的特性及其调节。1)嗜铬细胞电压依赖性钙通道受内源性阿片类药物通过G蛋白的抑制性调控。2)细胞内钙库的钙释放调节膜离子通道的活性以及分泌反应。3)ATP诱发抗PGP 9.5免疫反应性肠神经细胞[Ca^<2+>]I增加。用ATP和毒胡萝卜素耗竭细胞内储存的Ca后，产生持续的[Ca^<2+>]I，而用SK &F96365、Ni^<2+>和La^<3+>处理后，[Ca^<2+>] i被抑制，表明肠神经元细胞中存在容量性Ca内流。5)RT-PCR结果显示，在大鼠脑和肠神经元中有几种被认为是Ca进入通路的TRP蛋白表达。5)在TRP 5转染的PC 12细胞中，刺激G蛋白偶联受体如缓激肽和UTP诱导的[Ca^2+]I增加明显大于模拟细胞。这些结果表明，神经细胞内钙内流途径受多种机制的调控，其中电容性钙内流机制与神经递质刺激的钙内流途径一样发挥作用。进一步的研究有必要阐明通道蛋白的分子基础和肠神经细胞内钙容性内流的调控机制。

项目成果

Ohta T. et al.: "Functional relation between caffeine-and muscarine-sensitive Ca2+stores and no Ca2+ releasing action of cyclic adenosine diphosphate-ribose in guinea-pig adrenal chromaffin cells"Neuroscience Letters. 326. 167-170 (2002)

Ohta T.等人：“豚鼠肾上腺嗜铬细胞中咖啡因和毒蕈碱敏感的Ca2储存与环腺苷二磷酸核糖无Ca2释放作用之间的功能关系”神经科学快报。

Shigeo Ito: "Heterogeneiety of neruronal nicotinic acetylchooine receptors in 5-HT-containing chemoreceptor cells of the chicken aorta"British Journal of Pharmacology. 132. 1934-1940 (2001)

Shigeo Ito：“鸡主动脉含 5-HT 化学感受器细胞中神经元烟碱乙酰胆碱受体的异质性”英国药理学杂志。

Ohta T.: "Functional relation between caffeine-and muscarine-sensitive Ca2+stores and no Ca2+ releasing action of cyclic adenosine diphosphate-ribose in guinea-pig adrenal chromaffin cells"Neuroscience Letters. 326. 167-170 (2002)

Ohta T.：“豚鼠肾上腺嗜铬细胞中咖啡因和毒蕈碱敏感的 Ca2 储存与环腺苷二磷酸核糖无 Ca2 释放作用之间的功能关系”神经科学快报。

Kitamura G.: "Inhibitory effects of opioids on voltage-dependent Ca2+ channels and catecholamine secretion in cultured porcine adrenal chromaffin cells"Brain Research. 942. 11-22 (2002)

Kitamura G.：“阿片类药物对培养的猪肾上腺嗜铬细胞中电压依赖性 Ca2 通道和儿茶酚胺分泌的抑制作用”大脑研究。

Yohei Kasai: "Release of dopamine and ATP from PC12 cells treated with dexamethasone, reserpine and bafilomycin A1"Joural of Veterinary Medical Science. 63. 367-372 (2001)

Yohei Kasai：“用地塞米松、利血平和巴弗洛霉素 A1 处理的 PC12 细胞释放多巴胺和 ATP”《兽医医学杂志》。