Inhibition of ATP-induced calcium influx in HT4 cells by glucocorticoids:involvement of protein kina

来源 :Acta Pharmacologica Sinica | 被引量 : 0次 | 上传用户:libq19811022
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Aim:In our previous observations,adenosine triphosphate(ATP)was found toevoke immediate elevations in intracellular free calcium concentration([Ca~(2+)]_i)in HT4 neuroblastoma cells of mice.We tried to see if a brief pretreatment ofglucocorticoids could inhibit the Ca~(2+)response and reveal the underlying signal-ing mechanism.Methods:Measurement of[Ca~(2+)]_i was carried out using thedual-wavelength fluorescence method with Fura-2 as the indicator.Results:Pre-incubation of HT4 cells for 5 min with corticosterone(B)or bovine serum albu-min conjugated corticosterone(B-BSA)inhibited the peak[Ca~(2+)]_i increments in aconcentration-dependent manner.Cortisol and dexamethasone had a similar action,while deoxycorticosterone and cholesterol were ineffective.Both extracellularCa~(2+)influx and intemal Ca~(2+)release contributed to ATP-induced[Ca~(2+)]_i elevation.The brief treatment with only B attenuated Ca~(2+)influx.Furthermore,the[Ca~(2+)]_ielevation induced by the P2X receptor agonist adenosine 5’-(β,γ-methylene)triph-osphate(β,γ-meATP)was also suppressed.The rapid inhibitory effect of B canbe reproduced by forskolin 1 mmol/L and blocked by H89 20 mmol/L.Neithernuclear glucocorticoid receptor antagonist mifepristone nor protein kinase C in-hibitors influenced the rapid action of B.Conclusion:Our results suggest thatglucocorticoids modulate P2X receptor-medicated Ca~(2+)influx through a mem-brane-initiated,non-genomic and PKA-dependent pathway in HT4 cells. Aim: In our previous observations, adenosine triphosphate (ATP) was found to evoke immediate elevations in intracellular free calcium concentration ([Ca ~ (2 +)] _i) in HT4 neuroblastoma cells of mice. We tried to see if a brief pretreatment of glucocorticoids could inhibit the Ca 2+ response and reveal the underlying signal-ing mechanism. Methods: Measurement of [Ca ~ (2 +)] _i was carried out using thedual-wavelength fluorescence method with Fura-2 as the indicator. Results: Pre-incubation of HT4 cells for 5 min with corticosterone (B) or bovine serum albu-min conjugated corticosterone (B-BSA) inhibited the peak [Ca ~ (2 +)] _ i increments in aconcentration-dependent manner. Cortisol and dexamethasone had a similar action, while deoxycorticosterone and cholesterol were ineffective.Both extracellular Ca ~ (2+) influx and intemal Ca ~ (2+) release contributed to ATP-induced [Ca ~ (2 +)] _i elevation.The brief treatment with only B attenuated Ca ~ (2+) influx.Furthermore, the [Ca ~ (2 +)] _levenvation induced by the P2X receptor agonist address NOSINE 5 ’- (β, γ-methylene) triph-osphate (β, γ-meATP) was also suppressed. The rapid inhibitory effect of B canbe reproduced by forskolin 1 mmol / L and blocked by H89 20 mmol / L.Neithernuclear glucocorticoid receptor antagonist mifepristone nor protein kinase C in-hibitors influenced the rapid action of B. Conlusion: Our results suggest that glucocorticoids modulate P2X receptor-medicated Ca 2+ influx through a mem-brane-initiated, non-genomic and PKA-dependent pathway in HT4 cells.
其他文献
一项国际研究的结果表明,对极高风险的急性成淋巴细胞白血病(ALL)儿童患者而言,来自于捐赠者完全匹配的干细胞移植结果要比化疗结果更为有效。意大利研究人员Adriana Balduz
山海协作工程。“山海协作工程”是省委、省政府为加快欠发达地区经济社会发展而制定实施的,旨在通过发达地区与欠发达地区的联合与合作,在欠发达地区组建一批富有活力的合作
于忠海,男,1958年12月出生,教授,硕士生导师。1982年7月毕业于东北重机学院机械制造工艺与设备专业,1989年9月获得燕山大学机械制造及其自动化专业硕士学位。曾历任东北重机
情感在英语教学中起着非常重要的作用。关注学生的情感不仅促进学生的语言学习,而且有利于学生的身心健康发展,并最终实现素质教育的终极目标—以人为本。本文重在分析三本院
<正>同声传译由于其高效、专业以及会议场合和服务对象的神秘性,从问世起就引起了广泛兴趣。不同学科背景的研究者,从不同的角度来分析同传译员的特质、成长和表现:神经生理
We report a case of a 74-year-old woman with a 16-year history of a double bilo-enteric anastomosis due to resected hilar cholangiocarcinoma [Type Ⅲb Klatskin
In view of the poor prognosis of patients with cholangiocarcinoma (CCC), there is a need for new therapeutic strategies. Inter-disciplinary therapy seems to be
本文提出了设计构件时使构件既安全且经济几项有效措施,即:(1)合理地选择和设计构件截面;(2)根据材料的性能,合理地使用材料,(3)根据构件的受力情况,选择等强度构件.(4)合理地安排构件的束条件.
·专题—旋压成形·国产旋压设备的发展和应用张顺福等 (1,1)…………………空调用过滤瓶数控旋压成形工艺研究夏琴香等 (1,4 )………碟形封头冷旋压成形时的数值分析及旋压
本刊讯 近接湖北省教育厅文件通知 ,湖北大学成教学院学籍管理办公室管理干部谌瑾荣获全省高等教育学历证书电子注册管理工作先进个人称号。据悉 ,自 2 0 0 1年实行高等教育