IP_(3)R与RyR对新生大鼠心肌细胞钙振荡调控的研究  

Regulation of calcium oscillations by IP_(3)R and RyR in neonatal rat cardiomyocytes

作　　者：戚瑛 赵芯仪 姚佳辉 谢文俊 张伊 QI Ying;ZHAO Xinyi;YAO Jiahui;XIE Wenjun;ZHANG Yi(Department of Physiology and Pathophysiology,School of Basic Medical Sciences,Xi’an Jiaotong University Health Science Center,Xi’an 710061;School of Life Science and Technology,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学医学部基础医学院生理学与病理生理学系,陕西西安710061 [2]西安交通大学生命科学与技术学院,陕西西安710049

出　　处：《西安交通大学学报（医学版）》2022年第6期801-806,共6页Journal of Xi’an Jiaotong University（Medical Sciences）

基　　金：国家自然科学基金资助项目(No.11672226,32171103);中央高校基本科研业务费(No.xzy022021057)。

摘　　要：目的拟探讨新生期心肌细胞中肌浆网上两种主要的钙离子释放通道1,4,5-三磷酸肌醇受体(1,4,5-trisphosphate receptors,IP_(3)Rs)及雷诺丁受体(ryanodine receptors,RyRs)对细胞内钙振荡的调节作用。方法以体外培养原代新生SD大鼠心肌细胞为实验材料,通过钙离子指示剂fura-2荧光成像,分别利用IP_(3)Rs及RyRs通道的激动剂phenylephrine(PE)、caffeine,以及抑制剂2-APB和tetracaine作用于细胞,研究这两类通道对细胞内钙振荡信号的影响。结果培养的单层新生大鼠心肌细胞有自发的同步的钙振荡;PE处理使得钙振荡频率增加,而2-APB则抑制胞内钙振荡的频率,但它们对钙振荡幅度无明显影响;caffeine增加钙振荡频率但扰乱细胞跳动节律,而tetracaine则完全抑制心肌细胞的钙振荡信号,使细胞停止跳动。此外,应用PE分别作用于培养3 d、7 d及10 d的新生大鼠心肌细胞后,发现其对钙振荡频率的调增作用随培养时间增加而明显下降。结论新生大鼠心肌细胞内钙振荡频率主要受IP_(3)Rs调节,而RyRs是大量钙离子释放的主要通道,决定钙振荡的幅度。Objective To explore the roles of 1,4,5-trisphosphate receptor(IP_(3)Rs)and ryanodine receptors(RyRs),the two main Ca^(2+)release channels in sarcoplasmic reticulum(SR),in the regulation of intracellular Ca^(2+)oscillations in neonatal rat cardiomyocytes(NRCMs).Methods We isolated and cultured NRCMs for different days,then loaded them with Ca^(2+)indicator fura-2 and performed real-time fluorescent imaging.To distinguish the effects of IP_(3)Rs and RyRs,NRCMs were pre-treated with phenylephrine(PE,IP_(3)Rs agonist),caffeine(RyRs agonist),2-APB(IP_(3)Rs antagonist),and tetracaine(RyRs antagonists),respectively.Results The cultured monolayer NRCMs showed spontaneous synchronized Ca^(2+)oscillations.PE activation or 2-APB blockade of IP_(3)Rs increased or reduced the frequency of Ca^(2+)oscillations in NRCMs,accordingly,with no significant effect on the amplitude of Ca^(2+)oscillations.Activation of RyRs with caffeine increased the frequency of Ca^(2+)oscillations,but unsynchronized the intercellular rhythm of calcium release and beating pace,while blocking RyRs with tetracaine completely abolished the Ca^(2+)oscillations and beats in NRCMs.In addition,the effect of PE stimulation on Ca^(2+)oscillation frequency gradually decreased along with cultured days.Conclusion IP_(3)Rs regulate the rhythm of calcium oscillations,whereas RyRs are the main channel for bulky store Ca^(2+)release.

关 键 词：1 4 5-三磷酸肌醇受体(IP_(3)Rs) 雷诺丁受体(RyR) 新生大鼠 心肌细胞 钙振荡 

分 类 号：R331.3[医药卫生—人体生理学]