purinergic 激动剂通过3型氨酸受体增加了老鼠结膜杯细胞中的[Ca2+]i
Haakon K Fjaervoll1,2,3,4, Ketil A Fjaervoll1,2,3,4, Menglu Yang2
1Division of Head, Neck and Reconstructive Surgery, Faculty of Medicine, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
American journal of physiology. Cell physiology
|August 5, 2024
概括
腺三酸盐 (ATP) 和基基基酸盐 (BzATP) 触发结膜杯细胞 (CGCs) 中的内质网膜释放. 瑞诺丁受体 (RyRs) 被确定为不可刺激细胞中这种信号通路的关键调节者.
科学领域:
- 细胞生物学 细胞生物学
- 身体生理学 身体生理学
- 生物化学 生化学
背景情况:
- 结膜杯细胞 (CGCs) 在对腺三酸盐 (ATP) 和基基酸盐 (BzATP) 的反应中分泌素.
- 由于CGC中ATP和BzATP诱导的细胞内增加 ([Ca2+]i) 的确切来源和调节机制尚不清楚.
- 了解信号对于涉及不可刺激细胞的疾病至关重要.
研究的目的:
- 为了研究细胞内 ([Ca2+]i) 的起源,由ATP和BzATP在结膜杯细胞 (CGC) 中调动.
- 阐明特定离子通道和信号通路在ATP和BzATP介导的释放中的作用.
- 为了确定非刺激性CGCs中的平衡的潜在调节者.
主要方法:
- 主要培养的老鼠CGC被载入Fura-2/AM用于细胞内 ([Ca2+]i) 的测量.
- 在各种预处理条件下,用ATP和BzATP刺激细胞,包括化 (EGTA),内分泌网膜 (ER) 储量耗尽 (thapsigargin) 和脂酶C (PLC) 抑制剂,蛋白激酶A (PKA),电压通道 (nifedipine) 和氨酸受体 (RyRs; dantrolene).
- 使用免疫光显微镜 (IF) 和定量逆转录聚合酶链反应 (RT-qPCR) 来检测老鼠和人类CGC中的RyR表达.
主要成果:
- 在EGTA的无缓冲中,ATP刺激的峰值[Ca2+]i显著降低.
- 服用thapsigargin,PKA抑制剂 (H89),nifedipine和dantrolene的预化显著降低了ATP和BzATP诱导的[Ca2+]i增加,而PLC抑制剂没有显著影响.
- 瑞诺丁受体3 (RyR3) 通过IF和RT-qPCR在老鼠和人类的CGC中被检测到,而高度的丹托诱导了细胞死亡.
结论:
- 在CGC中,ATP和BzATP诱导的细胞内 ([Ca2+]i) 的增加源自内细胞网膜 (ER) 储存.
- 蛋白激酶A (PKA),电压通道和氨酸受体 (RyRs),特别是RyR3,在调节不可刺激的CGC中的[Ca2+]i中起着至关重要的作用.
- 这项研究突显了RyRs在非刺激细胞内的稳定中的重要性,为相关疾病机制提供了洞察力.
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