Detection of hypoxia-evoked ATP release from chemoreceptor cells of the rat carotid body
Detection of hypoxia-evoked ATP release from chemoreceptor cells of the rat carotid body
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DOI：
10.1016/j.bbrc.2004.07.081
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发表时间：
2004-09-10
影响因子：
3.1
通讯作者：
Nurse, CA
中科院分区：
文献类型：
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作者：
Buttigieg, J;Nurse, CA
颈动脉体（CB）是一种化学感受器官，检测动脉血化学成分的变化，并通过通气的反射控制来维持体内平衡。因此，在响应动脉PO 2（缺氧）的下降，CB化学感受器（I型细胞）去极化，并释放神经递质到传入感觉神经末梢。最近的研究表明，ATP是CB化学兴奋过程中释放的一种关键兴奋性神经递质，但缺乏直接证据。在这里，我们使用荧光素-荧光素酶生物发光试验来检测CB培养物、新鲜组织切片和整个CB中大鼠化学感受器释放的ATP。缺氧引起的细胞外ATP的增加，这是抑制L-型钙通道阻滞剂和减少的核苷水解酶，腺苷三磷酸双磷酸酶。此外，伊比利亚毒素（IbTX; 100 nM），O-2-敏感的Ca 2+依赖性K+（BK）通道的阻断剂，刺激ATP释放，并在很大程度上阻断缺氧的影响。这些数据强烈支持ATP在颈动脉体功能中的神经递质作用。(C)2004爱思唯尔公司All rights reserved.
The carotid body (CB) is a chemosensory organ that detects changes in chemical composition of arterial blood and maintains homeostasis via reflex control of ventilation. Thus, in response to a fall in arterial PO2 (hypoxia), CB chemoreceptors (type I cells) depolarize, and release neurotransmitters onto afferent sensory nerve endings. Recent studies implicate ATP as a key excitatory neurotransmitter released during CB chemoexcitation, but direct evidence is lacking. Here we use the luciferin-luciferase bioluminescence assay to detect ATP, released from rat chemoreceptors in CB cultures, fresh tissue slices, and whole CB. Hypoxia evoked an increase in extracellular ATP, that was inhibited by L-type Ca2+ channel blockers and reduced by the nucleoside hydrolase, apyrase. Additionally, iberiotoxin (IbTX; 100 nM), a blocker of O-2-sensitive Ca2+-dependent K+ (BK) channels, stimulated ATP release and largely occluded the effect of hypoxia. These data strongly support a neurotransmitter role for ATP in carotid body function. (C) 2004 Elsevier Inc. All rights reserved.