Interactions between hypoxia and hypercapnic acidosis on calcium signaling in carotid body type I cells
Interactions between hypoxia and hypercapnic acidosis on calcium signaling in carotid body type I cells
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DOI：
10.1152/ajplung.2000.279.1.l36
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发表时间：
2000-07-01
影响因子：
4.9
通讯作者：
Vaughn-Jones, RD
中科院分区：
文献类型：
--
作者：
Dasso, LLT;Buckler, KJ;Vaughn-Jones, RD
用Indo 1测定了高碳酸酸中毒和缺氧对新生大鼠颈动脉体I型细胞内Ca ~（2+）浓度（[Ca ~（2+）]（i））的影响。I型细胞对分级缺氧刺激的反应是[Ca 2 +]（i）分级升高。细胞反应的百分比也取决于缺氧刺激的严重程度。将CO2从5%提高到10%或20%会导致与对缺氧有反应的细胞相同的细胞中[Ca 2 +]（i）显着增加。因此，这两种刺激都可以被每个单独的细胞感知到。当同时给予低氧和酸性刺激的组合时，反应总是大于对单独给予的任一刺激的反应。事实上，在大多数情况下，对高碳酸血症的反应因缺氧而略有增强。这些数据提供了第一个证据表明，在完整的颈动脉体中观察到的缺氧和高碳酸刺激之间的经典协同作用可能部分是I型细胞的固有特性。
The effects of hypercapnic acidosis and hypoxia on intracellular Ca2+ concentration ([Ca2+](i)) were determined with Indo 1 in enzymatically isolated single type I cells from neonatal rat carotid bodies. Type I cells responded to graded hypoxic stimuli with graded [Ca2+](i) rises. The percentage of cells responding was also dependent on the severity of the hypoxic stimulus. Raising CO2 from 5 to 10 or 20% elicited a significant increase in [Ca2+](i) in the same cells as those that responded to hypoxia. Thus both stimuli can be sensed by each individual cell. When combinations of hypoxic and acidic stimuli were given simultaneously, the responses were invariably greater than the response to either stimulus given alone. Indeed, in most cases, the response to hypercapnia was slightly potentiated by hypoxia. These data provide the first evidence that the classic synergy between hypoxic and hypercapnic stimuli observed in the intact carotid body may, in part, be an inherent property of the type I cell.