Efferent inhibition of carotid body chemoreception in chronically hypoxic cats.
Efferent inhibition of carotid body chemoreception in chronically hypoxic cats.
复制标题
慢性缺氧猫颈动脉体化学感受的传出抑制。
DOI：
10.1152/ajpregu.1983.245.5.r678
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Mokashi,A
中科院分区：
文献类型：
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作者：
Lahiri,S;Smatresk,N;Pokorski,M;Barnard,P;Mokashi,A
本文用暴露于10%O_2 21-49天的猫，观察了慢性低氧对颈动脉窦神经（CSN）切断前后颈动脉化学感受器传入活动的影响。为了比较，还研究了海平面长期含氧量正常的猫。将猫麻醉，制备用于测量来自CSN小块的颈动脉化学感受活性的少纤维准备，并在恒定PaCO 2下测量其对4-5个动脉压O2（PaO 2）水平的稳态反应，并在切下CSN之前和之后测量高氧下对3-4个PaCO 2水平的稳态反应。慢性暴露于缺氧后，完整CSN的猫对缺氧的化学感受性反应相对于在海平面呼吸室内空气的猫没有减少。切断CSN显著增强了慢性低氧猫对低氧的化学感受性反应，但在常氧猫中不显著。在高氧期间，通过切断两组中的CSN，对中度高碳酸血症的反应没有显著改变。我们的结论是，有一个显着的CSN传出抑制的化学感受活性，由于慢性缺氧的猫。这意味着，如果没有传出抑制缺氧的化学敏感性增加慢性缺氧。
The effects of chronic hypoxia on carotid chemoreceptor afferent activity before and after sectioning the carotid sinus nerves (CSN) were studied in cats exposed to 10% O2 for 21–49 days in a chamber at sea level. For comparison, chronically normoxic cats at sea level were also studied. The cats were anesthetized, paucifiber preparation for the measurement of carotid chemosensory activity from a small slip of CSN was made, and their steady-state responses to 4–5 levels of arterial pressure of O2 (PaO2) at a constant PaCO2 and to 3–4 levels of PaCO2 in hyperoxia were measured before and after sectioning the CSN. The chemosensory response to hypoxia in the cats with intact CSN after chronic exposure to hypoxia was not reduced relative to the cats that breathed room air at sea level. Sectioning the CSN significantly augmented the chemosensory responses to hypoxia in all the chronically hypoxic but not significantly in the normoxic cats. The responses to moderate hypercapnia during hyperoxia were not significantly changed by cutting the CSN in either group. We conclude that there is a significant CSN efferent inhibition of chemosensory activity due to chronic hypoxia in the cat. This implies that without the efferent inhibition the hypoxic chemosensitivity is increased by chronic hypoxia.