Ventrolateral pons mediates short-term depression of respiratory frequency after brief hypoxia
Ventrolateral pons mediates short-term depression of respiratory frequency after brief hypoxia
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DOI：
10.1016/s0034-5687(00)00121-3
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发表时间：
2000-07-01
期刊：
影响因子：
--
通讯作者：
Coles, SK
中科院分区：
文献类型：
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作者：
Dick, TE;Coles, SK
成年麻醉大鼠对缺氧的呼吸反应是动态的。缺氧引起潮气量（VT）和呼吸频率（fR）的急性升高，随后VT短期升高，fR短期降低。短暂缺氧（< 1分钟）后，呼吸模式的恢复再次是动态的，VT和fR立即下降，但VT仍高于基线，fR降至基线以下。这些急性变化之后，VT短期进行性降低，fR升高至基线。我们已经确定了一种潜在的神经机制，它依赖于腹外侧（vl）笔的完整性。我们的研究表明：(a)阻断vl笔的活性可阻止缺氧后fR的短期下降(b)刺激vl笔可降低fR， (c)缺氧后vl脑桥呼吸神经元被激活。这些神经元可能不通过α(2)-肾上腺素能受体起作用，但它们的作用确实依赖于nmda型受体的功能。我们得出结论，vl笔是产生和调节急性缺氧时fR反应的桥髓网络中的一个关键因素。(C) 2000 Elsevier Science B.V.版权所有
The respiratory response to hypoxia is dynamic in the adult anesthetized Sprague-Dawley rat. Hypoxia elicits acute increases in both tidal volume (VT) and respiratory frequency (fR) followed by short-term increases in VT and short-term decreases in fR. After brief hypoxia (< 1 min), recovery of the breathing pattern is again dynamic, where both VT and fR decrease immediately, but where VT remains above, and fR drops below, baseline. These acute changes are followed by a short-term progressive decrease in VT and increase in fR to baseline. We have identified a potential neural mechanism that depends on the integrity of the ventrolateral (vl) pens. Our studies show that: (a) blockade of activity in the vl pens prevents the short-term decrease in fR after hypoxia (b) stimulation of the vl pens decreases fR, and (c) vl pontine expiratory neurons are activated after hypoxia. These neurons may not be acting through alpha(2)-adrenergic receptors, but their effect does depend on NMDA-type receptor function. We conclude that the vl pens is a critical element in the pontomedullary network that generates and modulates the fR response to acute hypoxia. (C) 2000 Elsevier Science B.V. All rights reserved.