ATP -a mediator of central chemoreception in brain stem

没有机械辅助，靠意志力停止呼吸是不可能的。为什么?因为吸入的空气和血液中的二氧化碳含量是一种极其强大的呼吸驱动力？如果这些水平上升（就像在自我窒息或从塑料袋中重新呼吸时一样），我们的呼吸就会更加有力和迅速。长期以来，人们一直知道脑干的专门区域可以检测大脑中的二氧化碳，并将这些信息传递给控制呼吸的神经网络。尽管如此，二氧化碳探测（化学接收）的详细机制，以及化学感觉细胞本身仍然未知。我们最近取得了突破性进展，发现ATP在二氧化碳升高时从脑干的这些专门区域释放出来，是化学感觉反射的重要环节。现在我们将利用实验上更简单的脑干体外制剂来利用这一发现。我们将研究ATP释放的机制，因为这将使我们对化学接受的机制有一个基本的了解。因此，我们将制作ATP释放位置的详细地图。我们将看看ATP释放的特征，这可能会突出在二氧化碳升高时释放ATP的细胞类型。我们将识别化学感觉细胞内负责检测二氧化碳变化并最终导致ATP释放的离子通道。最后，我们将检查从分离细胞中释放的ATP对二氧化碳的反应，以便我们识别它们。

Without a mechanical aid, it is impossible to stop breathing by will power. Why? Because the levels of CO2 in inspired air and in blood are an extremely powerful drive to breathe ?if these levels go up (as they would during self-willed asphyxiation or re-breathing from a plastic bag) we breathe more powerfully and rapidly. Specialized areas of the brain stem have long been known to detect CO2 in brain and relay this information to the neural networks that control breathing. Despite this, the detailed mechanisms of CO2 detection (chemoreception), and indeed the chemosensory cells themselves remain unknown. We have recently made a breakthrough in discovering that ATP is released from these specialized areas of the brain stem during elevated CO2 and is an essential link in the chemosensory reflex. We shall now exploit this finding by using experimentally simpler in vitro preparations of the brain stem. We shall look at the mechanisms of ATP release, as these will lead us to a fundamental understanding of the mechanisms of chemoreception. Thus we shall produce detailed maps of the locations of ATP release. We shall look at the characteristics of ATP release, which may highlight the types of cells that release ATP during elevated CO2. We shall identify the ion channels within the chemosensory cells responsible for detecting changes in CO2 and ultimately causing the release of ATP. Finally we shall examine release from of ATP from isolated cells in response to CO2 to allow us to identify them.