PET imaging of human brain a2-adrenoceptors and noradrenaline release: biomarkers for brain diseases; Focus depression

抑郁症是一种极度虚弱的疾病，对医疗服务和整个国家都有重大影响，据估计，每年的经济负担约为120亿美元。抑郁症是由正常大脑化学物质和过程的失衡引起的。今天可用的强大技术允许研究活人正常和不正常大脑中的大脑化学物质和过程。这些技术依赖于特殊设计的放射性化学物质的可用性，这些化学物质提供了一种可视化大脑中正在发生的事情的方法。这些放射性化学物质只能用于研究这些大脑化学物质和过程中的一小部分。在有它们的地方，它们促进了我们对大脑疾病的理解和治疗。去甲肾上腺素是一种在大脑中发现的信号化学物质，是我们目前无法使用上述技术研究的许多化学物质和过程之一。在使用动物和人体组织进行的研究中，这种化学物质及其参与的过程与抑郁症和许多其他使人衰弱的脑部疾病有关。使用这些信息来源的困难在于，它们依赖于我们在理解这些疾病如何在人类身上进展时所做的假设。例如，我们不是实验动物，尽管有许多相似之处使我们对疾病及其治疗的理解取得了很大进展，但在人类身上确认是非常重要的。使用死后的人体组织只能告诉我们发生了什么，而不是如何或何时发生的。因此，开发其中一种放射性化学物质，使我们能够研究正常人和抑郁症患者活体人脑中去甲肾上腺素及其相关过程，对于我们正确理解这种疾病至关重要。这反过来将使我们能够更好地诊断抑郁症，并为患者带来更好的预后。它还将使我们能够改进我们已经拥有的治疗方法，并开发新的更好的治疗方法。

Depression is an extremely debilitating disease that has a major impact on the health services and the nation as a whole, which is estimated financially to be around 12billion a year. Depression is caused by imbalances of normal brain chemicals and process. Powerful techniques available today allow the study of brain chemicals and processes in normal and abnormal brains in living people. These techniques relay on the availability of specially designed radioactive chemicals that provide a means to visualise what is happening in the brain. These radioactive chemicals are only available to study a small number of these brain chemicals and processes. Where they are available, they have been responsible for major increases in our understanding and treatment of brain diseases.Noradrenaline, a signalling chemical found throughout the brain is one of the many chemicals and process that we are currently unable to study using the techniques mentioned. This chemical and the processes it is involved in have been implicated in depression and many other debilitating brain diseases, in studies using animals and post mortem human tissue. The difficulties in using these sources of information are that they rely on assumptions being made in our understanding of how these diseases progress in humans. For example, we are not laboratory animals and while there are many similarities that have enabled great advances in our understanding of disease and their treatment confirmation in humans is very important. The use of post mortem human tissue only tells us what has happened and not how or when. Therefore, the development of one of these radioactive chemicals to enable the study of noradrenaline and its related processes in the living human brain of normal people and those suffering depression is critical to our proper understanding of this disease. This in turn will allow us to better diagnose depression and lead to a much better prognosis for the sufferer. It would also permit us to refine the treatments that we already have and to develop new and better ones.