Visualising homeostatic and hedonistic appetite in rats using functional MRI.

英国面临的最大健康问题是肥胖(过度储存脂肪)的流行程度不断上升。我们生活在一个能源丰富的社会，食物通常很便宜，很容易买到，而且我们的生活方式非常久坐不动。因此，我们调节体重的自然能力正在被削弱。肥胖甚至中等超重的人患糖尿病、血管疾病和癌症的几率大大增加：这使得肥胖相关疾病的治疗成为美国国家医疗服务体系(National Health Service)和世界各地类似机构的巨大负担。许多器官，包括脂肪组织、肝脏和胰腺，相互作用，调节我们的体重和我们身体正常运作所需的燃料的供应。然而，协调这一规定的是大脑。因此，我们需要了解大脑如何检测并对所有不同的信息源做出反应，这些信息源最终决定了我们吃了多少食物，以及我们储存了多少脂肪。由于大脑的复杂性，我们对这个器官是如何发挥作用的了解仍然有限，这并不令人惊讶。大脑有复杂的回路，试图平衡我们的食物摄入量和我们的能量需求。不幸的是，在人类中，食欲更多地受到其他因素的控制，而不是生理需求，比如一天中的几点，我们是否喜欢或不喜欢可用的食物，或者我们是否正在与其他人一起吃饭。控制饮食的最大问题之一是它是一种愉快和社交的体验。因此，如果我们想减肥，我们倾向于选择甜食或油腻食物/最糟糕的食物/而且即使我们吃饱了，我们也倾向于吃东西。我们将开发尖端技术来成像大脑对一些影响食欲的不同刺激的反应。因此，使用一台功能强大的磁共振成像(MRI)机器，类似于日常临床诊断中使用的机器，我们将确定大鼠大脑的哪个部分对于检测和响应这些信号是重要的。我们将测试一些能增加食欲的刺激，以评估大脑不同部分是如何相互作用的。当老鼠在整个成像过程中被麻醉时，刺激物将人为地模仿饥饿和进食的快乐。我们将利用这些信息来了解正常的大脑功能，这可能与肥胖的发展有何不同，以及治疗可能如何能够有所帮助。这一知识将使学者、卫生专业人员和制药业受益，使他们能够改善护理，并开发针对肥胖和厌食症等各种问题的药物。

The biggest health issue facing the UK is the increasing prevalence of obesity (excess storage of fat). We live in a society where energy-rich food is generally cheap and easily available, and where we have very sedentary life styles. Therefore, our natural ability to regulate our body weight is being undermined. Obese and even moderately-overweight individuals have greatly increased chances of developing diabetes, vascular diseases and cancer: making the treatment of obesity-related diseases an enormous burden on the National Health Service and similar agencies around the world. Many organs, including fat tissue, the liver and the pancreas, interact to regulate both our body weight and the availability of the fuels that we need for our bodies to function normally. However, it is the brain that co-ordinates this regulation. Thus, we need to understand how the brain detects and responds to all the different sources of information that ultimately determine how much we eat and how much body fat that we store. It is not surprising that, due to the complexity of the brain, we still have only a limited understanding of how this organ carries out the function. The brain has complex circuits that act to try and balance our food intake to our energy needs. Unfortunately, in humans appetite is controlled less by physiological requirements and more by other factors such as what time of the day it is, if we like or dislike the food that is available or if we are eating with other people. One of the biggest problems with controlling our eating is that it is a pleasurable and sociable experience. Thus, we tend to choose sweet or fatty foods / the worst kind if we wish to reduce our weight / and we tend to eat even if when we are replete. We will develop cutting-edge technology to image the brain's response to a number of different stimuli that affect appetite. Thus, using a powerful magnetic resonance imaging (MRI) machine, similar to that used in everyday clinical diagnosis, we will determine which part of a rat's brain is important for detecting and responding to these signals. We will test a number of stimuli that increase appetite in order to assess how different parts of the brain interact. As the rat is anaesthetised throughout the imaging, the stimuli will artificially mimic the feelings of hunger and the pleasure of eating. We will use this information to understand normal brain functioning, how this may differ with the development of obesity and how treatments may be able to help. This knowledge will benefit academics, health professionals and the pharmaceutical industry, enabling them to improve care and to develop drugs for problems as diverse as obesity and anorexia.