Neurocircuitry of a novel gastrointestinal-circulatory reflex

新型胃肠循环反射的神经回路

• 批准号: nhmrc : 350207
• 负责人: A/Pr Anthony Verberne
• 金额: $ 34.38万
• 依托单位: The University of Melbourne
• 依托单位国家: 澳大利亚
• 项目类别: NHMRC Project Grants
• 财政年份: 2005
• 资助国家: 澳大利亚
• 起止时间: 2005-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/neurocircuitry-novel-gastrointestinal-circulatory-reflex/99450
• 关键词: Neurocircuitry; novel; gastrointestinal; circulatory; reflex

The gastrointestinal tract receives about one third of the blood pumped around the body by the heart. This implies that the gut circulation plays a major role in blood pressure control. Gut blood flow changes according to the demands imposed by altered behavioural activity. Engagement in physical exercise results in increased blood flow to the working muscles of the limbs and diversion away from the gut. Alternatively, food consumption promotes an increase in blood flow to the gut to aid digestion. While this is a normal bodily process, there are also adverse implications of the re-distribution of blood flow: in the elderly compensation for these changes is often impaired and can result in low blood pressure and fainting. In addition, the incidence of angina-related heart pain is greater after food consumption and this may be associated with re-distribution of blood flow to the gut. Cholecystokinin (CCK), a hormone which is released from special cells that line the intestine, plays a role in the control of blood flow to the gut. We have developed the hypothesis that CCK acts on nerves which send a signal to the brain which, in turn, acting through other nerves, produces an increase in the flow of blood to the gut. This project is designed to study the nerve pathways in the brain which control this novel mechanism. We will record the activity of specific brain cells and nerves which are involved in the control of the blood supply to the gut. We will also examine which chemicals the brain cells and nerves use for communication with each other and so build up a model of the brain areas which are involved in gut blood flow control. This project will shed new light on the mechanisms of gut blood flow control and identify the associated brain pathways. The information will be of importance in the treatment of diseases of the circulation and food consumption-related cardiovascular changes in the elderly and obese as well as in sufferers of angina.

胃肠道接收心脏泵送至全身的大约三分之一的血液。这意味着肠道循环在血压控制中发挥着重要作用。肠道血流量根据行为活动改变的需求而变化。参加体育锻炼会增加流向四肢工作肌肉的血液，并将血液从肠道转移出去。另外，食物消耗会促进肠道血流量增加，以帮助消化。虽然这是正常的身体过程，但血流的重新分配也会产生不利影响：在老年人中，对这些变化的代偿通常会受到损害，并可能导致低血压和昏厥。此外，进食后心绞痛相关的心痛发生率更高，这可能与肠道血流的重新分配有关。胆囊收缩素 (CCK) 是一种从肠道内的特殊细胞释放的激素，在控制肠道血流中发挥着重要作用。我们提出了这样的假设：CCK 作用于向大脑发送信号的神经，而大脑又通过其他神经起作用，导致流向肠道的血液增加。该项目旨在研究大脑中控制这种新机制的神经通路。我们将记录参与控制肠道血液供应的特定脑细胞和神经的活动。我们还将检查脑细胞和神经使用哪些化学物质相互沟通，从而建立参与肠道血流控制的大脑区域的模型。该项目将为肠道血流控制机制提供新的线索，并确定相关的大脑通路。这些信息对于治疗老年人和肥胖者以及心绞痛患者的循环系统疾病和与食物消耗相关的心血管变化具有重要意义。