Most people realize there is a brain gut connection. Nervous tension can aggravate irritable bowel syndrome and common dyspepsia, or stomach upset.

 

　　If the brain can upset the gut, can the gut upset the brain?

 

　　Scientists studying depression in rats think that it can.

 

　　About twenty million Americans are diagnosed with depression each year, and medical specialists believe about ten percent of the population is affected by the disease. Antidepressants are popular, but they only work for thirty five to forty five percent of patients. So, new and innovative ways to deal with the disease are being explored.

 

　　Depressed people often have gut problems, but many assume this is because hormones are released because of the depression. To determine if that is always the case, researchers tested rats to see which came first, the depression, or the gut upset.

 

　　A group of ten day old male rats were given a mild stomach irritant for six days. Others received no treatment. They were then tested at eight to ten weeks of age with water swimming challenges, and mazes. Scientists measured their responses and measured levels of stress hormones.

 

　　They found that the rats receiving the stomach irritation weeks before were more depressed than the untreated rats. Even when researchers prevented the irritant from sending pain signal to the brain, the depression occurred.

 

　　Rats are not humans, and depression is often inherited, but this research gives scientist a new avenue to follow in depression treatment. The vagus nerve connects the gut to the brain. Stimulating the nerve has been used to treat depression, epilepsy, and help memory in humans and animals. That connection may hold the secret to new treatment regimes and prevention of the disease.

 

　　大脑和内脏之间有联系吗？

 

　　很多人认为大脑和内脏之间有联系。神经紧张可以加剧肠易激综合征和常见的消化不良，或称作是肠胃不适。

 

　　如果大脑可以使内脏感觉不适，那内脏可以反过来影响大脑吗？

 

　　研究老鼠抑郁症的科学家认为，这是可以的。

 

　　每年，大概有两千万美国人被诊断为患有抑郁症，医学专家相信有大约十分之一的人会受抑郁症的影响。抗抑郁药一直畅销，但它只对35%到45%的抑郁症患者有效。所以，治疗抑郁症的新型疗法正在探究中。

 

　　抑郁的人经常会有内脏疾病，但是很多人认为这是因为抑郁症导致的荷尔蒙分泌。为了检验这种说法是否准确，研究者对老鼠进行了测验，来验证到底是抑郁症诱发内脏不适，还是内脏不适导致抑郁症。

 

　　一组10天大的雄性老鼠连续六天接受轻度的肠胃刺激。其余的则不接受任何刺激。之后他们在8到10周大时接受游泳和迷宫测试。科学家对它们的反应和压力荷尔蒙的分泌情况进行了测量。

 

　　科学家们发现，之前几周接受肠胃刺激的老鼠比没有接受刺激的老鼠要更抑郁。即使当研究者停止刺激，不再让疼痛信息传输到大脑中，抑郁症状仍然会发生。

 

　　老鼠与人类不同，抑郁症通常是遗传的。但这项研究为科学家在抑郁症治疗上开辟了一条新的路子。迷走神经连接着内脏和大脑。刺激迷走神经已被用来治疗人类和动物的抑郁症、癫痫病和帮助恢复记忆了。二者之间的这种联系可能就孕育着治疗和预防该疾病的新方案。