RUI: Taste of Monosodium Glutamate and Sweet

RUI：味精的味道和甜味

• 批准号: 9982913
• 负责人: Eugene Delay
• 金额: $ 16.5万
• 依托单位: Regis University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2004-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9982913&HistoricalAwards=false
• 关键词: RUI; Taste; Monosodium; Glutamate; Sweet

Monosodium glutamate (MSG) is found in many high protein foods such as meat and fish and it is often added to food to enhance the taste of food. However, we do not understand how our taste receptors detect the taste of MSG. One way we can study these processes is to compare the behavioral responses of rats to MSG with their responses to other taste stimuli. Forexample, rats normally prefer the taste of MSG but if they experience gastric distress after ingesting MSG, these rats will avoid MSG and anything that tastes like MSG. This is called conditioned taste aversion (CTA). The proposed research is designed to test this hypothesis. We first need to determine whether the taste of MSG with amiloride mimics taste qualities of other sweet substances. There are at least two mechanisms that taste receptors use to detect sweet substances, one for natural sugars such as sucrose and another for artificial sweeteners such as saccharin. The first experiments will use CTA and behavioral discrimination procedures to determine if rats perceive the taste of MSG with amiloride as similar to sweet substances other than sucrose (natural sugars and artificial sweeteners). These experiments will help determine whether the taste of glutamate is similar to either natural sugars, artificial sweeteners, or to both. If the taste of MSG with amiloride is similar tosweet stimuli then these taste stimuli may be coded by cells in the same areas of the nervous system. To test this hypothesis, another experiment will use a cell marker method to identify cells in the brain stem (solitary nucleus) activated by MSG and those sweet stimuli that taste most likeglutamate in the first experiments. The degree to which the location of cells activated by these stimuli overlap with each other may indicate the degree to which the neurons involved in coding of these taste stimuli interact within the gustatory system of the brain stem The informationlearned from these experiments will help us understand why MSG increases the palatability of some foods and may be used to help people, such as the elderly or diabetics, who need dietary regulation.

谷氨酸钠（味精）存在于许多高蛋白食物中，如肉类和鱼类，它经常被添加到食物中以增强食物的味道。然而，我们不知道我们的味觉感受器如何检测味精的味道。我们研究这些过程的一种方法是将老鼠对味精的行为反应与它们对其他味觉刺激的反应进行比较。例如，老鼠通常喜欢味精的味道，但如果它们在摄入味精后感到胃部不适，这些老鼠将避免味精和任何尝起来像味精的东西。这就是所谓的条件性味觉厌恶（CTA）。拟议的研究旨在验证这一假设。我们首先需要确定味精与阿米洛利的味道是否模仿其他甜味物质的味道。味觉感受器至少有两种机制来检测甜味物质，一种是天然糖，如蔗糖，另一种是人工甜味剂，如糖精。第一个实验将使用CTA和行为辨别程序来确定大鼠是否认为味精与阿米洛利的味道与蔗糖（天然糖和人工甜味剂）以外的甜味物质相似。这些实验将有助于确定谷氨酸盐的味道是否与天然糖、人工甜味剂或两者相似。如果味精与阿米洛利的味道与甜味刺激相似，那么这些味觉刺激可能是由神经系统相同区域的细胞编码的。为了验证这一假设，另一个实验将使用细胞标记方法来识别脑干（孤核）中被味精激活的细胞，以及那些在第一个实验中尝起来最像谷氨酸的甜味刺激。由这些刺激激活的细胞的位置相互重叠的程度可能表明参与编码这些味觉刺激的神经元在脑干味觉系统中相互作用的程度。从这些实验中获得的信息将帮助我们理解为什么味精增加了某些食物的适口性，并可能用于帮助需要饮食调节的人，如老年人或糖尿病患者。