Gustatory Processing of Free Fatty Acids

游离脂肪酸的味觉加工

• 批准号: 7330955
• 负责人: Jennifer Stratford
• 金额: $ 3万
• 依托单位: FLORIDA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7330955
• 关键词: Affect; Animals; Artificial Saliva; Attention; Behavioral; Bilateral; Brain; Cells; Characteristics; Code; Condition; Consumption; Cyclophosphamide; Data; Denervation; Detection; Development; Dietary Fats; Discrimination; Enhancers; Environment; Fatty Acids; Fatty acid glycerol esters; Flavoring; Food; Glossopharyngeal nerve structure; Growth and Development function; Human; Impairment; Life; Linoleic Acids; Lipase; Methods; Nerve; Nonesterified Fatty Acids; Obesity; Organ; Perception; Peripheral; Process; Protocols documentation; Receptor Cell; Research; Role; Saline; Saliva; Salivary; Salivary Glands; Savory; Sensory; Smell Perception; Sodium; Sodium Glutamate; Stimulus; Sublingual Gland; Sucrose; System; Taste Perception; Testing; Texture; Thinking; Unsaturated Fats; Water; chorda tympani; design; food flavor; hedonic; insight; neuroregulation; relating to nervous system; research study; response; saliva secretion

DESCRIPTION (provided by applicant): Fat is crucial for life as it promotes the growth and development of organs, including the brain. However, over consumption of fats can result in the development of obesity. In this regard, most animals (including humans) prefer savory foods that, not coincidental; have a high fat content. Thus, the taste of fat may enhance the favor of foods. Surprisingly, little research has investigated the taste of fat. Moreover, most research on fat taste has focused on behavioral responses to free fatty acids (FFAs), the building blocks of fats, rather than on neural coding of FFAs. The gustatory chorda tympani nerve (CT) has been implicated in FFA detection, as bilateral transection of the CT (CTX) significantly impairs the discrimination of linoleic acid (LA), a polvunsaturated free fatty acid and main component of some kinds of dietary fat (Stratford et al., 2006). Yet, the CT is unresponsive to lingual application of LA. Thus, a paradox exists and the exact role of the CT in LA taste discrimination remains unknown. This is particularly pertinent because an understanding of the mechanisms involved in fatty acid perception can provide insight into the development of obesity. The following experiments are designed to determine the role of the CT in LA gustatory responses using parallel behavioral and electrophvsiological methods. Because CTX disrupts:neural control of salivary secretion, Specific Aim 1 will determine the contribution of the salivary glands and salivary sodium concentration specifically to fat taste. Moreover, because fat is traditionally considered an enhancer for other tastes, Specific Aim 1 will also test the hypothesis that the addition of LA will modulate CT electrophysiological activity to other taste stimuli. In fact, LA may require a background of saliva (dilute saline) to activate taste cells (i.e., taste cells are incapable of responding to LA unless there is some low level of sodium in the environment). This would explain, in part, the discrepancy between my behavioral data (in which saliva is present) and CT electrophysiological data (in which salivary sodium is rinsed off during water rinses). Changes in CT responses to taste stimuli when LA is added would suggest that LA modulates CT responses to other taste stimuli. Finally, CTX does not abolish LA detection, suggesting that other gustatory nerves may also be involved. Specific Aim 2 will determine the role of peripheral gustatory nerves in LA taste using a conditioned taste aversion protocol with gustatory nerve transections. Impairment of LA taste discrimination following a specific gustatory nerve transection will implicate that gustatory nerve in LA taste detection. Thus, these data provide insight into the role of fat taste in the development of obesity.

描述（由申请人提供）：脂肪对生命至关重要，因为它促进器官（包括大脑）的生长和发育。然而，过多摄入脂肪会导致肥胖。在这方面，大多数动物（包括人类）都喜欢咸味食物，这并非巧合；脂肪含量高。因此，脂肪的味道可能会增强食物的好感。令人惊讶的是，很少有研究调查脂肪的味道。此外，大多数关于脂肪味道的研究都集中在对游离脂肪酸 (FFA)（脂肪的组成部分）的行为反应，而不是 FFA 的神经编码。味觉鼓室神经 (CT) 与 FFA 检测有关，因为 CT (CTX) 的双侧横断会显着损害亚油酸 (LA) 的辨别力，亚油酸 (LA) 是一种多不饱和游离脂肪酸，是某些膳食脂肪的主要成分 (Stratford et al., 2006)。然而，CT 对 LA 的舌侧应用没有反应。因此，存在一个悖论，并且 CT 在 LA 味觉辨别中的确切作用仍然未知。这是特别相关的，因为了解脂肪酸感知机制可以深入了解肥胖的发展。以下实验旨在使用并行行为和电生理学方法确定 CT 在 LA 味觉反应中的作用。由于 CTX 会破坏：唾液分泌的神经控制，具体目标 1 将确定唾液腺和唾液钠浓度对脂肪味道的具体影响。此外，由于脂肪传统上被认为是其他味觉的增强剂，因此特定目标 1 还将检验添加 LA 会调节 CT 电生理活动对其他味觉刺激的假设。事实上，LA 可能需要唾液（稀盐水）作为背景来激活味觉细胞（即味觉细胞无法对 LA 做出反应，除非环境中钠含量较低）。这可以部分解释我的行为数据（其中存在唾液）和 CT 电生理数据（其中唾液钠在水冲洗过程中被冲洗掉）之间的差异。添加 LA 时 CT 对味觉刺激的反应发生变化表明 LA 调节 CT 对其他味觉刺激的反应。最后，CTX 并没有废除 LA 检测，这表明其他味觉神经也可能参与其中。具体目标 2 将使用味觉神经横断的条件性味觉厌恶方案来确定外周味觉神经在 LA 味觉中的作用。特定味觉神经横断后 LA 味觉辨别力受损将暗示味觉神经参与 LA 味觉检测。因此，这些数据让我们深入了解脂肪味道在肥胖发展中的作用。