Role of PBN Subnuclei in Oromotor Behaviors

PBN 亚核在口部运动行为中的作用

• 批准号: 0090641
• 负责人: Michael King
• 金额: $ 9.52万
• 依托单位: Stetson University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-15 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0090641&HistoricalAwards=false
• 关键词: Role; PBN; Subnuclei; Oromotor; Behaviors

Taste information travels from the mouth to the brain within nerves that terminate in a part of the medulla oblongata called the nucleus of the solitary tract (NST). The NST is interconnected with another part of the brainstem called the parabrachial nucleus (PBN). Both the PBN and NST act as processing and distribution centers for taste information. They send some taste information to higher brain centers so that the taste quality can be perceived. The PBN and NST also send outputs to motor centers in the brainstem that produce motor responses to the taste input. Within the PBN, there are two distinct regions that respond to taste input. One of these regions (CM/VL) responds best to salt on the anterior tongue while the other (EM/EL) responds best to bitter taste on the posterior tongue. Due to this difference in responses to taste input, it is hypothesized that the two PBN areas control different motor responses. Specifically, it is hypothesized that CM/VL controls ingestive behaviors (like mouth movements and tongue protrusions) while EM/EL controls aversive behaviors (like gapes). Undergraduate Biology and Psychology students and their faculty mentors, will address these hypotheses by stimulating discrete areas of the PBN while observing motor responses. This procedure will allow the construction of a functional map of the PBN. Specifically, CM/VL and EM/EL will be stimulated in separate groups of conscious rats using implanted electrode-cannula systems. First, these areas will be electrically stimulated while oral motor behaviors are videotaped. Following electrical stimulation, injection of glutamate (an excitatory neurotransmitter) through the cannula into the same location within the PBN will occur. The combination of electrical and chemical stimulation will allow accurate assessment of the specific neural elements responsible for the behavioral effects. The motor responses will be correlated with the histological localization of the stimulation sites. As mentioned, based on previous findings, it is hypothesized that stimulation of CM/VL will generate ingestive behaviors, while stimulation of EM/EL will evoke aversive responses.This study employs a straightforward strategy to define the effects of taste-responsive PBN regions on oral motor behaviors. The potential impact of the project on the understanding of central processing of taste input and the function of the PBN is substantial. Specifically, elucidation of a functional topography (map) within the PBN would significantly improve the understanding of the central mechanisms producing oral motor responses to taste input.

味觉信息通过神经从口腔传递到大脑，这些神经终止于延髓的一部分，称为孤束核（NST）。 NST与脑干的另一部分相互连接，称为臂旁核（PBN）。 PBN和NST都是味觉信息的处理和分配中心。 它们将一些味觉信息发送到更高的大脑中心，以便感知味觉质量。 PBN和NST还将输出发送到脑干中的运动中心，这些运动中心对味觉输入产生运动反应。在PBN内，有两个不同的区域对味觉输入做出反应。 其中一个区域（CM/VL）对前舌上的盐反应最好，而另一个区域（EM/EL）对后舌上的苦味反应最好。 由于对味觉输入的反应的这种差异，假设两个PBN区域控制不同的运动反应。 具体而言，假设CM/VL控制摄食行为（如嘴部运动和舌头伸出），而EM/EL控制厌恶行为（如张口）。 本科生物学和心理学的学生和他们的教师导师，将通过刺激PBN的离散区域，同时观察运动反应来解决这些假设。 该程序将允许构建PBN的功能图。 具体而言，CM/VL和EM/EL将使用植入的电极-套管系统在不同的清醒大鼠组中进行刺激。 首先，这些区域将被电刺激，而口腔运动行为被录像。 电刺激后，将通过套管将谷氨酸盐（一种兴奋性神经递质）注射到PBN内的相同位置。 电刺激和化学刺激的结合将允许准确评估负责行为效应的特定神经元素。 运动反应将与刺激部位的组织学定位相关。 如前所述，基于先前的研究结果，假设刺激CM/VL会引起摄食行为，而刺激EM/EL会引起厌恶反应。 该项目对理解味觉输入的中央处理和PBN的功能的潜在影响是巨大的。 具体而言，阐明PBN内的功能地形图（地图）将显着提高对味觉输入产生口腔运动反应的中枢机制的理解。