Neurodynamics of feeding behavior

我对了解动机状态的神经生理学机制很感兴趣。在这项拟议的研究中，我们将研究将老鼠的进食行为从寻找常规食物重新引导到高度可口的食物(甜蔗糖溶液)的神经元动力学。寻找蔗糖的大鼠减少了食物的摄入量，同时显著增加了蔗糖的摄入量。人们普遍认为，食欲是由下丘脑调节的。然而，喂食的享乐方面取决于大脑奖励系统的活动。前额叶皮质(PFC)是奖赏系统的重要组成部分。PFC投射到下丘脑的外侧，在蔗糖觅食的大鼠中被激活，但在觅食的大鼠中不被激活。相反，接受黄体生成素输入的背内侧下丘脑(DMH)在觅食的动物中被激活，但不是在寻找蔗糖的动物中。我们假设，在从常规的食物导向行为向可口的食物导向行为转变过程中，下丘脑内的激活动力学依赖于起源于PFC的信号。这些实验将研究(A)寻找食物和蔗糖的大鼠PFC、Lh和DMH的实时神经元活动的动态；(B)PFC和下丘脑之间联系的神经形态和神经化学；以及(C)PFC在寻找食物和蔗糖的大鼠下丘脑激活中的作用。目前的建议旨在研究参与食物动机行为的神经元分布网络的神经元底物和动态功能。为了实现这一目标，我们将使用分子生物学方法(原位杂交和免疫组织化学)、体内电生理技术和形态学方法(光学和电子显微镜)。拟议的研究将提供一个难得的培训机会。学生将使用多种最先进的研究技术来研究神经网络的基本组织和功能动力学。他们的培训将在研究中心(CRIUCPQ)的出色环境中进行，并有多个当地和国际合作。

I am interested in understanding the neurophysiological mechanisms of motivational states. In the proposed study we will investigate the neuronal dynamics that re-direct rats' feeding behavior from seeking of regular chow to highly palatable food (sweet sucrose solution). Sucrose-seeking rats decrease their intake of chow while dramatically escalating intake of sucrose. It is commonly accepted that appetite is regulated by the hypothalamus. However, hedonic aspect of feeding depends on the activity of the brain reward system. The prefrontal cortex (PFC) is an important component of the reward system. The PFC projects to the lateral hypothalamus (LH), which is activated in the sucrose- but not chow-seeking rats. Conversely, the dorsomedial hypothalamus (DMH), which receives the input from the LH, is activated in the chow- but not sucrose-seeking animals. We hypothesize that dynamics in activation within the hypothalamus, which occur during transition from the regular- to palatable-food-oriented behaviour, depend on the signals originated in the PFC. The proposed experiments will investigate (a) the dynamics of real-time neuronal activity in the PFC, LH, and DMH in the chow- and sucrose-seeking rats; (b) the neuromorphology and neurochemistry of the connections between the PFC and the hypothalamus, and (c) the role of the PFC in the hypothalamic activation in the chow- and sucrose-seeking rats. The current proposal is designed to investigate the neuronal substrate and the dynamic functions of the neuronal distributed network involved in the food-motivated behavior. To achieve this objective, we will use the methods of molecular biology (in situ hybridization and immunohistochemistry), in vivo electrophysiological techniques, and morphological methods (light and electron microscopy). The proposed study will provide an exceptional opportunity for training. The students will investigate the basic organization and functional dynamics of the neuronal network using a multitude of state-of-the-art research techniques. Their training will occur in the outstanding environment of the research center (CRIUCPQ) with multiple local and international collaborations.