Centro de Investigaciones Biomédicas, Universidad Veracruzana, A.P. # 114, Xalapa, Veracruz, México.
Eur J Neurosci. 2012 May;35(9):1458-65. doi: 10.1111/j.1460-9568.2012.08051.x. Epub 2012 Apr 3.
Rabbit pups represent a natural model of food anticipatory activity (FAA). FAA is the behavioral output of a putative food entrainable oscillator (FEO). It had been suggested that the FEO is comprised of a distributed system of clocks that work in concert in response to gastrointestinal input by food. Scheduled food intake synchronizes several nuclei in the brain, and the hypothalamus has received particular attention. On the contrary, brainstem nuclei, despite being among the brain structures to first receive food cues, have been scarcely studied. Here we analysed by immunohistochemistry possible oscillation of FOS and PER1 proteins through a complete 24-h cycle in the dorsal vagal complex (DVC) and parabrachial nucleus (PBN) of 7-8-day-old rabbit pups scheduled to nurse during the night (02:00 h) or day (10:00 h), and also in fasted subjects to explore the possible persistence of oscillations. We found a clear induction of FOS that peaks 1.5 h after nursing in all nuclei studied. PER1 was only synchronized in the PBN, reaching highest values 12 h after nursing. Only PER1 oscillations persisted, with a shift, in fasted subjects. We conclude that the DVC nuclei are probably more related to the transmission of food cues to other brain regions, but that the PBN participates in the integration of information essential for FAA. Our results support previous findings suggesting that the DVC nuclei, but not PBN, are not essential for FAA. We suggest that PBN is a key component of the proposed distributed system of clocks involved in FAA.
兔仔代表了一种自然的食物预期活动（FAA）模型。FAA 是一种假定的食物可诱导振荡器（FEO）的行为输出。有人认为，FEO 由一个分布式时钟系统组成，该系统通过食物的胃肠道输入协同工作。定时进食会使大脑中的几个核同步，而下丘脑受到了特别关注。相反，脑干核尽管是首先接收食物线索的大脑结构之一，但研究甚少。在这里，我们通过免疫组织化学分析了在计划夜间（02:00 h）或白天（10:00 h）哺乳的 7-8 天大的兔仔的背侧迷走复合体（DVC）和臂旁核（PBN）中，FOS 和 PER1 蛋白在完整的 24 小时周期中可能发生的振荡，也在禁食的动物中进行了研究，以探索可能存在的振荡持续。我们发现，在所有研究的核中，FOS 的诱导非常明显，在哺乳后 1.5 小时达到峰值。PER1 仅在 PBN 中同步，在哺乳后 12 小时达到最高值。只有 PER1 振荡持续存在，在禁食的动物中存在偏移。我们得出结论，DVC 核可能与将食物线索传递给其他大脑区域有关，但 PBN 参与了 FAA 所必需的信息整合。我们的结果支持了先前的发现，表明 DVC 核而不是 PBN 对于 FAA 并非必需。我们建议 PBN 是参与 FAA 的提议的分布式时钟系统的关键组成部分。
