Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa, Ver., Mexico.
Facultad de Medicina, Universidad Nacional Autónoma de México, CDMX, Mexico.
Sci Rep. 2021 Oct 7;11(1):19957. doi: 10.1038/s41598-021-99266-0.
The mechanisms underlying food anticipatory activity are still poorly understood. Here we explored the role of oxytocin (OT) and the protein c-Fos in the supraoptic nucleus (SON), medial (PVNm) and posterior (PVNp) regions of the paraventricular hypothalamic nucleus. Adult rats were assigned to one of four groups: scheduled restricted feeding (RF), ad libitum (AL), fasting after restricted feeding (RF-F), to explore the possible persistence of oscillations, or ad libitum fasted (AL-F). In the SON and in the PVNm, OT cells were c-Fos positive after food intake; in contrast, OT cells in the PVNp showed c-Fos activation in anticipation to food access, which persisted in RF-F subjects. We conclude that OT and non-OT cells of the SON and PVNm may play a role as recipients of the entraining signal provided by food intake, whereas those of the PVNp which contain motor preautonomic cells that project to peripheral organs, may be involved in the hormonal and metabolic anticipatory changes in preparation for food presentation and thus, may be part of a link between central and peripheral oscillators. In addition, due to their persistent activation they may participate in the neuronal network for the clock mechanism that leads to food entrainment.
食物预期活动的机制仍未被充分理解。在这里，我们探讨了催产素 (OT) 和 c-Fos 蛋白在视上核 (SON)、室旁核的内侧 (PVNm) 和后区 (PVNp) 中的作用。成年大鼠被分为四组之一：定时限制喂养 (RF)、自由喂养 (AL)、限制喂养后的禁食 (RF-F)，以探索可能存在的振荡持续时间，或自由喂养禁食 (AL-F)。在 SON 和 PVNm 中，摄食后 OT 细胞呈 c-Fos 阳性；相比之下，PVNp 中的 OT 细胞在食物摄入前表现出 c-Fos 激活，这种激活在 RF-F 组中持续存在。我们得出结论，SON 和 PVNm 的 OT 和非 OT 细胞可能作为食物摄入提供的调谐信号的接收者发挥作用，而含有投射到外周器官的自主运动前细胞的 PVNp 可能参与为食物呈现做准备的激素和代谢性预期变化，因此，可能是中央和外周振荡器之间联系的一部分。此外，由于它们的持续激活，它们可能参与导致食物同步的时钟机制的神经元网络。
