Angeles-Castellanos Manuel, Aguilar-Roblero Raul, Escobar Carolina
Departamento de Anatomía, Facultad de Medicina, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City DF 04510, Mexico.
Am J Physiol Regul Integr Comp Physiol. 2004 Jan;286(1):R158-65. doi: 10.1152/ajpregu.00216.2003. Epub 2003 Aug 21.
The present study aimed to identify the hypothalamic nuclei involved with food entrainment by using c-Fos-like immunoreactivity (c-Fos-IR) as a marker of functional activation. We studied rats entrained 3 wk to restricted feeding schedules (RF), their ad libitum (AL) controls, and the persistence of c-Fos-IR temporal patterns in entrained-fasted rats. In addition, we included 22-h fasting and 22-h fasting-refeeding groups as controls of fasting and refeeding acute effects. Diurnal patterns of c-Fos-IR were observed in the tuberomammilar nucleus (TM) and suprachiasmatic nucleus (SCN) in AL rats. In all nuclei, except the SCN and ventromedial nucleus (VMH), restricted feeding schedules imposed a temporal pattern of increased c-Fos-IR around mealtime. An increase in c-Fos-IR before and after meal time was observed in dorsomedial nucleus (DMH), lateral nucleus (LH), perifornical area (PeF), and TM, and a marked increase was observed in the paraventricular nucleus (PVN) after feeding. Food-entrained c-Fos-IR patterns persisted after 3 days in fasting in DMH, LH, and PeF. Present data suggest that FEO might not rely on a single nucleus and rather may be a distributed system constituted of interacting nuclei in which the PVN is mainly involved with the response to signals elicited by food ingestion and, therefore, with the entraining pathway. We can suggest that the PeF and TM may be involved with the arousal state during food anticipation and the DMH and LH with the time-keeping mechanism of FEO or its output.
本研究旨在通过使用c-Fos样免疫反应性（c-Fos-IR）作为功能激活的标志物来确定参与食物诱导的下丘脑核团。我们研究了被限制进食时间表（RF）3周的大鼠、它们的自由进食（AL）对照以及在禁食的定时进食大鼠中c-Fos-IR时间模式的持续性。此外，我们纳入了22小时禁食和22小时禁食-再喂养组作为禁食和再喂养急性效应的对照。在AL大鼠的乳头体核（TM）和视交叉上核（SCN）中观察到了c-Fos-IR的昼夜模式。在所有核团中，除了SCN和腹内侧核（VMH），限制进食时间表在进餐时间前后施加了c-Fos-IR增加的时间模式。在背内侧核（DMH）、外侧核（LH）、穹隆周区（PeF）和TM中观察到进餐时间前后c-Fos-IR增加，并且在进食后室旁核（PVN）中观察到显著增加。在DMH、LH和PeF中，禁食3天后食物诱导的c-Fos-IR模式持续存在。目前的数据表明，食物预期性进食（FEO）可能不依赖于单个核团，而可能是一个由相互作用的核团组成的分布式系统，其中PVN主要参与对食物摄入引发的信号的反应，因此也参与诱导途径。我们可以认为，PeF和TM可能参与食物预期期间的觉醒状态，而DMH和LH参与FEO的计时机制或其输出。
