Paez X, Stanley B G, Leibowitz S F
Rockefeller University, New York, NY 10021.
Brain Res. 1993 Mar 19;606(1):167-70. doi: 10.1016/0006-8993(93)91586-h.
It has been proposed that norepinephrine (NE) in the paraventricular nucleus (PVN) acts to stimulate carbohydrate feeding specifically at the start of the active (dark) cycle in rats. This study used microdialysis to examine the relationship between endogenous levels of NE in the PVN at dark onset and the amount of food consumed at this time. The results indicated that: (1) in satiated rats on a lab chow diet, NE levels in the PVN, as opposed to sites anterior or lateral to this nucleus, were significantly higher during large meals around dark onset then they were during small meals or during intervals that preceded the large meals, and (2) in food-deprived animals given a pure carbohydrate diet at dark onset, PVN levels of NE just before the initiation of the meal were significantly higher in animals that consumed a relatively large carbohydrate meal (> 2.0 g) during the first dark hour, and they were significantly correlated across animals with the size of their carbohydrate meal. These findings are consistent with other evidence linking endogenous PVN NE to food intake at the beginning of the natural feeding cycle.
有人提出，室旁核（PVN）中的去甲肾上腺素（NE）在大鼠活动（黑暗）周期开始时专门刺激碳水化合物摄入。本研究使用微透析来检查黑暗开始时PVN中内源性NE水平与此时食物摄入量之间的关系。结果表明：（1）在食用实验室普通饲料的饱腹大鼠中，与该核前方或外侧的部位相比，黑暗开始时大餐期间PVN中的NE水平显著高于小餐期间或大餐之前的间隔期，并且（2）在黑暗开始时给予纯碳水化合物饮食的饥饿动物中，在第一个黑暗小时内摄入相对大量碳水化合物餐（>2.0克）的动物在进餐开始前PVN中的NE水平显著更高，并且在不同动物中它们与碳水化合物餐的大小显著相关。这些发现与将内源性PVN NE与自然进食周期开始时的食物摄入联系起来的其他证据一致。
