Eckel L A, Langhans W, Kahler A, Campfield L A, Smith F J, Geary N
E. W. Bourne Laboratory, New York Hospital-Cornell Medical Center, White Plains, New York 10605, USA.
Am J Physiol. 1998 Jul;275(1):R186-93. doi: 10.1152/ajpregu.1998.275.1.R186.
The mechanisms by which OB protein controls food intake and energy balance are unknown. Therefore, we investigated the effects of a novel modified human recombinant OB protein (Mod-OB) on spontaneous feeding patterns, body weight, running wheel activity, and ovarian cycling in female rats. Mod-OB or vehicle was injected (4 mg . kg-1 . day-1 sc) for 2 ovarian cycles (8 days) using a within-subjects design. Observations were continued for five ovarian cycles after injections; treatments were then reversed. Mod-OB reduced food intake approximately 20% from injection day 1 to postinjection day 2. Body weight was reduced from injection day 3 to postinjection day 15 (maximum decrease, 25 +/- 4 g, postinjection days 3 and 4). Food intake was reduced due to decreases in nocturnal meal size, which appeared to be superimposed on the normal pattern of spontaneous feeding (i.e., reductions in meal size at estrus). Mod-OB did not significantly affect diurnal food intake or meal patterns, failed to alter wheel running, and did not disrupt the rats' ovarian cycles. We conclude that chronically administered Mod-OB reduces food intake in female rats by selectively affecting the mechanisms controlling meal size.
OB蛋白控制食物摄入和能量平衡的机制尚不清楚。因此，我们研究了一种新型修饰的人重组OB蛋白（Mod-OB）对雌性大鼠自发进食模式、体重、转轮活动和卵巢周期的影响。采用自身对照设计，给予Mod-OB或赋形剂（4 mg·kg-1·天-1，皮下注射），持续2个卵巢周期（8天）。注射后继续观察5个卵巢周期；然后颠倒处理。从注射第1天到注射后第2天，Mod-OB使食物摄入量减少了约20%。从注射第3天到注射后第15天体重减轻（最大减少量为25±4 g，在注射后第3天和第4天）。食物摄入量减少是由于夜间进餐量减少，这似乎叠加在正常的自发进食模式上（即发情期进餐量减少）。Mod-OB对日间食物摄入量或进餐模式没有显著影响，未能改变转轮活动，也未扰乱大鼠的卵巢周期。我们得出结论，长期给予Mod-OB可通过选择性影响控制进餐量的机制来减少雌性大鼠的食物摄入量。
