Mullen B J, Martin R J
Department of Foods and Nutrition, University of Georgia, Athens 30602.
Am J Physiol. 1992 Sep;263(3 Pt 2):R559-63. doi: 10.1152/ajpregu.1992.263.3.R559.
Rats consuming a diet of 34% tallow select more protein and less carbohydrate than rats fed either 5% corn oil or tallow or 34% corn oil (25). To examine potential mechanism(s) of this phenomenon, we fed rats diets containing either tallow or corn oil at levels of 5 or 34% for 2 days. Sera were analyzed, and rats fed 34% tallow had higher serum insulin compared with those fed 34% corn oil. In a second experiment, rats were fed either 34% corn oil or tallow for 2 days. Brain tissues were analyzed, and rats fed 34% tallow had elevated serotonin in the raphe area compared with those fed 34% corn oil. In a third experiment, rats were fed either 34% corn oil or tallow for 2 days and then given dl-fenfluramine before diet selection. Fenfluramine depressed food intake to a greater degree in rats fed 34% tallow compared with those fed corn oil. These findings suggest that the diet selection behavior observed in tallow-fed rats may be mediated by a central serotonin system.
与喂食5%玉米油或牛脂或34%玉米油的大鼠相比，食用含34%牛脂饮食的大鼠会选择更多的蛋白质和更少的碳水化合物(25)。为了研究这一现象的潜在机制，我们给大鼠喂食含5%或34%牛脂或玉米油的饮食，持续2天。对血清进行分析后发现，与喂食34%玉米油的大鼠相比，喂食34%牛脂的大鼠血清胰岛素水平更高。在第二个实验中，给大鼠喂食34%玉米油或牛脂，持续2天。对脑组织进行分析后发现，与喂食34%玉米油的大鼠相比，喂食34%牛脂的大鼠中缝区域的血清素水平升高。在第三个实验中，给大鼠喂食34%玉米油或牛脂，持续2天，然后在进行饮食选择前给予dl-芬氟拉明。与喂食玉米油的大鼠相比，芬氟拉明对喂食34%牛脂的大鼠的食物摄入量抑制作用更大。这些发现表明，在喂食牛脂的大鼠中观察到的饮食选择行为可能由中枢血清素系统介导。
