Hogan S, Himms-Hagen J, Coscina D V
Physiol Behav. 1985 Aug;35(2):287-94. doi: 10.1016/0031-9384(85)90351-8.
Radiofrequency heat lesions were made in the medial hypothalamus of 12-week old male and female Holtzman rats. Two to three days later rats were offered a palatable cafeteria diet in addition to chow or were fed chow alone for the next 3-4 weeks. Male lesioned rats were only slightly hyperphagic on the chow diet and gained little extra weight. When fed the cafeteria diet, energy intake of male lesioned rats almost doubled in comparison with chow-fed lesioned rats and a very rapid extra weight gain occurred. Despite the marked hyperphagia, thermogenesis in brown adipose tissue was suppressed in the cafeteria-fed lesioned rats, as indicated by low mitochondrial guanosine diphosphate (GDP) binding. In female rats, lesions induced much greater hyperphagia and body weight gain than in male rats, particularly when they ate the cafeteria diet. Again, thermogenesis in brown adipose tissue was suppressed in the cafeteria-fed female lesioned rats. The proportion of energy derived from carbohydrate was not altered by the cafeteria diet in either male or female rats, whether lesioned or not, but there was an increase in the proportion of energy derived from fat at the expense of protein. No sex differences in food selection were observed. The accumulation of body fat was always greater in female lesioned rats than in male lesioned rats for similar food intakes. It is concluded that medial hypothalamic lesions prevent the normal occurrence of diet-induced thermogenesis in brown adipose tissue despite extreme overeating by the rats of a palatable cafeteria diet.
对12周龄的雄性和雌性霍尔兹曼大鼠的下丘脑内侧进行射频热损伤。两到三天后，除了普通食物外，给大鼠提供美味的自助饮食，或者在接下来的3 - 4周内只喂普通食物。雄性损伤大鼠在普通饮食时只是略有食欲亢进，体重增加很少。当喂食自助饮食时，与喂食普通食物的损伤大鼠相比，雄性损伤大鼠的能量摄入量几乎翻倍，体重迅速增加。尽管有明显的食欲亢进，但喂食自助饮食的损伤大鼠棕色脂肪组织中的产热受到抑制，线粒体鸟苷二磷酸（GDP）结合率低表明了这一点。在雌性大鼠中，损伤引起的食欲亢进和体重增加比雄性大鼠大得多，尤其是当它们吃自助饮食时。同样地，喂食自助饮食的雌性损伤大鼠棕色脂肪组织中的产热也受到抑制。无论是否损伤，雄性或雌性大鼠从碳水化合物中获取的能量比例都没有因自助饮食而改变，但从脂肪中获取的能量比例增加，以蛋白质为代价。未观察到食物选择上的性别差异。对于相似的食物摄入量，雌性损伤大鼠的体脂积累总是比雄性损伤大鼠多。得出的结论是，下丘脑内侧损伤会阻止棕色脂肪组织中饮食诱导的产热正常发生，尽管大鼠食用美味的自助饮食会极度暴饮暴食。
