Bernardis L L, Border J R
J Neurosci Res. 1975;1(5-6):485-93. doi: 10.1002/jnr.490010515.
Weanling male rats received electrolytic lesions in the ventromedial (VMN) and dorsomedial (MDN) hypothalamic nuclei, respectively. A third group served as sham-operated controls (CON). After the two hypothalamic syndromes had been well established, the animals were subjected to (1) a glucose preference test assessing the choice between a 10% w/v and a 35% w/v d-glucose solution, and (2) a test examining the anorexigenic effect of intraperitoneally injected glucose. Weanling rats with VMN lesions, like their mature counterparts, consistently preferred the stronger over the weaker glucose solution throughout the experiment (16 days). Weanling DMN rats, on the other hand, showed a bimodal response, initially like that of the CON rat, toward the end of the experiment, like that of the VMN rats. The weanling CON animals behaved differently from their mature counterparts, inasmuch as their preference for the dilute solution became evident only toward the latter part of the test. An analysis of the calorie intake shows that calories from glucose are similar in all three groups of rats, that the pattern and magnitude of caloric intake in DMN and CON rats are almost identical, and that the total caloric intake (from chow plus glucose) is reduced in the DMN rats because the calorie component from chow is profoundly reduced. In response to intraperitoneally injected glucose, VMN rats show a longer depression of food intake than has been reported for mature VMN rats. The CON and DMN rats recovered quicker and reached preinjection levels of food intake sooner than the VMN rats. The data indicate that in the weanling VMN rat, as in its mature counterpart, the VMN are involved in long-term feeding behavior and do respond to the metabolic signal arising from administered glucose. Nevertheless, the principle factor in their preference seems to be taste rather than solely a metabolic signal. The data show that the DMN are less involved in this sensing and integrating mechanism. In essence, the DMN rat functions quite normally, but its control system is set at a subnormal level.
断乳期雄性大鼠分别在腹内侧（VMN）和背内侧（MDN）下丘脑核接受电解损伤。第三组作为假手术对照组（CON）。在两种下丘脑综合征充分形成后，对动物进行以下实验：（1）葡萄糖偏好试验，评估动物在10% w/v和35% w/v d -葡萄糖溶液之间的选择；（2）一项检测腹腔注射葡萄糖的厌食效应的试验。在整个实验过程（16天）中，VMN损伤的断乳期大鼠与其成年对应物一样，始终偏好浓度较高的葡萄糖溶液而非较弱的葡萄糖溶液。另一方面，断乳期MDN大鼠表现出双峰反应，实验初期与CON组大鼠相似，而在实验末期则与VMN组大鼠相似。断乳期CON组动物的行为与其成年对应物不同，因为它们对稀释溶液的偏好仅在试验后期才明显。对卡路里摄入量的分析表明，三组大鼠中来自葡萄糖的卡路里相似，MDN组和CON组大鼠的卡路里摄入模式和量几乎相同，并且MDN组大鼠的总卡路里摄入量（来自食物加葡萄糖）减少，因为来自食物的卡路里成分大幅减少。腹腔注射葡萄糖后，VMN组大鼠的食物摄入量抑制时间比成年VMN组大鼠报道的更长。CON组和MDN组大鼠比VMN组大鼠恢复更快，且更快达到注射前的食物摄入水平。数据表明，断乳期VMN组大鼠与其成年对应物一样，VMN参与长期摄食行为，并且确实对注射葡萄糖产生的代谢信号有反应。然而，它们偏好的主要因素似乎是味道，而不仅仅是代谢信号。数据表明，MDN较少参与这种感知和整合机制。本质上，MDN组大鼠功能相当正常，但其控制系统设定在低于正常的水平。
