King B M, Smith R L
Am J Physiol. 1985 Nov;249(5 Pt 2):R522-6. doi: 10.1152/ajpregu.1985.249.5.R522.
Recent studies have found that the hyperphagia and obesity resulting from lesions of the ventromedial hypothalamus (VMH) are both reversed and prevented by complete adrenalectomy. Several previous experiments, however, reported little or no suppression of VMH weight gain in hypophysectomized (HYPOX) rats. This study directly compared the effects of hypophysectomy and adrenalectomy on hypothalamic obesity in adult female rats. Complete adrenalectomy (i.e, stress-induced plasma corticosterone less than 1.0 micrograms/dl) totally suppressed abnormal weight gain in the first 20 days after VMH lesions but did not affect intracranial self-stimulation. Hypophysectomy also resulted in suppression of weight gain, but the HYPOX-VMH rats nevertheless gained significantly more weight than HYPOX rats with sham lesions. However, the HYPOX-VMH animals had very low levels of plasma corticosterone and adrenocorticotropin (ACTH) (from residual pituitary tissue or of diencephalic origin), and incompletely adrenalectomized rats with similar low levels of plasma corticosterone gained an equal amount of weight after VMH lesions. It was concluded that adrenal glucocorticoid hormones play a largely permissive role in the VMH syndrome, with only very small levels required for the manifestation of obesity.
近期研究发现，腹内侧下丘脑（VMH）损伤所致的食欲亢进和肥胖，通过完全肾上腺切除术均可得到逆转和预防。然而，此前的一些实验报道称，垂体切除（HYPOX）大鼠的VMH体重增加几乎没有或完全没有受到抑制。本研究直接比较了垂体切除术和肾上腺切除术对成年雌性大鼠下丘脑性肥胖的影响。完全肾上腺切除术（即应激诱导的血浆皮质酮低于1.0微克/分升）在VMH损伤后的前20天完全抑制了异常体重增加，但不影响颅内自我刺激。垂体切除术也导致体重增加受到抑制，但垂体切除 - VMH大鼠的体重仍显著高于假损伤的垂体切除大鼠。然而，垂体切除 - VMH动物的血浆皮质酮和促肾上腺皮质激素（ACTH）水平非常低（来自残留的垂体组织或间脑来源），血浆皮质酮水平相似的未完全肾上腺切除的大鼠在VMH损伤后体重增加量相同。得出的结论是，肾上腺糖皮质激素在VMH综合征中主要起允许作用，肥胖表现仅需要极低水平的此类激素。
