Rollins Bethany L, Stines Samuel G, King Bruce M
Department of Psychology, University of New Orleans, New Orleans, LA 70148, United States.
Physiol Behav. 2006 Sep 30;89(2):139-45. doi: 10.1016/j.physbeh.2006.05.015. Epub 2006 Jul 12.
Previous studies have shown that lesions of the posterodorsal amygdala result in hyperphagia and obesity in female rats. In the present study, lesions of the stria terminalis at its most dorsal point (before it separates into dorsal and ventral components) also resulted in hyperphagia and excessive weight gains in female rats compared to female rats with sham lesions, as did coronal knife cuts anterior to the ventromedial hypothalamus. Identical lesions and knife cuts did not elevate food intake or weight gains in male rats compared to male control animals. Examination of the anterograde degeneration with the amino-cupric-silver method in the brains of two female rats with hypothalamic knife cuts revealed degenerating terminals in the capsule of the ventromedial hypothalamus and in the premammillary nuclei, two classic indicators of damage to the dorsal component of the stria terminalis. No degenerating axon terminals were observed in the paraventricular nucleus. Differences from previous studies that used male rats were attributed to a sex difference for the effects of amygdaloid and ventromedial hypothalamic lesions. It is proposed that the posterodorsal amygdala, dorsal component of the stria terminalis, and ventromedial hypothalamus are part of an inhibitory pathway in the regulation of feeding behavior.
先前的研究表明，雌性大鼠的后背部杏仁核损伤会导致食欲亢进和肥胖。在本研究中，终纹床核在其最靠背部的位置（在它分为背侧和腹侧部分之前）受到损伤，与假手术损伤的雌性大鼠相比，同样导致了雌性大鼠食欲亢进和体重过度增加，下丘脑腹内侧核前方的冠状刀切割也产生了同样的结果。与雄性对照动物相比，相同的损伤和刀切割并未提高雄性大鼠的食物摄入量或体重增加。用氨基铜银法对两只接受下丘脑刀切割的雌性大鼠大脑进行顺行性变性检查发现，下丘脑腹内侧核的被膜和乳头前核中有变性终末，这是终纹床核背侧部分受损的两个典型指标。在室旁核中未观察到变性轴突终末。与之前使用雄性大鼠的研究结果不同，这归因于杏仁核和下丘脑腹内侧核损伤效应的性别差异。有人提出，后背部杏仁核、终纹床核的背侧部分和下丘脑腹内侧核是调节进食行为的抑制性通路的一部分。
