Hauger R, Hulihan-Giblin B, Angel I, Luu M D, Janowsky A, Skolnick P, Paul S M
Brain Res Bull. 1986 Feb;16(2):281-8. doi: 10.1016/0361-9230(86)90043-2.
Binding sites for 3H-amphetamine in the hypothalamus may mediate the anorectic actions of amphetamine and related phenylethylamines. To investigate further the role of these sites in the central control of appetite, the binding of 3H-amphetamine to the hypothalamus and brainstem was measured following food deprivation and refeeding, the onset of genetic obesity, or the administration of 2-deoxy-D-glucose. Food deprivation for 24 to 72 hours reduced the Bmax for 3H-amphetamine binding in the hypothalamus and brainstem but not in other brain areas or peripheral tissues. The decrease in hypothalamic and brainstem 3H-amphetamine binding observed following food deprivation was time-dependent and rapidly reversed by brief refeeding with either rat chow or a 10% glucose solution. Moreover the changes in 3H-amphetamine binding were highly correlated to corresponding alterations in blood glucose concentration. Furthermore, D-glucose, but not L-glucose increases the number of hypothalamic 3H-amphetamine binding sites when administered in vivo or when added to hypothalamic slices in vitro. These data suggest that the 3H-amphetamine binding site in the hypothalamus and (or) brainstem may be coupled to a central "glucostat."
下丘脑内3H-苯丙胺的结合位点可能介导了苯丙胺及相关苯乙胺类药物的食欲抑制作用。为了进一步研究这些位点在食欲中枢控制中的作用,在禁食和再喂食、遗传性肥胖症发病或给予2-脱氧-D-葡萄糖后,测定了3H-苯丙胺与下丘脑和脑干的结合情况。禁食24至72小时可降低下丘脑和脑干中3H-苯丙胺结合的最大结合容量(Bmax),但其他脑区或外周组织不受影响。禁食后下丘脑和脑干中3H-苯丙胺结合的减少具有时间依赖性,用大鼠饲料或10%葡萄糖溶液短暂再喂食可迅速逆转。此外,3H-苯丙胺结合的变化与血糖浓度的相应改变高度相关。此外,D-葡萄糖而非L-葡萄糖在体内给药或体外添加到下丘脑切片时,会增加下丘脑3H-苯丙胺结合位点的数量。这些数据表明,下丘脑和(或)脑干中的3H-苯丙胺结合位点可能与中枢“葡萄糖稳态调节器”相耦联。