Surmely J F, Voirol M J, Stefanoni N, Assimacopoulos-Jeannet F, Giacobino J P, Jéquier E, Gaillard R C, Tappy L
Institute of Physiology, Faculty of Medicine, University of Lausanne, Switzerland.
Int J Obes Relat Metab Disord. 1998 Sep;22(9):923-6. doi: 10.1038/sj.ijo.0800696.
To assess the effects of intracerebroventricular (i.c.v.) leptin administration on rats fed ad libitum or fasted on 3H GDP binding to brown adipose tissue (BAT).
Groups of 5-6 ten-week-old male Wistar rats.
An i.c.v. cannula was inserted and unilateral denervation of interscapular brown adipose tissue (BAT) was performed 5 d before each study. Thereafter, leptin was infused i.c.v. during 72 h while rats were fed ad libitum or fasted. Vehicle-infused, pair-fed or fasted rats were used as controls.
3H GDP binding to innervated and denervated BAT mitochondria.
3H GDP binding to innervated or denervated BAT of rats fed ab libitum compared to vehicle-infused, pair-fed rats was not increased by i.c.v. leptin. 3H GDP binding was lower in fasted than in fed rats, and the difference was larger in innervated than denervated BAT. I.c.v. leptin increased 3H GDP binding by 30% in innervated, and by 51% in denervated BAT (P < 0.05) in fasted rats.
I.c.v. leptin does not increase 3H GDP binding to BAT of rats fed ad libitum compared to pair-fed (food-restricted) rats. In contrast, i.c.v. leptin produces a mild stimulation of 3H GDP binding to BAT of fasted rats. This effect is not mediated by the sympathetic nervous system, because it is observed in both innervated and denervated BAT. These results are compatible with the concept that, in fasting rats, the decrease in leptin secretion contributes to the reduction in 3H GDP binding to BAT mitochondria.
评估脑室内注射瘦素对自由进食或禁食大鼠棕色脂肪组织（BAT）中³H GDP结合的影响。
每组5 - 6只十周龄雄性Wistar大鼠。
在每次研究前5天插入脑室内插管，并对肩胛间棕色脂肪组织进行单侧去神经支配。此后，在大鼠自由进食或禁食期间，脑室内注入瘦素72小时。注入溶剂、配对喂养或禁食的大鼠作为对照。
³H GDP与去神经和未去神经支配的BAT线粒体的结合情况。
与注入溶剂、配对喂养的大鼠相比，自由进食大鼠脑室内注射瘦素后，³H GDP与去神经或未去神经支配的BAT的结合并未增加。禁食大鼠的³H GDP结合低于进食大鼠，且这种差异在未去神经支配的BAT中比去神经支配的BAT中更大。在禁食大鼠中，脑室内注射瘦素使未去神经支配的BAT中³H GDP结合增加30%，使去神经支配的BAT中³H GDP结合增加51%（P < 0.05）。
与配对喂养（食物受限）的大鼠相比，自由进食大鼠脑室内注射瘦素不会增加³H GDP与BAT的结合。相反，脑室内注射瘦素对禁食大鼠的BAT中³H GDP结合有轻度刺激作用。这种作用不是由交感神经系统介导的，因为在去神经和未去神经支配的BAT中均观察到该现象。这些结果与以下概念相符，即在禁食大鼠中，瘦素分泌的减少导致³H GDP与BAT线粒体结合的减少。
