Manin M, Balage M, Larue-Achagiotis C, Grizard J
Laboratoire d'Etude du Métabolisme Azoté, INRA Clermont-Theix, Ceyrat, France.
J Neurochem. 1988 Dec;51(6):1689-95. doi: 10.1111/j.1471-4159.1988.tb01146.x.
The present study was performed to explore the role of exogenous insulin in CSF in the control of energy balance in the rat. For this purpose, adult male Sprague-Dawley rats carrying an indwelling cannula in the right lateral cerebral ventricle were infused for a maximum of 10 days with insulin (Actrapid) at various rates (starting at 0, 45, 85, 170, and 600 ng/day) or anti-insulin antibody (IgG fraction; diluted 1:10 wt/vol) with an osmotic minipump. All those treatments did not modify the growing rates; neither total daily food intake nor the circadian rhythm of food intake was further modified. The chronic insulin infusion starting at 600 ng/day resulted in a chronic significant increase in CSF insulin levels without changing the plasma insulin level. It failed to alter specific insulin binding sites to Triton X-100 solubilized microsomal membranes from various brain areas (cerebral cortex, olfactory bulbs, and lateral and medial hypothalami) at the end of the 5- or 10-day period of insulin infusion. Purification of insulin receptors on a wheat germ agglutinin did not reveal any further effect of insulin. From these results, it seems unlikely that the input to the brain insulin-effector systems could arise from CSF insulin.
本研究旨在探讨脑脊液中外源性胰岛素在大鼠能量平衡控制中的作用。为此，将右侧侧脑室留置套管的成年雄性Sprague-Dawley大鼠，用渗透微型泵以不同速率（起始剂量为0、45、85、170和600 ng/天）输注胰岛素（Actrapid）或抗胰岛素抗体（IgG组分；按重量/体积1:10稀释），最长输注10天。所有这些处理均未改变生长速率；每日食物总摄入量和食物摄入的昼夜节律也未进一步改变。从600 ng/天开始的慢性胰岛素输注导致脑脊液胰岛素水平慢性显著升高，而血浆胰岛素水平未改变。在胰岛素输注5天或10天结束时，它未能改变来自不同脑区（大脑皮层、嗅球以及下丘脑外侧和内侧）的Triton X-100溶解微粒体膜上的特异性胰岛素结合位点。在麦胚凝集素上纯化胰岛素受体未发现胰岛素有任何进一步作用。从这些结果来看，脑脊液胰岛素似乎不太可能是大脑胰岛素效应系统的输入来源。
