Morphological investigations of glucose uptake in the mouse hippocampus.

近年来，人们对大脑中能量代谢和神经活动之间的关系越来越感兴趣。我们一直在研究影响小鼠海马体葡萄糖摄取的因素。我们将在此报告海马层各区域的微血管、层粘连蛋白、胰岛素、胰岛素受体和葡萄糖转运体的密度。墨汁灌流的微血管密度以分子陷窝层最高，透明层和齿状颗粒细胞层最低。在锥体细胞层中，CA3a区的微血管密度明显高于CA1区。虽然免疫组织化学染色的层粘连蛋白分布与微血管一致，但锥体细胞层和颗粒细胞层也有免疫阳性反应。相反，胰岛素和胰岛素受体主要分布在颗粒层和锥体层，而在腔隙分子层分布最少，提示胰岛素与葡萄糖向脑的转运无关。负责促进脑内葡萄糖转运的葡萄糖转运蛋白的免疫组织化学反应不仅在微血管壁呈强阳性，而且在陷窝分子层的实质组织中也呈强阳性。以NO2为衰老模型的重度贫血症(30min)对海马区星形胶质细胞的突触密度和形态变化没有任何影响。

In recent years, there has been a growing interest in the relationships between energy metabolism and neural activity in the brain. We have been investigating the factors responsible for glucose uptake in the mouse hippocampus. We will report here the densities of microvessel, laminine, insulin, insulin receptor and glucose transporter in each laminar region of the hippocampus. The highest density of perfused microvessels with indian ink was found in the stratum lacunosum - moleculare, as compared with other regions, and lowest values were found in the stratum lucidum and dentate granular cell layer. Among pyramidal cell layers, microvessel density of the sector CA3a was significantly higher than that of the CA1. Although laminine distributions stained immunohistochemically were consistent with that of microvessels, immuno - positive reactions were also seen in the pyramidal and granular cell layer. By contraries, insulin and insulin receptors were intensively distributed in the stratum granulare and pyramidale, while they were lowest in the stratum lacunosum - moleculare, suggesting that the insulin have no dealings with the glucose transport into the brain. The immunohistochemical reactions of glucose transporter, responsible for facilitated glucose transport in the brain, were not only highly positive in the microvessel wall, but also in the parenchymal tissue in the stratum lacunosum - moleculare. The severe anemic hypoxia(NO_2 for30 minutes), used for the model of aging, did not any influence to the synaptic densities and morphological changes of astroglial cells in the hippocampus.