Monocarboxylate transporter (MCT1) abundance in brains of suckling and adult rats: a quantitative electron microscopic immunogold study
Monocarboxylate transporter (MCT1) abundance in brains of suckling and adult rats: a quantitative electron microscopic immunogold study
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DOI：
10.1016/s0165-3806(98)00188-6
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发表时间：
1999-03-12
期刊：
影响因子：
--
通讯作者：
Drewes, LR
中科院分区：
文献类型：
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作者：
Leino, RL;Gerhart, DZ;Drewes, LR
能量底物跨脑血管内皮细胞的跨细胞转运是通过整合的膜载体蛋白完成的，如葡萄糖转运蛋白GLUT 1和单羧酸转运蛋白MCT 1。这些蛋白质的丰度可能因年龄和营养状况而异。在这项研究中，我们比较了MCT 1在哺乳期和成年大鼠大脑皮层中的表达，以确定前者是否比老年大鼠使用更多的单羧酸盐（如乳酸盐和酮体）作为燃料，相应地表达更多的MCT 1。使用电子显微镜免疫金方法，我们发现，17日龄乳鼠幼仔毛细血管内皮细胞膜上的MCT 1标记是成年大鼠的25倍。这种转运蛋白几乎均匀分布在管腔和近管腔膜中，内皮细胞质室中的免疫金颗粒不到10%。乳鼠也有15倍以上的免疫金颗粒与周细胞膜和19倍以上的标记膜与星形胶质细胞的尾脚附近的微血管。神经纤维网和脉络丛被轻轻标记。观察到一些MCT 1阳性星形胶质细胞和神经元细胞体，表明这些细胞活跃合成MCT 1。通过饮食或其他因素调节MCT表达的可能性可能对脑血管疾病和其他疾病的进展和治疗产生重要影响。(C)1999 Elsevier Science B.V.保留所有权利。
Transcellular transport of energy substrates across the vascular endothelial cells of the brain is accomplished by integral membrane carrier proteins, such as the glucose transporter GLUT1 and the monocarboxylic acid transporter MCT1. The abundance of these proteins may vary depending on age and nutritional status. In this study we compared the expression of MCT1 in cerebral cortex of suckling and adult rats to determine whether the former, which use considerably more monocarboxylates such as lactate and ketone bodies as fuel than do older rats, correspondingly express more MCT1 than adults. Using electron microscopic immunogold methods, we found that 17-day old suckling rat pups had 25 times more MCT1 labeling in the membranes of capillary endothelial cells than adults. This transporter was nearly equally distributed in luminal and abluminal membranes with less than 10% of the immunogold particles in the endothelial cytoplasmic compartment. The suckling rats also had 15 times more immunogold particles associated with pericyte membranes and 19 times heavier labeling of membranes associated with astrocytic end feet adjacent to microvessels. Neuropil and choroid plexus were lightly labeled. Some MCT1-positive astrocyte and neuron cell bodies were observed, suggesting active synthesis of MCT1 by these cells. The potential for regulation of expression of MCTs by dietary or other factors may have important consequences for the progression and treatment of cerebrovascular disorders and other diseases. (C) 1999 Elsevier Science B.V. All rights reserved.