Blood-brain barrier glucose transporter is asymmetrically distributed on brain capillary endothelial lumenal and ablumenal membranes: an electron microscopic immunogold study.

摘要: It is generally assumed that there symmetric distribution of the glucose transporter on lumenal and ablumenal membranes brain capillary endothelial cell makes up blood-brain barrier (BBB) in vivo. However, presence tight junctions allows for asymmetric BBB plasma membrane proteins. Glucose isoform 1 (GLUT-1), principal at BBB, was assessed rat present studies using immunogold electron microscopy. The immunoreactive GLUT-1 protein membrane, cytoplasmic compartment 12%, 48%, 40%, respectively, no significant immunolabeling neuropil measurable. These suggest (i) asymmetrically distributed with an approximately 4-fold greater abundance as compared to membrane; (ii) 40% contained within space, which provides a mechanism rapid up-regulation by altered between compartments; (iii) labeling found antisera directed against protein. also mechanisms regulation transport from blood involve differential subcellular compartments cells.