Increased expression of beta-catenin in brain microvessels of a segmentally trisomic (Ts65Dn) mouse model of Down syndrome.

We examined the distribution of beta-catenin and endogenous blood serum albumin at the ultrastructural level in blood microvessels (capillaries) from brains of control and trisomic Ts65Dn mice. Morphological examination revealed an increased immunolabeling for beta-catenin in endothelial substructures of the capillary network, such as intercellular junctions, cytoplasm, and nuclei. These immunosignals were significantly increased in all endothelial substructures from trisomic mice.

Immunogold study of effects of prenatal exposure to lipopolysaccharide and/or valproic acid on the rat blood-brain barrier vessels.

The involvement of blood microvessels, representing the anatomic site of the blood-brain barrier (BBB), in brain damage induced by prenatal exposure to lipopolysaccharide (LPS) and/or valproic acid (VPA) was studied in four-week-old rats. The immunogold procedure was applied for localization at the ultrastructural level of endogenous albumin and glucose transporter (GLUT-1) in three brain regions: cerebral cortex, cerebellum and hippocampus. Four groups of rats were used: (1) untreated control, (2) prenatally VPA-treated, (3) prenatally LPS-treated, and (4) prenatally LPS- and VPA-treated.

Immunogold study of altered expression of some interendothelial junctional molecules in the brain blood microvessels of diabetic scrapie-infected mice.

Quantitative immunogold procedure was used to study the distribution of molecular components of interendothelial junctions in blood-brain barrier (BBB) microvessels of scrapie infected SJL/J hyperglycemic mice showing obesity and reduced glucose tolerance. Samples of brain (fronto-parietal cerebral cortex and thalamo-hypothalamic region) obtained from hyperglycemic (diabetic) mice and from non- infected, normoglycemic (non-diabetic) SJL/J mice, were processed for immunocytochemical examination. The localization of the following tight junction (TJ)-associated proteins was studied: occludin as an integral membrane (transmembrane) protein, and zonula occludens one (ZO-1) as a peripheral protein.

Immunogold localization of tight junctional proteins in normal and osmotically-affected rat blood-brain barrier.

The distribution of molecular components of interendothelial tight junctions (TJs) was studied in rat blood-brain barrier (BBB) microvessels, using immunogold cytochemistry applied to electron microscopy. Samples of rat brains, both normal (unaffected) and osmotically-affected (1, 5, and 30 min after intracarotid infusion of 1.8 M L(+)arabinose), were processed for immunocytochemical localization of TJ-specific integral membrane (occludin, JAM-1, claudin-5) and peripheral (ZO-1) protein molecules.