Basement Membrane Type IV Collagen Molecules in the Choroid Plexus, Pia Mater and Capillaries in the Mouse Brain.

Abstract

We investigated the differential distribution of basement membrane type IV collagen a chains in the mouse brain by immunohistochemistry using a chain-specific monoclonal antibodies. Subendothelial basement membranes were found to contain alpha1 and alpha2 chains. Basement membranes surrounding smooth muscle cells on blood vascular walls were immunoreactive for alpha1 and alpha2 chains but not for alpha5 and alpha6 chains. Interestingly, the pia mater contained a thin basement membrane which was positive for alpha1, alpha2, alpha5, and alpha6 chains, suggesting that glia limitans superficialis coheres basement membranes containing [alpha1(IV)]2alpha2(IV) and [alpha5(IV)]2alpha6(IV) molecules. In contrast, capillaries always possessed thin basement membranes of [alpha1(IV)]2alpha2(IV) molecules. Cerebrospinal fluid is produced through filtration of blood at the choroid plexus, where two distinct basement membranes were detected by anti-al and anti-alpha2 antibodies. The subendothelial basement membrane appeared to consist of [alpha1(IV)]2alpha2(IV) molecules, whereas the subependymal basement membrane in the choroid plexus was strongly positive for alpha3, alpha4, and alpha5 chains, indicating that the filtering unit was composed of alpha3(IV)alpha4(IV)alpha5(IV) molecules. That the specific localizations of these molecules are shared by renal glomeruli and the choroid plexus leads us to hypothesize that the supramolecular network containing alpha3(IV) alpha4(IV)alpha5(IV) molecules may function as a permeability selective barrier.

Quantitative Proteome Analysis Reveals Increased Content of Basement Membrane Proteins in Arteries From Patients With Type 2 Diabetes Mellitus and Lower Levels Among Metformin Users

“…33 Basement membrane accumulation has most often been observed by electron microscopy, whereas biochemical data are scant; however, our results are compatible with the idea that at least some of the mechanisms behind macrovascular and microvascular complications in DM may be common. 2 In the arterial wall, the majority of the basement membrane material is situated around the vascular smooth muscle cells in tunica media, as previously reported, 34 as observed in this study. The most abundant proteins in basement membrane areas are type IV collagen and laminin, but also nidogen, fibulin-1, type XVIII collagen, and basement membrane heparan sulfate proteoglycan (perlecan) are part of the protein constituency.…”

Type IV Procollagen Missense Mutations Associated With Defects of the Eye, Vascular Stability, the Brain, Kidney Function and Embryonic or Postnatal Viability in the Mouse, Mus musculus: An Extension of the Col4a1 Allelic Series and the Identification of the First Two Col4a2 Mutant Alleles

“…The mutations were associated with abnormalities of the lens, the cornea, vascular stability, the brain, kidney function, and survival in the embryonic or the postnatal period. These observations are consistent with the ubiquitous expression of the Col4a1 and Col4a2 genes, with specific expression documented in the cornea, the lens, the lens capsule, and the retina (Kleppel and Michael 1990;Sarthy 1993;Cheong et al 1994;Qin et al 1997;Kelley et al 2002); capillaries (Bell et al 2001;Tilling et al 2002;Urabe et al 2002); the brain (Kleppel et al 1989;Pö schl et al 2004); the kidney (Desjardins et al 1990;Gunwar et al 1998;Boutaud et al 2000); and the embryonic membrane, Reichert's membrane, and the placenta (Kleppel et al 1989;Miner et al 2004;Pö schl et al 2004). The nine Col4a1 mutations extend the mouse allelic series as well as the five COL4A1 missense mutations in humans.…”

Growth conelike sensorimotor structures are characteristic features of postmigratory, premyelinating oligodendrocytes

“…Instead, merosin has been shown to stimulate the transition from process outgrowth to myelin sheath formation (Buttery and ffrench-Constant, 1999). The above findings are in good agreement with the behavior of postmigratory, premyelinating oligodendrocyte processes in vivo, that is, avoidance of collagen IV-covered blood vessels (Tilling et al, 2002;Urabe et al, 2002) and selective myelination of merosin-covered naked axons (Buttery and ffrench-Constant, 1999).…”