basaalmembraaniin

Basaalmembraaniin is the Dutch term used to refer to basal membranes, the thin sheets of extracellular matrix that lie at the interface between epithelium or endothelium and the underlying connective tissue. The term is used in histology and pathology to discuss multiple basal membranes in different tissues.

Basal membranes consist of two layers: the basal lamina, produced mainly by epithelial or endothelial cells, and, in many tissues, a reticular lamina produced by the surrounding connective tissue. The basal lamina contains laminin, type IV collagen, nidogen, and proteoglycans such as perlecan. The reticular lamina contains additional collagen types and fibronectin. In the kidney, the glomerular basement membrane is a specialized basal membrane essential for filtration.

Function: Basal membranes provide structural support and separate epithelium from connective tissue, regulate the passage of molecules, and influence cell behavior through interactions with integrins and other receptors. They guide cell migration during development and play a role in wound healing and tissue regeneration.

Clinical significance: Abnormalities in basal membranes are linked to diseases such as Alport syndrome (collagen IV defects) and Goodpasture syndrome (autoantibodies against basement membrane components). Diabetic nephropathy often involves thickening of renal basement membranes. Mutations in laminin, collagen IV, and other components can affect tissue integrity.

See also: basement membrane, basal lamina, laminin, collagen IV.