Which of the following statement is not true about glomerular basement membrane?
(A) Type III collagen is present (B) Glomerular basement membrane is stained with PAS (C) Glomerular basement membrane acts as filtration barrier (D) Glomerular basement membrane is involved in charge dependent filtration
(A) Ans. a. Type III collagen is present Type IV collagens (not the type HI collagen) are the main components of the basement membrane, together with laminin."The basement membrane is synthesized by contributions from the overlying epithelium and underlying mesenchymal cells, forming a flat lamellar "chicken wire" mesh (although labeled as a membrane; it is quite porous). The major constituents are amorphous nonfibrillar type IV collagen and lantinin." '"Type IV collagens have long but interrupted triple-helical domains and form sheets instead of fibrils; they are the main components of the basement membrane, together with laminin