Glomerular basement membrane

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Glomerular basement membrane
Glomerulus. (Diagram in French, but "Membrane basale glomerulaire et ses podocytes" labeled near center.)
MeSH	glomerular+basement+membrane
Dorlands/Elsevier	m_08/12522684

The glomerular basement membrane is the basal laminal portion of the glomerulus which performs the actual filtration though the filtration slits between the podocytes , separating the blood on the inside from the filtrate on the outside. It is a fusion of the endothelial cell and podocyte basal laminas. ^[1]

Contents 1 Layers 2 Pathology 3 See also 4 References 5 External links

[edit] Layers

The GBM contains three layers: ^[2]

Layer	Location	Composition	Function
lamina rara externa	adjacent to podocyte processes	heparan sulfate	blocks by charge
lamina densa	dark central zone	type 4 collagen and laminin	blocks by size (MW > 69,000)
lamina rara interna	adjacent to endothelial cells	heparan sulfate	blocks by charge

[edit] Pathology

• Goodpasture's syndrome is also known as "anti-glomerular basement membrane disease". Capillaries become inflamed as a result of damage to the basement membrane by antibodies.

• Nephrotic syndrome is a change in the structure of the glomerular filtration mechanism usually in the glomerular basement membrane. Some symptoms include proteinuria, hypoalbuminaemia, oedema, and hyperlipidemia.

• Diabetic glomerulosclerosis is a thickening of the basement membrane, which can become up to 4-5 times thicker than normal. Can be caused by insulin deficiency or resultant hyperglycemia.

[edit] See also

• basement membrane
• nephrin

[edit] References

1. ^ Physiology at MCG 7/7ch04/7ch04p07 - "Basement Membrane"
2. ^ JCI - New articles published

[edit] External links

• MeSH glomerular+basement+membrane
• "The GBM and its disorders" at dmed.ed.ac.uk
• Histology at harvard.edu
• Structure at wramc.army.mi

v • d • e Urinary system – Kidney Layers Renal fascia • Renal capsule • Renal cortex  (Renal column) • Renal medulla (Renal sinus, Renal pyramids, medullary interstitium) • Renal lobe • Cortical lobule • Medullary ray • Nephron Afferent circulation Renal artery → Segmental arteries → Interlobar arteries → Arcuate arteries → Cortical radial arteries → Afferent arterioles → Renal corpuscle (Glomerulus, Bowman's capsule) Renal tubule Proximal tubule → Loop of Henle (Descending, Thin ascending, Thick ascending) → Distal convoluted tubule → Connecting tubule → Collecting ducts → Duct of Bellini → Renal papilla → Minor calyx → Major calyx → Renal pelvis → Ureter Efferent circulation Glomerulus → Efferent arterioles → Peritubular capillaries / Vasa recta → Arcuate vein → Interlobar veins → Renal vein Juxtaglomerular apparatus Macula densa • Juxtaglomerular cells • Extraglomerular mesangial cell Filtration Glomerular basement membrane • Podocyte • Filtration slits • Intraglomerular mesangial cell • Tubular fluid Renal physiology Acid base physiology • Fluid balance