Intraglomerular mesangial cell

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Intraglomerular mesangial cells are specialized pericytes located among the glomerular capillaries within a renal corpuscle of a kidney.

There are three primary functions of intraglomerular mesangial cells: filtration, structural support, and phagocytosis.

Contents 1 Filtration and structure 2 Phagocytosis 3 See also 4 External links

[edit] Filtration and structure

Glomerular capillaries consist of endothelial cells with large fenestrations, and are therefore very permeable ("leaky") for most solutes in blood plasma.

They provide structural support for and regulate blood flow of the glomerular capillaries by their contractile activity. The initiation of contraction of mesangial cells is similar to that of smooth muscle. Contraction of mesangial cells is coupled by that of basement membrane of the endothelium of glomerular capillaries, causing decrease in surface area of basement membrane. Thus, decreasing glomerular filtration rate.

They are also major contributors to the extracellular matrix which contains fibronectin, type IV collagen, perlecan, and laminin.

[edit] Phagocytosis

Mesangial cells also phagocytose glomerular basal lamina components and immunoglobulins. They are an unusual example of phagocytic cells derived from smooth muscle and not monocytes.

[edit] See also

• mesangium
• extraglomerular mesangial cells

[edit] External links

• Histology at BU 16006loa

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