View source for Renal corpuscle

{{short description|Blood-filtering component of the nephron of the kidney}}
{{Refimprove|date=October 2017}}
{{Infobox anatomy
| Name        = Renal corpuscle 
| Latin       = corpusculum renis
| Image       = Renal corpuscle-en.svg
| Caption     = The structure of the renal corpuscle. 
| Image2      = 2611 Blood Flow in the Nephron.jpg
| Caption2    = Diagram of the circulation related to a single glomerulus, associated tubule, and collecting system The renal corpuscle in the cortex (outer layer) of the kidney. At the top, the renal corpuscle containing the glomerulus. The filtered blood exits into the renal tubule as [[filtrate]], at right. At left, blood flows from the afferent arteriole (red), enters into the renal corpuscle and is filtered in the glomerulus; blood flows out of the efferent arteriole (blue).
| Precursor   =
| System      =
| Artery      =
| Vein        =
| Nerve       =
| Lymph       =
| Location = [[Nephron]] of the [[kidney]]
}}
A '''renal corpuscle''' (or '''Malpighian body'''<ref>{{Cite web|title=Renal corpuscle {{!}} anatomy|url=https://www.britannica.com/science/renal-corpuscle|access-date=2021-04-15|website=Encyclopedia Britannica|language=en}}</ref>) is the  blood-filtering component of the [[nephron]] of the [[kidney]].  It consists of a [[glomerulus (kidney)|glomerulus]] - a tuft of [[capillary|capillaries]] composed of [[endothelial cells]] - and a glomerular capsule known as [[Bowman's capsule]].<ref>{{Cite book|title=Principles of anatomy and physiology|last=J.|first=Tortora, Gerard|date=2010|publisher=John Wiley & Sons|others=Derrickson, Bryan.|isbn=9780470233474|edition=12th|location=Hoboken, NJ|pages=1024|oclc=192027371}}</ref>

==Structure==
{{See also|Glomerulus (kidney)|Bowman's capsule}}
The renal corpuscle is composed of two structures, the glomerulus and the Bowman's capsule.<ref>{{cite web|title=Renal corpuscle|url=https://www.merriam-webster.com/medical/renal%20corpuscle}}</ref> The glomerulus is a small tuft of [[capillary|capillaries]] containing two cell types.  Endothelial cells, which have large [[fenestra (histology)|fenestrae]], are not covered by diaphragms.  [[Mesangial cell]]s are modified smooth muscle cells that lie between the capillaries.  They regulate blood flow by their contractile activity and secrete [[extracellular matrix]], [[prostaglandins]], and [[cytokines]].  Mesangial cells also have phagocytic activity, removing proteins and other molecules trapped in the [[glomerular basement membrane]] or filtration barrier.

The Bowman's capsule has an outer parietal layer composed of simple squamous epithelium.  The visceral layer, composed of modified simple squamous epithelium, is lined by [[podocyte]]s,  [[podocyte foot processes]] (pedicels), that wrap around glomerular capillaries.  These pedicels interdigitate with pedicels of adjacent podocytes forming filtration slits.

There are two poles in the renal corpuscle, a '''vascular pole''' and a '''tubular pole'''.<ref name="ukidney">{{cite web |last1=Weinstein |first1=Jordan |title=Image 9: Normal glomerulus with tubular and vascular poles |url=https://ukidney.com/renal-pathology-tutorial/image-9-normal-glomerulus-with-tubular-and-vascular-poles |website=UKidney |access-date=22 September 2024 |language=en-gb |date=3 January 2018}}</ref> The vascular pole is a location of the glomerulus. At the vascular pole, the [[afferent arterioles]] and [[efferent arterioles]] enter and leave the glomerulus in the Bowman's capsule. The tubular pole is at the other end opposite to the vascular pole.  At the tubular pole, the [[proximal convoluted tubule]] arises.<ref>{{cite book |last=Mescher |first=Anthony L. |year=2016 |title=Junqueira's Basic Histology, 14th edition |publisher=Lange |page=397}}</ref>

==Function==
The renal corpuscle acts to filter blood. Fluid from blood in the glomerulus is collected in the Bowman's capsule to form "glomerular filtrate", which is then further processed along the nephron to form [[urine]]. It does this via a filtration barrier. The renal corpuscle filtration barrier is composed of: the fenestrated endothelium of glomerular capillaries, the fused basal lamina of endothelial cells and podocytes, and the filtration slits of the podocytes.  This barrier permits passage of water, ions, and small molecules from the bloodstream into Bowman's space (the space between the visceral and parietal layers).  Large and/or negatively charged proteins are prevented from passing into Bowman's space, thus retaining these proteins in the circulation.  The basal lamina is composed of 3 layers: lamina rara externa, lamina densa, and lamina rara interna.  The lamina rara externa is adjacent to the podocyte processes.  The lamina densa is the central layer consisting of type IV collagen and laminin.  This layer acts as a  selective macromolecular filter, preventing the passage of large protein molecules into Bowman's space.  The lamina rara interna is adjacent to endothelial cells.  This layer contains [[heparan sulfate]], a negatively charged [[glycosaminoglycan]] that contributes to the electrostatic barrier of the glomerular filter.

==Eponym==
A renal corpuscle is also known as a ''Malpighian corpuscle'', [[eponym|named after]] [[Marcello Malpighi]] (1628–1694), an Italian [[physician]] and [[biologist]].  This name is no longer widely used, probably to avoid confusion with a [[White pulp|Malpighian corpuscle]] in the [[spleen]].

==Additional images==
<gallery>
 File:Gray1130.svg|Image showing the main components of the renal corpusle. [[Glomerulus]] is red; [[Bowman's capsule]] is pink.
 File:Glomerular Physiology.png|Outline of function of renal corpuscle
</gallery>

==References==
{{Reflist}}

==External links==
{{commons category|Renal corpuscle}}
* {{BUHistology|16003loa}}
* {{LoyolaMedEd|Histo/practical/kidney/hp16-53.html}}

{{kidney}}

{{DEFAULTSORT:Renal Corpuscle}}
[[Category:Kidney anatomy]]