Vasa recta (kidney): Difference between revisions

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Vasa Recta (Kidney)

The vasa recta are a series of straight capillaries in the medulla of the kidney. They lie parallel to the loop of Henle and play a crucial role in the kidney's ability to concentrate urine.

Structure

The vasa recta are part of the renal circulation and are derived from the efferent arterioles of the juxtamedullary nephrons. These capillaries descend into the renal medulla, forming a network around the loop of Henle. The vasa recta are divided into two parts: the descending vasa recta and the ascending vasa recta.

Descending Vasa Recta

The descending vasa recta are thin-walled capillaries that carry blood from the cortex into the medulla. They are permeable to water, allowing water to leave the blood and enter the interstitial fluid of the medulla.

Ascending Vasa Recta

The ascending vasa recta carry blood back towards the cortex. They are less permeable to water but allow solutes to be reabsorbed into the blood, helping to maintain the osmotic gradient in the medulla.

Function

The primary function of the vasa recta is to supply blood to the medulla and to participate in the countercurrent exchange mechanism. This mechanism is essential for the concentration of urine. As blood flows through the vasa recta, it helps to maintain the osmotic gradient established by the loop of Henle, allowing for the reabsorption of water and solutes.

Clinical Significance

The vasa recta are important in the pathophysiology of certain kidney diseases. For example, damage to these capillaries can lead to impaired urine concentration and contribute to conditions such as acute kidney injury.

Related Pages

References

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-'''Vasa recta''' are the series of straight capillaries in the [[medulla]] of the [[kidney]]. They are surrounded by the [[loop of Henle]] and are an integral part of the [[urine]] concentration mechanism in the kidney. The vasa recta, along with the loop of Henle, form the [[countercurrent multiplier system]] which helps to maintain the [[osmotic gradient]] in the medulla of the kidney.
+== Vasa Recta (Kidney) ==
-==Structure==
+The '''vasa recta''' are a series of straight capillaries in the [[medulla]] of the [[kidney]]. They lie parallel to the [[loop of Henle]] and play a crucial role in the kidney's ability to concentrate urine.
-The vasa recta are long, straight capillaries that parallel the loop of Henle in the medulla of the kidney. They originate from the [[efferent arterioles]] serving the [[glomeruli]] of the [[juxtamedullary nephrons]], and carry blood at a slow rate to allow for [[osmosis]] and [[diffusion]] of solutes.
-==Function==
+== Structure ==
-The primary function of the vasa recta is to maintain the [[osmotic gradient]] in the medulla of the kidney. This gradient is essential for the kidney's ability to produce concentrated urine. The vasa recta achieve this by a process known as [[countercurrent exchange]].
-In countercurrent exchange, the vasa recta's blood flow is slow, allowing for maximal time for osmosis and diffusion of solutes. As the blood descends into the medulla, it loses water and gains salt, maintaining the high osmolarity of the medulla. As the blood ascends, it gains water and loses salt, again maintaining the osmotic gradient.
+The vasa recta are part of the [[renal circulation]] and are derived from the [[efferent arterioles]] of the [[juxtamedullary nephrons]]. These capillaries descend into the renal medulla, forming a network around the loop of Henle. The vasa recta are divided into two parts: the descending vasa recta and the ascending vasa recta.
-==Clinical significance==
+=== Descending Vasa Recta ===
-Abnormalities in the vasa recta can lead to kidney diseases such as [[renal failure]]. In conditions such as [[diabetes mellitus]], the high blood sugar levels can damage the vasa recta, leading to [[nephropathy]].
+The descending vasa recta are thin-walled capillaries that carry blood from the cortex into the medulla. They are permeable to water, allowing water to leave the blood and enter the interstitial fluid of the medulla.
+=== Ascending Vasa Recta ===
+The ascending vasa recta carry blood back towards the cortex. They are less permeable to water but allow solutes to be reabsorbed into the blood, helping to maintain the osmotic gradient in the medulla.
+== Function ==
+The primary function of the vasa recta is to supply blood to the medulla and to participate in the countercurrent exchange mechanism. This mechanism is essential for the concentration of urine. As blood flows through the vasa recta, it helps to maintain the osmotic gradient established by the loop of Henle, allowing for the reabsorption of water and solutes.
+== Clinical Significance ==
+The vasa recta are important in the pathophysiology of certain kidney diseases. For example, damage to these capillaries can lead to impaired urine concentration and contribute to conditions such as [[acute kidney injury]].
+== Related Pages ==
-==See also==
-* [[Kidney]]
 * [[Nephron]]
-* [[Renal physiology]]
+* [[Loop of Henle]]
+* [[Renal circulation]]
 * [[Countercurrent exchange]]
-[[Category:Kidney]]
+== References ==
-[[Category:Anatomy]]
-[[Category:Physiology]]
+{{Reflist}}
-{{anatomy-stub}}
+[[Category:Kidney anatomy]]
+[[File:Kidney nephron.png|thumb|Diagram of a kidney nephron, showing the vasa recta.]]