efferent arteriole

anatomy

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Last updated

June 26, 2026

Quick Summary

The efferent arteriole is a blood vessel within the kidney that carries blood away from the glomerulus. It is formed by the merging of capillaries within the glomerulus, where blood filtration occurs.1

Key facts about the efferent arteriole:
* Origin: Formed from the capillaries within the glomerulus.
* Function: Carries blood away from the glomerulus.
* Size: Thinner than the afferent arteriole, which carries blood to the glomerulus.1
* Role in Filtration: The tone (constriction or dilation) of the efferent arteriole influences glomerular pressure and filtration rate. Constriction of the efferent arteriole can increase glomerular pressure and filtration.2
* Blood Supply: After leaving the glomerulus, efferent arterioles typically redivide into a second set of capillaries that supply blood to the renal tubules.1

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renal system
Arteries and arterioles
…afferent arteriole to become the efferent arterioles carrying blood away from the glomeruli. The afferent arterioles are almost twice as thick as the efferent arterioles because they have thicker muscular coats, but the sizes of their channels are almost the same.
Read More
…afferent arteriole to become the efferent arterioles carrying blood away from the glomeruli. The afferent arterioles are almost twice as thick as the efferent arterioles because they have thicker muscular coats, but the sizes of their channels are almost the same.
Read More