Chapter 11: Urinary system
Renal blood supply
The cortex of the kidney receives the majority of renal blood flow. The renal artery enters at the hilum of the kidneys and branches into the interlobar artery. The interlobar artery then travels between the pyramids and continues as arcuate artery, which arches along the corticomedullary junction. The interlobular artery is a stem off of the arcuate artery and travels through the cortex towards the capsule.
As the interlobular artery ascends towards the cortex, branches of afferent arterioles are sent to each glomerulus. The afferent arterioles give rise to the capillaries that form the glomerulus. The glomerular capillaries reunite and form the efferent arteriole which exits at the vascular pole. The efferent arterioles of cortical nephrons give rise to the peritubular capillaries. As discussed previously, in the juxtamedullary nephrons, the peritubular capillaries form the ascending and descending vasa recta. The peritubular capillaries and vasa recta then drain into the interlobular vein, which unites with others to form the arcuate vein. Then the interlobular vein exits the kidney as the renal vein.