The renal stroma is composed of loose connective tissue and contains blood vessels, capillaries, nerves, and lymphatics.
The renal arteries are all end arteries.
The renal circulation. (Reproduced, with permission, from Leaf A, Cotran RS: Renal Pathophysiology. Oxford University Press, 1976.)
A: The posterior branch of the renal artery and its distribution to the central segment of the posterior surface of the kidney. The renal artery divides into anterior and posterior branches. The posterior branch supplies the midsegment of the posterior surface.
B: Branches of the anterior division of the renal artery supplying the entire anterior surface of the kidney as well as the upper and lower poles at both surfaces. The anterior branch supplies both upper and lower poles as well as the entire anterior surface.The segmental branches lead to interlobar,
interlobar arteries, which travel in the columns of Bertin (between the pyramids) and then arch along the base of the pyramids (arcuate arteries). These arteries then divide as interlobular arteries. From these vessels, smaller (afferent) branches pass to the glomeruli. From the glomerular tuft, efferent arterioles pass to the tubules in the stroma.
which in turn give rise to arcuate arteries at the junction between the renal cortex and medulla (Figure 29-8). Arcuate arteries further divide into interlobular branches that eventually supply each nephron via a single afferent arteriole. Blood from each glomerular capillary tuft is drained via a single efferent arteriole and then travels alongside adjacent renal tubules in a second peritubular system of capillaries. In contrast to the glomerular capillaries, which favor filtration, peritubular capillaries are primarily “reabsorptive.” Venules draining the second capillary plexus finally return blood to the inferior vena cava via a single renal vein on each side.
C: The lateral convex margin of the kidney. Brödel's line, which is 1 cm from the convex margin, is the bloodless plane demarcated by the distribution of the posterior branch of the renal artery.
Venous
The renal veins are paired with the arteries, but any of them will drain the entire kidney if the others are tied off.
Although the renal artery and vein are usually the sole blood vessels of the kidney, accessory renal vessels are common and may be of clinical importance if they are so placed to compress the ureter, in which case hydronephrosis may result.
Nerve Supply
The renal nerves derived from the renal plexus accompany the renal vessels throughout the renal parenchyma.
Lymphatics
The lymphatics of the kidney drain into the lumbar lymph nodes.