The kidneys are connected with two major blood vessels: the renal artery and the renal vein. In the kidney, the renal arteries divide into several arterioles. These arterioles form a mesh-like network in the glomerulus. The blood under high pressure enters this network and is filtered through the capillary network of the glomerulus. These capillaries join together and form the renal vein which collects the filtered blood and returns it to the heart.