One other function of the capillaries in peritubular capillary?

Exchange of nutrients and waste products between the blood and the renal tubular cells.

The capillaries in the peritubular capillary network are responsible for the exchange of nutrients and waste products between the blood and the renal tubular cells. The nutrients that are filtered out of the blood by the glomerulus are reabsorbed into the blood by the renal tubular cells. The waste products that are produced by the renal tubular cells are secreted into the blood by the capillaries.