The adrenal gland has two layers: the adrenal cortex (outer layer), which is derived from the mesoderm, and the adrenal medulla (inner layer), which is derived from neural crest cells. The lymphatics drain into the left aortic and the right caval lymph nodes. It receives its arterial supply from the superior, middle, and inferior suprarenal arteries and drains into the right and left suprarenal veins. The adrenal gland is a paired retroperitoneal organ located on the upper pole of each kidney.
