Some of these fibers will synapse at the celiac ganglion and post-synaptic fibers of the celiac ganglion will innervate the blood vessels supplying the suprarenal gland. The fibers converge after bypassing the sympathetic trunk, forming the greater splanchnic nerve. These nerve fibers leave the intermediolateral cell column of the lateral horn of the spinal cord from the T5 – T8 segments of the spinal cord and bypass the paravertebral sympathetic ganglion chain. On the other hand, the suprarenal medulla is innervated by type B (medium diameter, myelinated) preganglionic nerve fibers. ACTH subsequently stimulates the respective cortical zones to produce corticosteroids. The cortex is activated by adrenocorticotropic hormone (ACTH) from the anterior pituitary gland. The action of the suprarenal gland is regulated both by neuronal and hormonal stimulation. Here, suprarenal androgens are produced, which serve as precursors for testosterone. This layer is responsible for secreting glucocorticoids to increase the overall blood glucose level in an effort to provide more energy for a system under stress.įinally, the zona reticularis consists of smaller cells that stain darker relative to cells of the aforementioned layers. It is made up of pale staining vacuolated cells arranged in parallel rows. Zona fasciculata is significantly thicker than the other two cortical layers. Aldosterone regulates the uptake of water in the distal convoluted tubules, which consequently alters the body’s blood pressure. The zona glomerulosa is comprised of small rounded cells that are responsible for secreting mineralocorticoids such as aldosterone. The cortex can be subdivided into the zona glomerulosa, the zona fasciculata and the zona reticularis. There is an outer fatty capsule just deep to the renal fascia that functions as an added protective layer.ĭeep to the capsule, is the suprarenal cortex. However, only two of these layers are of homeostatic significance.

Essentially the gland is divided into three layers.

Where's your adrenal gland