Published on July 8, 2007
Adrenal (Suprarenal) Gland R. Kalliecharan
Embryology and Location One lies superior to each Kidney Each is composed of an outer region, the Cortex and an inner region, the Medulla Cortex is derived from intermediate mesoderm whereas the Medulla is derived from neural crest cells
Blood Supply Several arteries supply blood to adrenals. They form a subcapsular plexus from which arise 3 groups of vessels 1. arteries of capsule, 2. arteries of cortex which form capillaries in the cortex. These enter into the medulla . 3. arteries of medulla which form capillaries in the medulla. Thus, medulla has a dual blood supply. The medullary veins that form join to form the adrenal vein
Histology of Cortex • Cortex has 3 concentric layers : • A) zona glomerulosa , beneath capsule , is composed of columnar or pyramidal cells and arranged as rounded or arched cords • B) zona fasciculata ( the middle layer),cells are arranged in straight cords ,1 or 2 cells thick and perpendicular to the surface. • C) zona reticularis, cells arranged in an anastomosing network. Lipofuscin granules and pyknotic nuclei are present
Hormones of Cortex • Glomerulosa cells secrete the mineralocorticoid hormone---aldosterone under control of angiotensin II • Fasciculata cells secrete glucocorticoids--- cortisol under control of ACTH • Reticularis cells secrete mainly steroid sex hormones (dehydroepiandrosterone) under control by ACTH
Hormones Cells from Cortex do not store their hormones in membrane-bound granules. They syn and secrete only on demand. They can diffuse freely across the P M since they are steroids Collaboration occurs between SER and Mito in the production of steroidal hormones
Histology of Adrenal Medulla • Composed of cords or clumps of cells called chromaffin cells.These can acquire a brown color which is due to oxidation of catecholamines by chromic salts • Chromaffin cells are modified sympathetic postganglionic neurons without processes. Cells are surrounded by capillaries • Cells have lots of membrane-bound secretory granules with either epinephrine or norepinephrine
Histology-Medulla • Epinephrine secreting cells (80%) have smaller granules that are less electron dense • Norepinephrine secreting cells (20%) have larger granules and more electron dense ; an electron – lucent layer is present • Catecholamine hormones are syn from tyrosine. Norepinephrine that is formed leaves the granule to enter cytosol • Glucocorticoids transported from cortex to medulla via cortical capillaries stimulates syn of phenylethanolamine N- methyltransferase(PNMT) to convert norepinephrine to epinephrine
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids ...
The suprarenal glands, also known as adrenal glands, belong to the endocrine system. They are a pair of triangular-shaped glands, each about 2 in.
The supraneal, or adrenal, glands are a pair of glands that secrete hormones directly into the bloodstream. Each gland can be divided into two distinct organs.
Adrenal gland disorders, such as Cushing's Syndrome and Addison's Disease, happen when your glands make too much or not enough hormones.
What are the symptoms of adrenal gland disorders? ... When the adrenal glands produce too many hormones, the symptoms vary depending on the disorder.
When you think of the adrenal glands (also known as suprarenal glands), stress might come to mind. And rightly so—the adrenal glands are arguably best ...
An adrenal tumor or adrenal mass is any benign or malignant neoplasms of the adrenal gland, several of which are notable for their tendency to overproduce ...
What are the treatments for adrenal gland disorders? Skip sharing on social media links. Share this: Health care providers use a variety of ...
The suprarenal gland (adrenal gland) is located at the top of each kidney; therefore each person has two suprarenal glands. The suprarenal glands are ...
Tumors can affect adrenal glands. Most adrenal gland tumors are benign. Types of tumors include Neuroblastoma and Pheochromocytoma.