are the adrenal glands strictly nerve tissue
Overview of Adrenal Histology. The adrenal gland is encased in a connective tissue capsule that extends septae into the substance of the gland. The organ is richly vascularized and capsular blood vessels, nerves and lymphatics penetrate along with the connective tissue septae. The most distinctive feature of the adrenal is its partitioning into cortex and medulla. Adrenal Gland. These are a pair of glands, one associated with each kidney. They have an inner medulla and outer cortex, and there are different types of endocrine tissue in each. The embryological origin of the cortex, is similar to that of the gonads. The embryological origin of the medulla is the same as that of the sympathetic nervous system. The chromaffin cells, when stimulated by the sympathetic nervous system (see physiology section), secrete noradrenaline and adrenaline into the sinusoids, which are delivered by the bloodstream to the rest of the body. Diagram illustrating anatomy of adrenal glands - click to enlarge. The anterior part is made up of glandular tissue and is called adenohypophysis responsible for producing six hormones. The posterior part is strictly a nervous tissue and it stores ADH and oxytocin (hormones) which is produced by hypothalamus. It is called neurohypophysis. Nerve supply. The adrenal glands have a rich nerve supply. These nerves are derived from the coeliac plexus and the thoracic splanchnic nerves. The nerves supply the chromaffin cells of the medulla, but careful microscopy has shown that nerve trunks and plexuses may also appear in the cortical layers. The thyroid gland is the only slide you will see in which large circular structures (follicles, 1) are filled with a uniformly pink staining substance, the colloid (2) (in other tissues with such circular structures they appear empty inside). Features to know: 1  The irregular outermost layer of connective tissue is the capsule (1). 2  The next region deep to the capsule is the adrenal cortex (2-4), which itself is subdivided into 3 zones: 3  The first (outermost) layer of the cortex is the zona glomerulosa (2). 4  Next is the zona fasiculata  (3). adrenal cortex The outer portion of the adrenal glands that produces hormones essential to homeostasis. chromaffin The cells of the adrenal medulla that secrete adrenaline and noradrenaline in response to nervous stimulation. Endocrine glands do not have ducts. They secrete their products, hormones, directly into the blood rather than through a duct. (pituitary gland, pancreas, ovaries, testes, thyroid gland, and adrenal gland) The next region deep to the capsule is the adrenal cortex (2-4), which itself is subdivided into 3 zones: The first (outermost) layer of the cortex is the zona glomerulosa (2). It is fairly thin, and there are noticable spaces between the small clusters of cells. Next is the zona fasiculata (3).
No, the adrenal glands have a rich nerve supply.