adrenal medulla


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Related to adrenal medulla: adrenal cortex

medulla

 [mĕ-dul´ah] (L.)
1. the inmost part of a structure or organ.
3. marrow. adj., adj med´ullary.
adrenal medulla the inner portion of the adrenal gland, where epinephrine and norepinephrine are produced.
medulla of bone bone marrow.
medulla oblonga´ta that part of the hindbrain continuous with the pons above and the spinal cord below; it houses nerve centers for both motor and sensory nerves, where such functions as breathing and the beating of the heart are controlled. See also brain.
medulla os´sium bone marrow.
renal medulla the inner part of the substance of the kidney, composed chiefly of collecting tubules, and organized into a group of structures called the renal pyramids.
medulla spina´lis (medulla spina´lis) spinal cord.
medulla of thymus the central portion of each lobule of the thymus; it contains many more reticular cells and far fewer lymphocytes than does the surrounding cortex.

adrenal medulla

n.
The inner, reddish-brown portion of the adrenal glands that synthesizes, stores, and releases epinephrine and norepinephrine.

adrenal medulla

the inner portion of the adrenal gland. Its cells secrete the catecholamines epinephrine and norepinephrine when stimulated by the sympathetic division of the autonomic nervous system. Compare adrenal cortex.

Adrenal Medulla

The centre of the adrenal gland, which is a neuroendocrine “organ” which produces catecholamines (epinephrine/adrenaline & norepinephrine/ noradrenaline) in response to stress signals from the peripheral nervous system.
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ADRENAL MEDULLA

adrenal medulla

The central tissue of the adrenal gland. It is filled with pheochromocytes, which are derived from the neural crest and resemble postsynaptic sympathetic ganglion cells. In response to stimulation by presynaptic sympathetic axons, the pheochromocytes secrete epinephrine and norepinephrine into the bloodstream. See: illustration
See: adrenal gland
See also: medulla

adrenal medulla

The inner part of the ADRENAL GLAND that secretes the hormones ADRENALINE and noradrenaline. The secreting cells are called chromaffin cells. See also ADRENAL CORTEX.

Adrenal medulla

The inner part of the adrenal gland. The adrenal medulla produces the hormones epinephrine (adrenaline), which stimulates the heart, tightens blood vessels, and relaxes some smooth muscles; and norepinephrine, which has similar effects.

adrenal

1. near the kidney.
2. of or produced by the adrenal glands.
3. an adrenal gland.

adrenal cortex
the outer part of the adrenal gland made up of an external zona glomerulosa, a deeper zona fasciculata and a zona reticularis. It produces three main groups of hormones, the glucocorticoids which are concerned with increasing blood glucose levels, the mineralocorticoids concerned with the maintenance of electrolyte levels in the extracellular fluid, and androgens which have the same masculinizing effect as the hormone testosterone produced by the testis. Called also adrenal gland cortex. See glucocorticoid, mineralocorticoid, androgen.
adrenal cortex inhibitors
adrenal-cortical
adrenal cortical dysfunction
adrenal function tests
see acth response test, dexamethasone suppression test, v-test.
adrenal hyperplasia-like syndrome
a congenital abnormality of adrenal steroidogenesis reported in dogs which results in hyperprogestinism and hyperandrogenism. Clinical signs include bilaterally symmetrical alopecia resembling that seen with other endocrinopathies.
adrenal insufficiency
hypofunction of the adrenal gland, particularly the cortex, leading to signs of weakness and loss of sodium, chloride and water. See also primary hypoadrenocorticism.
adrenal medulla
a glandular extension of the effector fibers of the sympathetic nervous system that releases into the bloodstream the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline). When the sympathetic nervous system is stimulated the adrenal medulla responds also and its hormones are carried via the bloodstream to cause increases in cardiac output and metabolic rate, vasoconstriction and reduction of gastrointestinal peristalsis. The hormones have similar functions but epinephrine is removed from the bloodstream more slowly and has a more prolonged effect. Called also adrenal gland medulla.
Adrenal medullary hormones are not essential to life. Hypersecretion, such as occurs in some functional pheochromocytomas, causes tachycardia, edema and cardiac hypertrophy.
adrenal steroids
cortisol, corticosterone, cortisone, 11-dehydroxycortisone, desoxycorticosterone, 17-hydroxy-11-desoxycorticosterone, aldosterone, the adrenal corticoids from the adrenal cortex. Called also corticosteroids.

medulla

pl. medullae [L.] the central or inner portion of an organ.

adrenal medulla
the inner portion of the adrenal gland, where epinephrine is produced.
medulla of bone
bone marrow, contained in the medullary canal of bone.
medulla oblongata
that part of the hindbrain continuous with the pons anteriorly and the spinal cord posteriorly; it houses nerve centers for both motor and sensory nerves, where such functions as breathing and the beating of the heart are controlled. Called also myelencephalon. In animals the principal clinical manifestations of local lesions in the medulla are those of head rotation and circling, and facial and tongue paralysis with resulting difficulty in prehension and swallowing. With diffuse lesions spastic paralysis or a stiff-legged incoordination occurs.
medulla ossium
bone marrow.
renal medulla
the inner part of the substance of the kidney, composed chiefly of collecting tubules, and in some species organized into a group of structures called the renal pyramids.
spinal medulla, medulla spinalis
spinal cord.
medulla of thymus
the central portion of each lobule of the thymus; it contains many more reticular cells and far fewer lymphocytes than does the surrounding cortex.
References in periodicals archive ?
This input to the adrenal medulla may explain why core body exercises are so helpful in modulating responses to stress.
Hypertrophied adrenal medulla and higher capacity to secrete catecholamine in the endurance trained subject (22), can meet the need for higher A concentration at the same relative work load.
The adrenal medulla and extra-adrenal paraganglia: then and now.
One can hypothesize that adrenal medulla is so complex only in mammals, and may raise questions regarding its role in adaptation and survival.
Examples of these hormones, which are made in the adrenal medulla and the thyroid gland, are epinephrine, norepinephrine, and the thyroid hormones [T.
PCCs are rare catecholamine-producing tumours thought to arise from chromaffin cells in the adrenal medulla.
Intraabdominal paragangliomas are most commonly phaeochromocytomas of the adrenal medulla, while extraadrenal paragangliomas can arise in diverse locations.
Most sympathetic paraganglioma form within adrenal medulla, the main sympathetic paraganglia--these are commonly known as pheochromocytoma (PHEO).
The adrenal medulla secretes the "fight or flight" hormones: adrenaline (also called epinephrine) and noradrenaline (also called norepinephrine).
Microscopic evaluation revealed a benign tumor, composed of spindle cells with Schwann differentiation and ganglion cells with diffuse distribution, arising from the adrenal medulla and separated from the cortex with smooth margins without any capsule.
Approximately 85% arise from chromaffin cells in the adrenal medulla, and 15% arise from chromaffin tissue in extra-adrenal sites extending from the neck to the pelvis, although most are found intra-abdominally.
The decline of this ratio's normal value parallels de cline of the health and efficiency of the adrenal medulla, and becomes a significant threat to the health and well-being of the patient.

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