adrenal medulla

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Related to adrenal medulla: adrenal cortex


 [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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

adrenal medulla

The inner, reddish-brown portion of the adrenal glands that synthesizes, stores, and releases epinephrine and norepinephrine.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

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.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
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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
Medical Dictionary, © 2009 Farlex and Partners

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.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

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.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Other investigators had suspected that one or, perhaps, two cortical areas might be responsible for the control of the adrenal medulla. The actual number and location of the cortical areas were uncertain.
Pheochromocytomas are tumors of the adrenal medulla that produce and usually secrete large amounts of catecholamines often associated with high fatality rates when undiagnosed (1).
In spite of many advances taking place in the evaluation of tumours of adrenal medulla, careful gross examination and histological interpretation of H and E sections still remain the fulcrum basing on which an accurate diagnosis is made.
Studies using these methods, have reported that hypertrophied adrenal medulla in trained subjects corresponds to a higher capacity to secrete catecholamine in response to exercise (1).
In the adrenal medulla, norepinephrine is converted to epinephrine in the presence of phenylethanolamine-N-methyltransferase.
The sites of origin of ganglioneuroblastoma include adrenal medulla, extra-adrenal retroperitoneum, posterior mediastinum, the neck, and pelvis.
Pheochromocytoma (PHEO), although rare, is a tumor of the chromaffin tissue with 90% localization in the adrenal medulla. It causes an excessive secretion of catecholamines that leads to symptoms such as headaches, excessive sweating, flushing or anxiety as well as cardiovascular signs--palpitations, tachycardia or paroxysmal arterial hypertension [1].
In contrast, it mostly arises from VIP secreting tumor originating from the neural crest cells in the adrenal medulla or sympathetic ganglia in children (4).
Kmiec, "Histological and histochemical studies on the regeneration of the adrenal medulla after its enucleation in white rats," Folia Morphologica, vol.
Phaeochromocytomas are neuro-endocrine catecholamine-secreting tumours that arise from chromaffin cells of the adrenal medulla or sympathetic paraganglia.

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