adrenal medulla(redirected from Medullary portion)
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Related to Medullary portion: medullary pyramid
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.
The inner, reddish-brown portion of the adrenal glands that synthesizes, stores, and releases epinephrine and norepinephrine.
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 MedullaThe 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.
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: illustrationSee: adrenal gland
See also: medulla
adrenal medullaThe inner part of the ADRENAL GLAND that secretes the hormones ADRENALINE and noradrenaline. The secreting cells are called chromaffin cells. See also ADRENAL CORTEX.
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.
1. near the kidney.
2. of or produced by the adrenal glands.
3. an adrenal gland.
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 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.
hypofunction of the adrenal gland, particularly the cortex, leading to signs of weakness and loss of sodium, chloride and water. See also primary hypoadrenocorticism.
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.
cortisol, corticosterone, cortisone, 11-dehydroxycortisone, desoxycorticosterone, 17-hydroxy-11-desoxycorticosterone, aldosterone, the adrenal corticoids from the adrenal cortex. Called also corticosteroids.
pl. medullae [L.] the central or inner portion of an organ.
the inner portion of the adrenal gland, where epinephrine is produced.
medulla of bone
bone marrow, contained in the medullary canal of bone.
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.
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
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.