Adrenal glands


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adrenal glands

The small internally secreting (ENDOCRINE) organs which sit like triangular caps one on top of each KIDNEY (hence the name). Each adrenal has two distinct parts, the inner core, which produces ADRENALINE, and an outer layer (the cortex) which produces various steroid hormones. Formerly known as suprarenal glands, which, of course, means the same thing.

Adrenal glands

The two glands that are located on top of the kidneys. These glands secrete several hormones, including the glucocorticoids which, among other things, influence the way the immune system works, and the mineralocorticoids, which affect retention of water and sodium.

adrenal glands

endocrine glands sited above each kidney. The outermost region, the adrenal cortex, secretes steroid hormones: the glucocorticoids (principally cortisol), mineralocorticoids (principally aldosterone) and androgens in both male and female. The inner adrenal medulla secretes the catecholamines, mainly adrenaline and noradrenaline, under the control of the sympathetic nervous system. See also adrenocorticotrophic hormone (ACTH), hormones, steroids; Table 1.
Table 1: Hormones
Site of productionName of hormoneMain targetsInvolved in regulating:Secretion controlled by:
HypothalamusReleasing and inhibiting hormonesAnterior pituitary (via local blood vessels)Secretion of anterior pituitary hormonesOther brain regions; feedback re regulated hormones and their actions
Neurohormones released from posterior pituitary:
OxytocinUterus, breastsLabour and lactationAfferent information from target organs
Antidiuretic hormone (ADH, vasopressin)KidneysWater loss: ECF volume and osmolalityHypothalamic osmoreceptors
Anterior pituitary(Human) growth hormone (H)GHMost cellsGrowth and metabolismHypothalamic releasing and inhibiting hormones via local blood vessels
ProlactinBreastsMilk production
Trophic hormones:
Thyroid-stimulating (TSH)Thyroid glandThyroid secretions
GonadotrophinsOvary or testisGerm cell maturation and hormone secretions
Adrenocorticotrophic (ACTH)Adrenal cortexCortisol secretion
Pineal bodyMelatoninWidespread, including brain, thymus, etc.
  • Sleep/wake cycle
  • Antioxidant
  • Immune system
Hypothalamus; varying light input from retina
Thyroid
  • Thyroxine
  • Triiodothyronine
  • Calcitonin
  • Most cells
  • Bone, kidneys, gut
  • Cellular oxidative metabolism
  • Decreases ECF [Ca2+]
  • TSH from anterior pituitary. Negative feedback from blood hormone concentration
  • ECF [Ca2+]
ParathyroidsParathormoneBone, kidneys, gut
  • Calcium and phosphorus absorption, secretion and turnover in bone.
  • Increases ECF [Ca2+]
ECF [Ca2+]
Adrenal: Cortex
  • Cortisol
  • Aldosterone
  • Androgens
  • Most cells
  • Kidneys
  • Gonads & other tissues
  • Metabolism
  • Response to stress
  • Na and K balance
  • Sex characteristics and reproductive function
  • ACTH from anterior pituitary
  • ECF [Na+] [K+]
  • Renin-angiotensin
  • ACTH
Medulla
  • Adrenaline
  • Noradrenaline
Heart, smooth muscle, glandsCardiovascular and metabolic adjustments to activity and stressSympathetic nervous system
Atrial wallAtrial natriuretic hormoneKidneysBlood volume; increases sodium (therefore also water) loss in urineStretch of atrial wall by venous pressure
Gonads: TestisAndrogens (mainly testosterone)Genitalia and other tissuesReproductive function and sex characteristicsAnterior pituitary gonadotrophins
Ovary
  • Oestrogens
  • Progesterone
Uterus, breasts and other tissuesMenstrual cycle, pregnancy, lactation
Pancreas
  • Insulin, glucagon
  • Somatostatin
  • Most cells
  • Other secretory cells in the pancreas
Blood levels, storage and cellular uptake of nutrients, notably glucose, but also proteins and fatsBlood levels of nutrients; autonomic nervous system; other gastrointesinal hormones
Alimentary tract
StomachGastrinGastric acid-secreting cellsGastrointestinal functions: motility, digestive juices and other secretionsLocal chemical and mechanical factors in the alimentary tract
Small intestine
  • Secretin
  • Cholecystokinin- pancreozymin (CCK-PZ)
  • Somatostatin, motilin
  • Other peptide hormones including vasoactive intestinal peptide (VIP)
  • Widespread on
  • GI tract
Several GI functions including bile flow, pancreatic enzyme and exocrine secretionsIngestion of food, distension of GI tract
References in periodicals archive ?
Don't wait until your adrenal glands can no longer recover.
For purposes of differential diagnosis, masses of the adrenal gland are commonly grouped into those that are fat containing, cystic, hypervascular and overtly malignant.
Eighteen adrenal glands (right n=9 and left n=9) were used from nine healthy SYT cavies (five no pregnant females and four males) adults (from 6 to 12 months old), prevenient of the Center for Wild Animals Multiplication at Federal Rural University of the Semi-Arid, in the Mossoro RN Brazil.
The aim of our study was to investigate the differences in adrenal volume between nondiabetic controls and Type-2 diabetic patients and to examine the influence of glycemic control in diabetes mellitus on adrenal gland volume.
Despite the fact that the adrenal gland cortex has considerable capacity for regeneration, and effective anti-TB therapy may lead to some recovery of hormonal, adrenal function, patients usually have to remain on hormone replacement therapy.
The adrenal gland derives its name due to its proximity and situation atop the kidneys specifically on their anterosuperior aspect.
In 1982, to understand more clearly steroidogenesis in the adrenal cortex, we attempted to localize CYP11A1 and CYP11B1 immunohistochemically in bovine adrenal glands.
The thyroid and adrenal glands work in conjunction to manage energy in the body, so supporting the thyroid gland always supports the adrenal glands indirectly (note: taking thyroid hormone without proper adrenal function can burn out the adrenal gland to an even greater extent, as thyroid hormone increases the degradation of adrenal hormones through detoxification pathway--which may answer why some patients feel even worse on thyroid medication).
One of the best ways to support your adrenal glands is learning how to effectively deal with stress through relaxation techniques and exercise.
The abnormal tissue in the tumour produces an excess of hormone, which prompts the adrenal glands to produce extra cortisol, resulting in a huge excess.
Sitting near (or ad, in Latin) the kidneys (renes), the adrenal glands are neither small nor tidy.
OVERCOMING ADRENAL FATIGUE: HOW TO RESTORE HORMONAL BALANCE AND FEEL RENEWED, ENERGIZED, AND STRESS FREE offers self-help collections a fine guide to finding relief from chronic fatigue, allergies, poor digestion and more symptoms of adrenal fatigue, discussing the key role the adrenal glands play in controlling stress and maintaining energy.

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