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The endocrine system is a group of glands that work together and secrete many types of different hormones that regulate the body.
The endocrine system is a group of glands that work together and secrete many types of different hormones that regulate the body.
The field of study that deals with disorders of endocrine glands is endocrinology, a branch of the wider field of internal medicine.
The field of study that deals with disorders of endocrine glands is endocrinology, a branch of the wider field of internal medicine.
yuhj serorega
==Function==
The endocrine system is an information signal system much like the [[nervous system]]. Hormones regulate many functions of an organism, including [[Mood (psychology)|mood]], [[human development (biology)|growth and development]], [[tissue (biology)|tissue function]], and [[metabolism]].

===Types of signaling=== <!--Cell signaling has a redirection to here-->
The typical mode of [[cell signaling]] in the endocrine system is [[endocrine signaling]]. However, there are also other modes, i.e., paracrine, autocrine, and [[neuroendocrine]] signaling.<ref>[http://www.med-ed.virginia.edu/public/CourseSitesDocs/CellandTissueStructure/handouts/unrestricted/original/MMHndt_Endocrine.htmhttp://www.youtube.com/watch?v=AmRZnRp8_B8l University of Virginia - HISTOLOGY OF THE ENDOCRINE GLANDS]</ref> Purely neurocrine signaling between [[neurons]], on the other hand, belongs completely to the [[nervous system]].

====Endocrine====
{{Main|Endocrine signalling}} The endocrine system is made up of a series of [[ductless gland]]s that produce chemical messages called hormones
A number of glands that signal each other in sequence is usually referred to as an axis, for example, the [[hypothalamic-pituitary-adrenal axis]].
Typical endocrine glands are the [[pituitary]], [[thyroid]], and [[adrenal]] glands. Features of endocrine glands are, in general, their ductless nature, their vascularity, and usually the presence of intracellular vacuoles or granules storing their hormones. In contrast, [[exocrine gland]]s, such as [[salivary gland]]s, [[sweat gland]]s, and [[glands]] within the [[gastrointestinal tract]], tend to be much less vascular and have ducts or a hollow [[Lumen (anatomy)|lumen]]. Also controls metabolism in our body system.

====Autocrine====
{{Main|Autocrine signalling}}
Other signaling can target the same cell, or other cells.{{Citation needed|date=October 2009}}
{{Expand section|date=October 2009}}

====Paracrine====
{{Main|Paracrine signalling}}
Paracrine signaling is where the target cell is nearby.{{Citation needed|date=October 2009}}
{{Expand section|date=October 2009}}

====Juxtacrine====
Juxtacrine signalling
Juxtacrine signals are transmitted along cell membranes via protein or lipid components integral to the membrane and are capable of affecting either the emitting cell or cells immediately adjacent.{{Citation needed|date=October 2009}}
{{Expand section|date=October 2009}}

{{Main|Endocrine diseases}}
[[Endocrine diseases|Diseases of the endocrine system]] are common,<ref>{{cite book
| last = Kasper ''et al.''
| title = Harrison's Principles of Internal Medicine
| publisher = [[McGraw Hill]]
| year = 2005
| pages = 2074
| isbn =0-07-139140-1 }}</ref> including conditions such as [[diabetes mellitus]], [[thyroid]] disease, and [[obesity]].
Endocrine disease is characterized by dysregulated hormone release (a productive [[pituitary adenoma]]), inappropriate response to signaling ([[hypothyroidism]]), lack of a gland ([[diabetes mellitus type 1]], diminished [[erythropoiesis]] in [[chronic renal failure]]), or structural enlargement in a critical site such as the testis ([[toxic multinodular goitre]]). Hypofunction of endocrine glands can occur as a result of loss of reserve, hyposecretion, [[agenesis]], atrophy, or active destruction. Hyperfunction can occur as a result of hypersecretion, loss of suppression, [[hyperplasia|hyperplastic]] or [[neoplastic]] change, or hyperstimulation.

Endocrinopathies are classified as primary, secondary, or tertiary. Primary endocrine disease inhibits the action of downstream glands. Secondary endocrine disease is indicative of a problem with the pituitary gland. Tertiary endocrine disease is associated with dysfunction of the hypothalamus and its releasing hormones.{{Citation needed|date=October 2009}}

As the [[Thyroid cancer|thyroid]], and hormones have been implicated in signaling distant tissues to proliferate, for example, the [[estrogen receptor]] has been shown to be involved in certain [[breast cancer]]s. Endocrine, paracrine, and autocrine signaling have all been implicated in proliferation, one of the required steps of [[oncogenesis]].<ref>{{cite journal |author=Bhowmick NA, Chytil A, Plieth D, ''et al.'' |title=TGF-beta signaling in fibroblasts modulates the oncogenic potential of adjacent epithelia |journal=Science |volume=303 |issue=5659 |pages=848–51 |year=2004 |month=February |pmid=14764882 |doi=10.1126/science.1090922 }}</ref>


==Table of endocrine glands and secreted hormones==
==Table of endocrine glands and secreted hormones==

Revision as of 14:20, 23 November 2009

Major endocrine glands. (Male on the left, female on the right.) 1. Pineal gland 2. Pituitary gland 3. Thyroid gland 4. Thymus 5. Adrenal gland 6. Pancreas 7. Ovary 8. Testes

The endocrine system is a group of glands that work together and secrete many types of different hormones that regulate the body. The field of study that deals with disorders of endocrine glands is endocrinology, a branch of the wider field of internal medicine. yuhj serorega

Table of endocrine glands and secreted hormones

This is a table of the glands of the endocrine system, and their secreted hormones.

Hypothalamus

Secreted hormone Abbreviation Produced by Effect
Thyrotropin-releasing hormone
(Prolactin-releasing hormone) 		TRH, TRF, or PRH Parvocellular neurosecretory neurons Stimulate thyroid-stimulating hormone (TSH) release from anterior pituitary (primarily)
Stimulate prolactin release from anterior pituitary
Dopamine
(Prolactin-inhibiting hormone) 		DA or PIH Dopamine neurons of the arcuate nucleus Inhibit prolactin release from anterior pituitary
Growth hormone-releasing hormone GHRH Neuroendocrine neurons of the Arcuate nucleus Stimulate Growth hormone (GH) release from anterior pituitary
Somatostatin
(growth hormone-inhibiting hormone) 		SS, GHIH, or SRIF Neuroendocrine cells of the Periventricular nucleus Inhibit Growth hormone (GH) release from anterior pituitary
Inhibit thyroid-stimulating hormone (TSH) release from anterior pituitary
Gonadotropin-releasing hormone GnRH or LHRH Neuroendocrine cells of the Preoptic area Stimulate follicle-stimulating hormone (FSH) release from anterior pituitary
Stimulate luteinizing hormone (LH) release from anterior pituitary
Corticotropin-releasing hormone CRH or CRF Parvocellular neurosecretory neurons Stimulate adrenocorticotropic hormone (ACTH) release from anterior pituitary
Oxytocin Magnocellular neurosecretory cells Uterine contraction
Lactation (letdown reflex)
Vasopressin
(antidiuretic hormone) 		ADH or AVP Parvocellular neurosecretory neurons Increases water permeability in the distal convoluted tubule and collecting duct of nephrons, thus promoting water reabsorption and increasing blood volume

Pineal body (epiphysis)

Secreted hormone From cells Effect
Melatonin (Primarily) Pinealocytes Antioxidant
Monitors the circadian rhythm including inducement of drowsiness
Dimethyltryptamine Speculated role in mystical and dream experiences

Pituitary Gland (hypophysis)

Anterior pituitary lobe (adenohypophysis)

Secreted hormone Abbreviation From cells Effect
Growth hormone
(somatotropin) 		GH Somatotropes Stimulates growth and cell reproduction
Stimulates Insulin-like growth factor 1 release from liver
Thyroid-stimulating hormone
(thyrotropin) 		TSH Thyrotropes Stimulates thyroxine (T4) and triiodothyronine (T3) synthesis and release from thyroid gland
Stimulates iodine absorption by thyroid gland
Adrenocorticotropic hormone
(corticotropin) 		ACTH Corticotropes Stimulates corticosteroid (glucocorticoid and mineralcorticoid) and androgen synthesis and release from adrenocortical cells
Follicle-stimulating hormone FSH Gonadotropes In females: Stimulates maturation of ovarian follicles in ovary
In males: Stimulates maturation of seminiferous tubules
In males: Stimulates spermatogenesis
In males: Stimulates production of androgen-binding protein from Sertoli cells of the testes
Luteinizing hormone LH Gonadotropes In females: Stimulates ovulation
In females: Stimulates formation of corpus luteum
In males: Stimulates testosterone synthesis from Leydig cells (interstitial cells)
Prolactin PRL Lactotropes Stimulates milk synthesis and release from mammary glands
Mediates sexual gratification

Posterior pituitary lobe (neurohypophysis)

Secreted hormone Abbreviation From cells Effect
Oxytocin Magnocellular neurosecretory cells Uterine contraction
Lactation (letdown reflex)
Vasopressin
(antidiuretic hormone) 		ADH or AVP Parvocellular neurosecretory neurons Increases water permeability in the distal convoluted tubule and collecting duct of nephrons, thus promoting water reabsorption and increasing blood volume

Oxytocin and anti-diuretic hormone are not secreted in the posterior lobe, merely stored.

Intermediate pituitary lobe (pars intermedia)

Secreted hormone Abbreviation From cells Effect
Melanocyte-stimulating hormone MSH Melanotropes Stimulates melanin synthesis and release from skin/hair melanocytes

Thyroid

Secreted hormone Abbreviation From cells Effect
Triiodothyronine T3 Thyroid epithelial cell (More potent form of thyroid hormone)
Stimulates body oxygen and energy consumption, thereby increasing the basal metabolic rate
Stimulates RNA polymerase I and II, thereby promoting protein synthesis
Thyroxine
(tetraiodothyronine) 		T4 Thyroid epithelial cells (Less active form of thyroid hormone)
(Acts as a prohormone to triiodothyronine)
Stimulates body oxygen and energy consumption, thereby increasing the basal metabolic rate
Stimulates RNA polymerase I and II, thereby promoting protein synthesis
Calcitonin Parafollicular cells Stimulates osteoblasts and thus bone construction
Inhibits Ca2+ release from bone, thereby reducing blood Ca2+

Parathyroid

Secreted hormone Abbreviation From cells Effect
Parathyroid hormone PTH Parathyroid chief cell Calcium:
  • Stimulates Ca2+ release from bone, thereby increasing blood Ca2+
  • Stimulates osteoclasts, thus breaking down bone
  • Stimulates Ca2+ reabsorption in kidney
  • Stimulates activated vitamin D production in kidney


Phosphate:

  • Stimulates PO4= release from bones, thereby increasing blood PO4=
  • Inhibits PO4= reabsorption in kidney, so more PO4= is excreted
  • Overall, small net drop in serum PO4=

Heart

Secreted hormone Abbreviation From cells Effect
Atrial-natriuretic peptide ANP Cardiac myocytes Reduce blood pressure by:

reducing systemic vascular resistance, reducing blood water, sodium and fats

Brain natriuretic peptide BNP Cardiac myocytes (To a lesser degree than ANP) reduce blood pressure by:

reducing systemic vascular resistance, reducing blood water, sodium and fats

Striated muscle

Secreted hormone From cells Effect
Thrombopoietin Myocytes stimulates megakaryocytes to produce platelets[1]

Skin

Secreted hormone From cells Effect
Calcidiol (25-hydroxyvitamin D3) Inactive form of Vitamin D3

Adipose tissue

Secreted hormone From cells Effect
Leptin (Primarily) Adipocytes decrease of appetite and increase of metabolism.
Estrogens[2] (mainly Estrone) Adipocytes

Stomach

Secreted hormone Abbreviation From cells Effect
Gastrin (Primarily) G cells Secretion of gastric acid by parietal cells
Ghrelin P/D1 cells Stimulate appetite,

secretion of growth hormone from anterior pituitary gland

Neuropeptide Y NPY increased food intake and decreased physical activity
Somatostatin D cells Suppress release of gastrin, cholecystokinin (CCK), secretin, motilin, vasoactive intestinal peptide (VIP), gastric inhibitory polypeptide (GIP), enteroglucagon

Lowers rate of gastric emptying Reduces smooth muscle contractions and blood flow within the intestine.[3]

Histamine ECL cells stimulate gastric acid secretion
Endothelin X cells Smooth muscle contraction of stomach[4]

Duodenum

Secreted hormone From cells Effect
Secretin S cells Secretion of bicarbonate from liver, pancreas and duodenal Brunner's glands

Enhances effects of cholecystokinin Stops production of gastric juice

Cholecystokinin I cells Release of digestive enzymes from pancreas

Release of bile from gallbladder hunger suppressant

Liver

Secreted hormone Abbreviation From cells Effect
Insulin-like growth factor (or somatomedin) (Primarily) IGF Hepatocytes insulin-like effects

regulate cell growth and development

Angiotensinogen and angiotensin Hepatocytes vasoconstriction

release of aldosterone from adrenal cortex dipsogen.

Thrombopoietin Hepatocytes stimulates megakaryocytes to produce platelets[1]

Pancreas

Secreted hormone From cells Effect
Insulin (Primarily) β Islet cells Intake of glucose, glycogenesis and glycolysis in liver and muscle from blood

intake of lipids and synthesis of triglycerides in adipocytes Other anabolic effects

Glucagon (Also Primarily) α Islet cells glycogenolysis and gluconeogenesis in liver

increases blood glucose level

Somatostatin δ Islet cells Inhibit release of insulin[5]

Inhibit release of glucagon[5] Suppress the exocrine secretory action of pancreas.

Pancreatic polypeptide PP cells Unknown

Kidney

Secreted hormone From cells Effect
Renin (Primarily) Juxtaglomerular cells Activates the renin-angiotensin system by producing angiotensin I of angiotensinogen
Erythropoietin (EPO) Extraglomerular mesangial cells Stimulate erythrocyte production
Calcitriol (1,25-dihydroxyvitamin D3) Active form of vitamin D3

Increase absorption of calcium and phosphate from gastrointestinal tract and kidneys inhibit release of PTH

Thrombopoietin stimulates megakaryocytes to produce platelets[1]

Adrenal glands

Adrenal cortex

Secreted hormone From cells Effect
Glucocorticoids (chiefly cortisol) zona fasciculata and zona reticularis cells Stimulates gluconeogenesis
Stimulates fat breakdown in adipose tissue
Inhibits protein synthesis
Inhibits glucose uptake in muscle and adipose tissue
Inhibits immunological responses (immunosuppressive)
Inhibits inflammatory responses (anti-inflammatory)
Mineralocorticoids (chiefly aldosterone) Zona glomerulosa cells Stimulates active sodium reabsorption in kidneys
Stimulates passive water reabsorption in kidneys, thus increasing blood volume and blood pressure
Stimulates potassium and H+ secretion into nephron of kidney and subsequent excretion
Androgens (including DHEA and testosterone) Zona fasciculata and Zona reticularis cells In males: Relatively small effect compared to androgens from testes
In females: masculinizing effects (ie. excessive facial hair)

Adrenal medulla

Secreted hormone From cells Effect
Adrenaline (epinephrine) (Primarily) Chromaffin cells Fight-or-flight response:
Noradrenaline (norepinephrine) Chromaffin cells Fight-or-flight response:
Dopamine Chromaffin cells Increase heart rate and blood pressure
Enkephalin Chromaffin cells Regulate pain

Testes

Secreted hormone From cells Effect
Androgens (chiefly testosterone) Leydig cells Anabolic: growth of muscle mass and strength, increased bone density, growth and strength,

Virilizing: maturation of sex organs, formation of scrotum, deepening of voice, growth of beard and axillary hair.

Estradiol Sertoli cells Prevent apoptosis of germ cells[6]
Inhibin Sertoli cells Inhibit production of FSH

Ovarian follicle / Corpus luteum

Secreted hormone From cells Effect
Progesterone Granulosa cells, theca cells Support pregnancy[7]:

Other:

Anti-inflammatory

Androstenedione Theca cells Substrate for estrogen
Estrogens (mainly estradiol) Granulosa cells Structural:

Protein synthesis:

  • Increase hepatic production of binding proteins

Coagulation:

Fluid balance:

Gastrointestinal tract:

  • Reduce bowel motility
  • Increase cholesterol in bile

Melanin:

Cancer:

Lung function:

Inhibin Granulosa cells Inhibit production of FSH from anterior pituitary

Placenta (when pregnant)

Secreted hormone Abbreviation From cells Effect
Progesterone (Primarily) Support pregnancy[7]:

Other effects on mother similar to ovarian follicle-progesterone

Estrogens (mainly Estriol) (Also Primarily) Effects on mother similar to ovarian follicle estrogen
Human chorionic gonadotropin HCG Syncytiotrophoblast promote maintenance of corpus luteum during beginning of pregnancy

Inhibit immune response, towards the human embryo.

Human placental lactogen HPL Syncytiotrophoblast increase production of insulin and IGF-1

increase insulin resistance and carbohydrate intolerance

Inhibin Fetal Trophoblasts suppress FSH

Uterus (when pregnant)

Secreted hormone Abbreviation From cells Effect
Prolactin PRL Decidual cells milk production in mammary glands
Relaxin Decidual cells Unclear in humans and animals

Diseases

Disability-adjusted life year for endocrine disorders per 100,000 inhabitants in 2002.[12]
  no data
  less than 80
  80-160
  160-240
  240-320
  320-400
  400-480
  480-560
  560-640
  640-720
  720-800
  800-1000
  more than 1000

See also

References

  1. ^ a b c Kaushansky K (2006). "Lineage-specific hematopoietic growth factors". N Engl J Med. 354 (19): 2034–45. doi:10.1056/NEJMra052706. PMID 16687716. {{cite journal}}: Unknown parameter |month= ignored (help)
  2. ^ Frühbeck G (2004). "The adipose tissue as a source of vasoactive factors". Curr Med Chem Cardiovasc Hematol Agents. 2 (3): 197–208. doi:10.2174/1568016043356255. PMID 15320786. {{cite journal}}: Unknown parameter |month= ignored (help)
  3. ^ Colorado State University - Biomedical Hypertextbooks - Somatostatin
  4. ^ Endo K, Matsumoto T, Kobayashi T, Kasuya Y, Kamata K (2005). "Diabetes-related changes in contractile responses of stomach fundus to endothelin-1 in streptozotocin-induced diabetic rats" ([dead link‍] – Scholar search). J Smooth Muscle Res. 41 (1): 35–47. doi:10.1540/jsmr.41.35. PMID 15855738. {{cite journal}}: External link in |format= (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  5. ^ a b Template:GeorgiaPhysiology
  6. ^ Pentikäinen V, Erkkilä K, Suomalainen L, Parvinen M, Dunkel L (2000). "Estradiol acts as a germ cell survival factor in the human testis in vitro". J Clin Endocrinol Metab. 85 (5): 2057–67. doi:10.1210/jc.85.5.2057. PMID 10843196. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  7. ^ a b c d Placental Hormones
  8. ^ Template:GeorgiaPhysiology
  9. ^ Hould F, Fried G, Fazekas A, Tremblay S, Mersereau W (1988). "Progesterone receptors regulate gallbladder motility". J Surg Res. 45 (6): 505–12. doi:10.1016/0022-4804(88)90137-0. PMID 3184927.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ^ Hormonal Therapy
  11. ^ Massaro D, Massaro GD (2004). "Estrogen regulates pulmonary alveolar formation, loss, and regeneration in mice". American Journal of Physiology. Lung Cellular and Molecular Physiology. 287 (6): L1154–9. doi:10.1152/ajplung.00228.2004. PMID 15298854.
  12. ^ "Mortality and Burden of Disease Estimates for WHO Member States in 2002" (xls). World Health Organization. 2002.



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