Exocrine gland
72672
222018429
2008-06-27T04:37:31Z
202.164.158.188
/* Types */
{{Refimprove|date=September 2007}}
{{Expand|article|date=March 2007}}
{{Cleanup|date=March 2007}}
{{Infobox Anatomy |
Name = Exocrine gland |
Latin = |
GraySubject = |
GrayPage = |
Image = Gray1026.png |
Caption = Human submaxillary gland. At the right is a group of mucous alveoli, at the left a group of serous alveoli.|
Image2 = |
Caption2 = |
System = |
MeshName = |
MeshNumber = |
DorlandsPre = |
DorlandsSuf = |
}}
'''Exocrine glands''' are [[gland]]s that secrete their products ([[enzyme]]s) into [[duct (anatomy)|duct]]s (duct glands). They are the counterparts to [[endocrine glands]], which secrete their products ([[hormone]]s) directly into the [[blood]]stream (ductless glands) or release hormones ([[paracrine]]s) affect only target cell nearby the release site.
==Examples==
Typical exocrine glands include [[sweat gland]]s, [[salivary gland]]s, [[mammary gland]]s, [[stomach]], [[liver]] and the [[pancreas]]. (Example of an endocrine gland is the adrenal gland, which is found on top of the kidneys and secretes the hormone adrenaline).
==Types==
There are many ways of classifying exocrine glands:
===Structure===
Exocrine glands contain a glandular portion and a duct portion, the structures of which can be used to classify the gland.
* The duct portion may be branched (called ''compound'') or unbranched (called ''simple'').
* The glandular portion may be tubular, [[acinus|acinar]], or may be a mix of the two (called tubuloacinar). If the glandular portion branches, then the gland is called a branched gland.
===Method of secretion===
Exocrine glands are named [[apocrine]] gland, [[holocrine]] gland, or [[merocrine]] gland based on how their product is secreted.
*'''Apocrine glands''' - a portion of the plasma membrane buds off the cell, containing the secretion. ''Apocrine gland'' is often used to refer to the [[apocrine sweat glands]] which use merocrine secretion.
*'''Holocrine glands''' - the entire cell disintegrates to secrete its substance.
*'''Merocrine glands''' - cells secrete their substances by [[exocytosis]]. Also called "eccrine."
===Product secreted===
* Serous cells secrete [[protein]]s, often [[enzyme]]s. Examples include [[chief cells]] and [[Paneth cells]]
* Mucous cells secrete [[mucus]]. Examples include [[Brunner's glands]], [[esophageal glands]], and [[pyloric glands]]
* Mixed glands secrete both protein and mucus. Examples include the [[salivary glands]], although [[parotid gland]] is predominantly serous, the [[sublingual gland]] is predominantly mucous and the submandibular gland is both serous and mucous.
==List of exocrine glands==
Glands typically may be referred to by two or more means, though some terms are rarely seen. The names of the [[anatomist]]s who first described them are often employed, as:
{| class="sortable wikitable"
| '''name(s)''' || '''location''' || '''product''' || '''structure'''
|-
| [[apocrine sweat glands]] || [[skin]] || - || coiled tubular
|-
| [[Bartholin's glands]], Tiedmann's glands, vulvovaginal glands || [[vulva]], [[vagina]] || - || -
|-
| [[anterior lingual glands|Bauhin's glands]], anterior lingual glands || [[tongue]], near tip || nonserous or mixed || -
|-
| [[Brunner's glands]], duodenal glands || [[duodenum]] || mucous || compound tubular
|-
| [[bulbourethral glands]], Cowper's glands, Mery's glands || [[penis]], base || - || -
|-
| [[Ciaccio's glands]], accessory [[lacrimal glands]] || [[eye]] || - || -
|-
| [[Cobelli's glands]] || [[esophagus]], just above the [[cardia]], in the [[mucosa]] || mucous || -
|-
| [[Duverney's gland]] || [[vagina]], on either side || - || -
|-
| [[Ebner's glands]] || [[tongue]] || serous || -
|-
| [[eccrine sweat glands]] || [[skin]] || - || coiled tubular
|-
| [[esophageal glands]] || [[esophagus]] || mucous || racemose
|-
| [[exocrine pancreas]] || [[pancreas]] || serous || tubulo-acinar
|-
| [[Fränkel's glands]] || [[vocal cords]], below the edge || - || -
|-
| [[gastric chief cell]], Wasmann's glands || [[stomach]] || serous || -
|-
| [[glomus coccygeum]], coccygeal gland, Luschka's gland or ganglion || [[coccyx]], near the tip || - || -
|-
| [[goblet cells]] || [[digestive tract]], [[respiratory tract]] || mucous || simple unicellular
|-
| [[Crypts of Henle|Henle's glands]] || [[eyelids]], in the [[conjuctiva]] || - || tubular
|-
| [[Huguier's glands]] || [[vagina]] || - || -
|-
| [[Krause's glands]] || [[conjunctiva]], middle portion || mucous || -
|-
| [[Lieberkuhn's gland]]s || [[intestines]], surface of [[mucous membrane]] || - || simple tubular
|-
| [[Littré's glands]], Morgagni's glands || [[spongy portion of the urethra]] || - || [[racemose]]
|-
| [[mammary gland]] || [[breast]] || - || compound tubulo-acinar
|-
| [[Meibomian gland]] || [[eyelids]] || sebaceous || -
|-
| [[Glands of Moll|Moll's glands]] || [[eyelids]] || - || -
|-
| [[Montgomery's glands]] || mammary [[areola]] || sebaceous || -
|-
| [[Naboth's glands]] || [[cervix]] and [[os uteri]] || mucous || -
|-
| [[olfactory glands]], Bowman's glands || [[nose]], [[olfactory]] region || - || -
|-
| [[Paneth cells]] || [[small intestine]] || serous || -
|-
| [[parathyroid glands]], Gley's glands, Sandstroem's glands || [[thyroid]], on surface || - || -
|-
| [[parotid gland]] || [[mouth]] || serous || tubulo-alveolar
|-
| [[Peyer's patches]] (or glands) || [[ileum]], [[lymphatic]] glands || - || -
|-
| [[pyloric glands]] || [[stomach]] || mucous || simple branched tubular
|-
| [[sebaceous gland]] || [[skin]] || sebum || acinar - branched
|-
| [[Skene's glands]], Guérin's glands || [[vagina]] || - || -
|-
| [[sublingual gland]], Rivini's gland || [[mouth]] || mucus (primarily) || tubulo-alveolar
|-
| [[submandibular gland]] || [[mouth]] || mixed (M+S) || tubulo-alveolar
|-
| [[sudoriparous glands]], Boerhaave's glands || [[skin]] || - || -
|-
| [[Sigmund's glands]] || [[epitrochlear]] [[lymph node]]s || - || -
|-
| [[Suzanne's gland]] || mouth, beneath the [[alveolingual]] groove || mucous || -
|-
| [[Weber's glands]] || [[tongue]] || mucous || tubular
|-
| [[Glands of Zeis]] || [[eyelids]], free edges || sebaceous || -
|}
==See also==
* [[Wikipedia:MeSH A10#MeSH A10.336 --- exocrine glands]]
Prostate gland is an exocrine gland of the male mammalian reproductive system. It secretes a clear and basic fluid that constitutes 1/3 of the volume of semen.
==Additional images==
<gallery>
Image:Gray1033.png|Section of the human esophagus. Moderately magnified.
Image:Gray1172.png|Dissection of a lactating breast.
</gallery>
==References==
{{reflist}}
==External links==
* [http://www.mhhe.com/biosci/ap/histology_mh/glands.html Diagram at mhhe.com]
* {{eMedicineDictionary|gland}}
{{Glands}}
[[Category:Glands]]
[[Category:Integumentary system]]
[[ar:غدة قنوية]]
[[de:Exokrine Drüse]]
[[es:Glándula exocrina]]
[[fr:Glande exocrine]]
[[is:Útkirtietethhethetll]]
[[he:בלוטה אקסוקרינית]]
[[ja:外分泌腺]]
[[pt:Glândula exócrina]]
[[ru:Железа внешней секреции]]
[[sl:Žleza z zunanjim izločanjem]]