View source for Acinus

{{Short description|Multi-lobed biological cell structure}}
{{For|the acinus in the lung|Lung#Respiratory zone}}

{{Infobox anatomy
| Name        = Acinus
| Latin       =
| Image       = Normal breast histology.png
| Caption     = Normal histology of the breast, including an acinus in lower image. The terminal duct connected to the magnified acinus is not within this [[microsection]].
| Image2      = Centroacinar cells.jpg
| Caption2    = Centroacinar cells
| System      =
}}

An '''acinus''' ({{IPAc-en|ˈ|æ|s|ᵻ|n|ə|s}}; {{plural form}}: '''acini'''; adjective, '''acinar''' {{IPAc-en|ˈ|æ|s|ᵻ|n|ər}} or '''acinous''') refers to any cluster of [[cell (biology)|cells]] that resembles a many-lobed "[[Berry-like|berry]]", such as a [[raspberry]] (''[[wikt:acinus#Latin|acinus]]'' is [[Latin]] for "berry"). The berry-shaped termination of an [[exocrine gland]], where the secretion is produced, is acinar in form, as is the alveolar sac containing multiple [[Pulmonary alveolus|alveoli]] in the [[lungs]].

==Exocrine glands==
Acinar exocrine glands are found in many organs, including:
* the [[stomach]]<ref>{{OklahomaHistology|51_07}} - [[pyloric stomach]]</ref>
* the [[sebaceous gland]] of the [[scalp]]
* the [[salivary glands]] of the [[tongue]]<ref>{{OklahomaHistology|46_03}} - [[sublingual gland]]</ref>
* the [[liver]]
* the [[lacrimal glands]]
* the [[mammary glands]]
* the [[pancreas]]<ref>{{BUHistology|10405loa|inline=1}}</ref>
* the [[bulbourethral gland|bulbourethral (Cowper's) glands]]
The [[thyroid]] [[Thyroid#Histology|follicles]] can also be considered of acinar formation but in this case the follicles, being part of an ''endocrine'' gland, act as a hormonal deposit rather than to facilitate secretion.<br>
Mucous acini usually stain pale, while serous acini usually stain dark.<br>

==Lungs==
The end of the [[terminal bronchioles]] in the [[lungs]] mark the beginning of a [[pulmonary acinus]] that includes the [[respiratory bronchioles]],  alveolar ducts, alveolar sacs, and [[Pulmonary alveolus|alveoli]].<ref>{{Cite book|title=Principles of Pulmonary Medicine| vauthors = Weinberger S |publisher=Elsevier |year=2019 |isbn=978-0-323-52371-4 |page=2}}</ref>

==See also==
{{Wiktionarypar|acinus}}
* [[Alveolar gland]]
* [[Intercalated duct]]

==References==
<references/>

==External links==

{{Glands}}
{{Authority control}}

[[Category:Cell anatomy]]


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