Acinus

{{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 cells that resembles a many-lobed "berry", such as a raspberry (''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 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 (Cowper's) glands The thyroid 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 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==

Category:Cell anatomy