Duct (anatomy)

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-632-7753

Overview

In anatomy and physiology, a duct is a circumscribed channel leading from an exocrine gland or organ.

Types of ducts

Examples include:

Duct	From	To	Carries
Lactiferous duct	mammary gland	nipple	milk
Cystic duct	spleen	common bile duct	bile
Common hepatic duct	liver	common bile duct	bile
Common bile duct	common hepatic duct and cystic duct	pancreatic duct	bile
Pancreatic duct	pancreas	hepatopancreatic ampulla	bile and pancreatic enzymes
Ejaculatory duct	vas deferens	urethra	semen
Parotid duct	parotid gland	mouth	saliva
Submaxillary duct	submaxillary gland	mouth	saliva
Major sublingual duct	sublingual gland	mouth	saliva
Bartholin’s ducts	Bartholin’s glands	Vulva	Bartholin’s fluid

Duct system

As ducts travel from the acinus which generates the fluid to the target, the ducts become larger and the epithelium becomes thicker. The parts of the system are classified as follows:

Type of duct	Epithelium	Surroundings
intralobular duct	simple cuboidal	parenchyma
interlobular duct	simple columnar	connective tissue
interlobar duct	stratified columnar	connective tissue

Some sources consider “lobar” ducts to be the same as “interlobar ducts”, while others consider lobar ducts to be larger and more distal from the acinus. For sources that make the distinction, the interlobar ducts are more likely to classified with simple columnar epithelium (or pseudostratified epithelium), reserving the stratified columnar for the lobar ducts.

Additional images

Section of submaxillary gland of kitten. Duct semidiagrammatic. X 200.
Section of portion of mamma.

External links

Template:EMedicineDictionary
Template:Dorlands
Template:UCDavisOrganology – “Exocrine gland (LM, Low)”
Overview at uwa.edu.au
Overview at siumed.edu

Template:Glands

nl:Buis (anatomie)

Template:WikiDoc Sources