Olfactory glands, also known as Bowman's glands, are a type of

nasal gland The nasal glands are the seromucous glands in the respiratory The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and pla ...

situated in the

olfactory mucosa The olfactory mucosa is located in the upper region of the nasal cavity and is made up of the olfactory epithelium and the underlying lamina propria, connective tissue containing fibroblasts, blood vessels, Bowman's glands and bundles of fine ...

, beneath the

olfactory epithelium The olfactory epithelium is a specialized epithelial tissue inside the nasal cavity that is involved in smell. In humans, it measures 9 cm2 and lies on the roof of the nasal cavity about 7 cm above and behind the nostrils. The olfactory ...

, in the

lamina propria The lamina propria is a thin layer of connective tissue that forms part of the moist linings known as mucous membranes or mucosae, which line various tubes in the body, such as the respiratory tract, the gastrointestinal tract, and the urogenit ...

, a connective tissue also containing

fibroblasts A fibroblast is a type of biological cell that synthesizes the extracellular matrix and collagen, produces the structural framework ( stroma) for animal tissues, and plays a critical role in wound healing. Fibroblasts are the most common cells ...

, blood vessels and bundles of fine

axons An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...

from the olfactory

neurons A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa ...

. An olfactory gland consists of an

acinus An acinus (; plural, acini; adjective, acinar 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 ...

in the lamina propria and a secretory duct going out through the olfactory epithelium. Electron microscopy studies show that olfactory glands contain cells with large secretory vesicles. Olfactory glands secrete the gel-forming

mucin Mucins () are a family of high molecular weight, heavily glycosylated proteins (glycoconjugates) produced by epithelial tissues in most animals. Mucins' key characteristic is their ability to form gels; therefore they are a key component in most ...

protein

MUC5B Mucin-5B (MUC-5B) is a protein that in humans is encoded by the ''MUC5B'' gene and by ''Muc5b'' gene in mouse. It is one of the five gel-forming mucins. MUC-5B can be found in whole saliva, normal lung mucus, and cervical mucus. In some disease ...

. They might secrete proteins such as lactoferrin,

lysozyme Lysozyme (EC 3.2.1.17, muramidase, ''N''-acetylmuramide glycanhydrolase; systematic name peptidoglycan ''N''-acetylmuramoylhydrolase) is an antimicrobial enzyme produced by animals that forms part of the innate immune system. It is a glycoside ...

amylase An amylase () is an enzyme that catalyses the hydrolysis of starch (Latin ') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large amounts of ...

and

IgA Iga may refer to: Arts and entertainment * Ambush at Iga Pass, a 1958 Japanese film * Iga no Kagemaru, Japanese manga series * Iga, a set of characters from the Japanese novel '' The Kouga Ninja Scrolls'' Biology * ''Iga'' (beetle), a g ...

, similarly to

serous glands Serous glands secrete serous fluid. They contain serous acini, a grouping of serous cells that secrete serous fluid, isotonic with blood plasma, that contains enzymes such as alpha-amylase. Serous glands are most common in the parotid gland and ...

. The exact composition of the secretions from olfactory glands is unclear, but there is evidence that they produce

odorant-binding protein Odorant-binding proteins (OBPs) are small (10 to 30 kDa) soluble proteins secreted by auxiliary cells surrounding olfactory receptor neurons, including the nasal mucus of many vertebrate species and in the sensillar lymph of chemosensory sensilla of ...

Function

The Olfactory glands are tubuloalveolar glands surrounded by

Olfactory receptors Olfactory receptors (ORs), also known as odorant receptors, are chemoreceptors expressed in the cell membranes of olfactory receptor neurons and are responsible for the detection of odorants (for example, compounds that have an odor) which give ri ...

and Sustentacular cells in the olfactory epithelium. These glands produce mucous to lubricate the olfactory epithelium and dissolve odorant-containing gases. Several olfactory binding proteins are produced from the olfactory glands that help facilitate the transportation of odorants to the olfactory receptors. These cells exhibit the mRNA to transform growth factor α, stimulating the production of new olfactory receptor cells.

References

External links

Slide at ouhsc.edu
Olfactory system {{anatomy-stub

Function

See also

References

External links