Nasal mucosa
The nasal mucosa is a mucous membrane that covers the turbinates and the interior of the nasal cavities . In the area of the lower and middle turbinate, it is called the pars respiratoria (breathing part). It is used to clean, humidify and warm the air you breathe. The lining of the upper nasal cavity is called the olfactory mucous membrane ( pars olfactoria ), it is used for odor perception.
construction
The respiratory part of the nasal mucosa has a ciliated epithelium , which sits on a layer of its own ( lamina propria mucosae ). The cells of the ciliated epithelium have 50 to 300 very fine cilia (cilia) that protrude into the mucous layer. Goblet cells are scattered between these ciliated epithelial cells , which together with the nasal glands of the anterior nasal area produce nasal secretions . The mucous membrane is completely covered by this layer. The nasal mucosa is regenerated by the so-called nasal cycle . In the area of the olfactory mucous membrane, the multi-row columnar epithelium has no kinocilia and there are no goblet cells, instead olfactory cells are embedded.
In the transition from the outer skin to the ciliated epithelium of the nasal mucous membrane, the Kiesselbachi locus , a vascularized mucous membrane, is located in the anterior, lower part of the nasal septum .
Functions
The nasal mucous membrane has an important filter function to protect against inhaled foreign bodies and pathogens. They stick to the layer of mucus. The secretion layer is gel-like on the surface and liquid underneath. The cilia beat about 450 to 800 times per minute. In the case of flickering, a distinction is made between a short effective phase , in which the shaft of the cilia is straight and the tip is curved in the gel layer, and a longer recovery phase , in which the shaft is curved and the tip moves back in the watery layer. This flicker current ( mucociliary clearance ) pushes the mucous layer in the direction of the choana and thus into the throat , which takes about 10 to 15 minutes from the nasal entrance to the choana. For the defense against pathogens, specific antibodies, especially immunoglobulin A , are produced in the mucous membrane, with which the pathogens can be repelled. The mechanical binding of bacteria in the nasal secretion also plays a major role in defense against infection.
Due to the good blood circulation in the mucous membrane, the breathing air is tempered within a few seconds. In the area of the nasopharynx , the temperature of the air we breathe is 32–34 ° C; the necessary heating or cooling works at outside temperatures of −8 to 40 ° C. Only at outside temperatures below −40 ° C does the temperature in the nasopharynx drop to 31 ° C. The evaporated water from the nasal secretion is released into the air we breathe in order to moisten it. The relative humidity increases to about 80%. In the adjoining airways, the air is tempered to 37 ° C and a humidity of 98% is generated, which is a prerequisite for an undisturbed gas exchange in the lungs.
Like all mucous membranes is the nasal mucosa and for uptake ( absorption capability). The size and absorption capacity are mostly unsuitable for the uptake of larger amounts of active ingredient in the context of systemic therapy , exceptions are, for example, treatment with desmopressin in diabetes insipidus . But even locally introduced drugs such as nasal drops can get into the body to such an extent that they cause undesirable side effects. The sympathomimetics it contains can trigger respiratory depression or even a coma in infants. Intoxicants such as snuff , amphetamine and cocaine are also consumed through the nasal mucosa.
Diseases and dysfunction
Inflammation of the nasal mucosa is called rhinitis . It can be caused by pathogens such as viruses and bacteria, by irritating substances and by allergies. The acute rhinitis , popularly referred to as "runny nose", is one of the most common viral infections of humans.
The nasal tassel larvae attack the nasal mucous membrane mainly from ungulates . Trichosomoides nasalis is a parasite of the nasal mucosa in mice .
Individual evidence
- ↑ Ulrike Bommas-Ebert, Philipp Teubner, Rainer Voß: Kurzlehrbuch Anatomie . 3rd edition, Georg Thieme, Stuttgart 2011, ISBN 9783131517937 , pp. 111-112.
- ↑ a b Horst Ganz, V. Jahnke: Ear, nose and throat medicine . Walter de Gruyter, 2013, ISBN 978-3-11-081344-9 , p. 112 .
- ↑ D. Becker et al .: ENT practice today . Springer, Berlin 2013, ISBN 978-3-642-57007-0 , pp. 62 .
- ↑ E. Oberdisse: General and special pharmacology and toxicology: Part 1 General pharmacology, chemotherapy, endocrine system, vitamins, toxicology . Springer, Berlin 2013, ISBN 978-3-642-69018-1 , pp. 14 .
- ↑ Hans-Peter Zenner: Practical therapy of ENT diseases: operating principles, conservative therapy, chemo- and radiochemotherapy, drug therapy, physical therapy, rehabilitation, psychosocial aftercare . Schattauer, Stuttgart 2008, ISBN 978-3-7945-2264-4 , pp. 230-241 .
- ^ Richard L. Wall, David Shearer: Veterinary Ectoparasites: Biology, Pathology and Control . 2nd Edition. John Wiley & Sons, 2008, ISBN 978-0-470-68022-3 , pp. 121 .
- ↑ F. Redha and B. Horning: Trichosomoides nasalis in the nasal cavities of a golden hamster . In: Swiss Archives for Veterinary Medicine . Vol. 122, No. 6, 1980, pp. 357-358.
