Ampullary cupula
Ampullary cupula[edit | edit source]
Ampullary Cupula[edit | edit source]
The ampullary cupula is a gelatinous structure located within the inner ear of vertebrates, playing a crucial role in the detection of angular acceleration and balance. It is part of the vestibular system, which is responsible for maintaining equilibrium and spatial orientation.
Anatomy[edit | edit source]
The ampullary cupula is situated within the ampulla of each of the three semicircular canals in the inner ear. Each semicircular canal is oriented in a different plane, allowing for the detection of rotational movements in three-dimensional space. The ampulla is a widened area at the base of each canal, and it houses the crista ampullaris, a sensory epithelium that contains hair cells.
The cupula itself is a gelatinous, dome-shaped structure that extends from the crista ampullaris to the roof of the ampulla. It is composed of a glycoprotein matrix and is buoyant in the surrounding endolymph, the fluid that fills the semicircular canals.
Function[edit | edit source]
The primary function of the ampullary cupula is to detect changes in head rotation. When the head rotates, the inertia of the endolymph causes it to lag behind the movement of the canal walls. This relative motion of the endolymph exerts a force on the cupula, causing it to bend.
The bending of the cupula results in the deflection of the stereocilia and kinocilium on the hair cells of the crista ampullaris. This mechanical deformation opens ion channels in the hair cells, leading to a change in the rate of neurotransmitter release and the generation of nerve impulses. These impulses are transmitted via the vestibular nerve to the brain, where they are integrated with other sensory information to maintain balance and spatial orientation.
Clinical Significance[edit | edit source]
Disorders affecting the ampullary cupula can lead to vestibular dysfunction, resulting in symptoms such as vertigo, dizziness, and balance disorders. Conditions such as benign paroxysmal positional vertigo (BPPV) can occur when debris, known as otoconia, dislodges and affects the normal function of the cupula.
Related Pages[edit | edit source]
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
WikiMD's Wellness Encyclopedia |
Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates, categories Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD