endolymph
Quick Summary
Endolymph is a fluid found within the membranous labyrinth of the inner ear. It is unique among extracellular fluids due to its high concentration of potassium ions and low concentration of sodium ions. This ionic composition differs significantly from perilymph, another fluid in the inner ear, and from other bodily extracellular fluids.1
The formation and maintenance of endolymph are not fully understood, but it is believed to be produced from perilymph through selective ion transport across the Reissner membrane. The stria vascularis, located in the cochlear duct, plays a crucial role in maintaining the high potassium-to-sodium ratio in the endolymph.1
Endolymph is essential for the function of the semicircular canals, which are responsible for sensing head rotation and maintaining balance. Movement of the head causes the endolymph to displace a jelly-like structure called the cupula, which in turn stimulates hair cells. This process generates neural impulses sent to the brain, enabling coordinated movement and visual stability. Abnormal buildup of endolymph can lead to conditions like Meniere disease, causing symptoms such as hearing loss and vertigo.2
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human earInner ear…filled with a fluid called endolymph, which has a markedly different ionic content from perilymph. Because the membranous labyrinth is a closed system, the endolymph and perilymph do not mix.
Read More…filled with a fluid called endolymph, which has a markedly different ionic content from perilymph. Because the membranous labyrinth is a closed system, the endolymph and perilymph do not mix.
Read More- human earEndolymph and perilymph
The perilymph, which fills the space within the bony labyrinth surrounding the membranous labyrinth, is similar, but not identical, in composition to other extracellular fluids of the body, such as cerebrospinal fluid. The concentration of sodium ions in the perilymph is high…
Read MoreThe perilymph, which fills the space within the bony labyrinth surrounding the membranous labyrinth, is similar, but not identical, in composition to other extracellular fluids of the body, such as cerebrospinal fluid. The concentration of sodium ions in the perilymph is high…
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- human earTransduction of mechanical vibrations
…potential, which exists between the endolymph and perilymph. This direct current potential difference is about +80 millivolts and results from the difference in potassium content between the two fluids. It is thought to be maintained by the continual transport of potassium ions from the perilymph into the cochlear duct by…
Read More…potential, which exists between the endolymph and perilymph. This direct current potential difference is about +80 millivolts and results from the difference in potassium content between the two fluids. It is thought to be maintained by the continual transport of potassium ions from the perilymph into the cochlear duct by…
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human sensory receptionVestibular sense (equilibrium)…are filled with fluid called endolymph; in the ampulla of each canal are fine hairs equipped with mechanosensing stereocilia and a kinocilium that project into the cupula, a gelatinous component of the ampulla. When rotation begins, the cupula is displaced as the endolymph lags behind, causing the stereocilia to bend…
Read More…are filled with fluid called endolymph; in the ampulla of each canal are fine hairs equipped with mechanosensing stereocilia and a kinocilium that project into the cupula, a gelatinous component of the ampulla. When rotation begins, the cupula is displaced as the endolymph lags behind, causing the stereocilia to bend…
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mechanoreceptionRotation receptorsEndolymph displacement through a canal makes the cupula move aside, as if it were a swinging door. In vertebrates, the inertial lag of the endolymph at the onset of rotation is very brief, the fluid catching up with the angular velocity of the labyrinth within…
Read MoreEndolymph displacement through a canal makes the cupula move aside, as if it were a swinging door. In vertebrates, the inertial lag of the endolymph at the onset of rotation is very brief, the fluid catching up with the angular velocity of the labyrinth within…
Read More- Ménière disease
…is an excessive amount of endolymph, the fluid in the labyrinth of the inner ear.
Read More…is an excessive amount of endolymph, the fluid in the labyrinth of the inner ear.
Read More - semicircular canalFunction
…contains a fluid known as endolymph, which is also present in the cochlea, and the crista, a cone-shaped structure lined with hair cells and supporting cells. The hair cells form stereocilia, protrusions that extend into the crista. The longest of the stereocilia are the kinocilia, which point in a single…
Read More…contains a fluid known as endolymph, which is also present in the cochlea, and the crista, a cone-shaped structure lined with hair cells and supporting cells. The hair cells form stereocilia, protrusions that extend into the crista. The longest of the stereocilia are the kinocilia, which point in a single…
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