Responses of the endolymphatic sac to perilymphatic injections and withdrawals: evidence for the presence of a one-way valve
Responses of the endolymphatic sac to perilymphatic injections and withdrawals: evidence for the presence of a one-way valve
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DOI：
10.1016/j.heares.2003.12.018
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发表时间：
2004-05-01
期刊：
影响因子：
2.8
通讯作者：
Rask-Andersen, H
中科院分区：
文献类型：
--
作者：
Salt, AN;Rask-Andersen, H
虽然内淋巴囊（ES）被认为是内淋巴容量调节的主要部位，但我们对它如何响应容量和压力变化的知识有限。在以前的出版物中，我们证明了K+，Na+和内淋巴囊电位（ESP）的变化，从体积注入到耳蜗中阶，并从中阶撤出。在本研究中，我们比较了耳蜗鼓阶注射和拔出对内淋巴囊的影响。假设在耳的耳蜗和前庭隔室的内淋巴和外淋巴中诱导类似的压力变化。外淋巴注射和撤回引起的压力变化并没有引起类似的K+在ES的变化。大多数外淋巴液的撤出导致K+和ESP减少的囊，但很少注射引起任何可测量的变化的囊。来自ES的压力测量结果表明，向管腔传输压力是方向敏感的，负压比正压传输更有效。在其他实验中，对耳道施加次声刺激导致ES中的K+增加。这些生理测量结果表明，内淋巴管可能被前庭持续正压关闭，但在压力波动期间打开。内淋巴管进入前庭的解剖学研究表明，内淋巴管的膜窦可以作为一个机械阀，当施加压力时，限制内淋巴从球囊流向内淋巴囊。因此，这种结构可以发挥重要作用，内淋巴容量的调节。(C)2004 Elsevier B.V.保留所有权利。
Although the endolymphatic sac (ES) is thought to be a primary site for endolymph volume regulation, we have limited knowledge of how it responds to volume and pressure changes. In a prior publication, we demonstrated changes of K+, Na+ and endolymphatic sac potential (ESP) resulting from volume injections into, and withdrawals from, scala media of the cochlea. In the present study, we compared the influence of injections into and withdrawals from scala tympani of the cochlea on the endolymphatic sac. It is assumed that similar pressure changes are induced in endolymph and perilymph of both the cochlear and vestibular compartments of the ear. Pressure changes induced by the perilymphatic injections and withdrawals did not induce similar K+ changes in the ES. The majority of perilymph withdrawals caused K+ and ESP reductions in the sac, but few injections caused any measurable changes in the sac. Pressure measurements from the ES demonstrated that transmission of labyrinthine pressures to the lumen was directionally sensitive, with negative pressure transmitted more effectively than positive. In other experiments, application of infrasonic stimulation to the ear canal resulted in K+ increase in the ES. These physiological measurements suggest that the endolymphatic duct may be closed by sustained positive pressure in the vestibule but open during pressure fluctuations. Study of the anatomy where the endolymphatic duct enters the vestibule suggests that the membranous sinus of the endolymphatic duct could act as a mechanical valve, limiting the flow of endolymph from the saccule to the endolymphatic sac when pressure is applied. This structure could therefore play an important role in endolymph volume regulation. (C) 2004 Elsevier B.V. All rights reserved.