Biomaterial Database

Ultrastructural evidence of a merocrine secretion in the human endolymphatic sac. 1991

H Rask-Andersen, and N Danckwardt-Lillieström, and F H Linthicum, and W F House

House Ear Institute, Los Angeles, California.

The results of a light and transmission electron microscopic analysis of an endolymphatic sac (ES) from a patient suffering from episodic vertigo, tinnitus, and hearing loss are presented. A biopsy of the intraosseous portion of the ES was obtained during a translabyrinthine approach to section the vestibular nerve in the internal acoustic meatus. The material consisted mainly of tubular epithelial structures filled with heavily stained material. Pathologically dilated and degranulated rough endoplasmic reticuli and disaggregation of polyribosomes with accumulation of solitary ribosomes in the cytosol and endoplasmic reticulum suggested a disturbed epithelial cell protein synthesis. Ultrastructural evidence of an increased merocrine secretion of glycoprotein conjugates into the ES was noted. This made it possible to analyze the presumed intracellular secretory pathways. An increased number of intraepithelial lymphocytes and monocytes was observed. Since the inner ear had been subjected to surgical intervention before the vestibular nerve section, no conclusions can be drawn as to whether the patient's symptoms were related to the disturbed protein metabolism and hypersecretion of glycoprotein conjugates into the ES. The findings support earlier experimental results that indicate that the ES has not only a resorptive function but also a secretory one.

UI	MeSH Term	Description	Entries
D008575	Meniere Disease	A disease of the inner ear (LABYRINTH) that is characterized by fluctuating SENSORINEURAL HEARING LOSS; TINNITUS; episodic VERTIGO; and aural fullness. It is the most common form of endolymphatic hydrops.	Meniere's Disease,Meniere's Syndrome,Vertigo, Aural,Auditory Vertigo,Aural Vertigo,Ménière Disease,Ménière's Disease,Ménière's Vertigo,Otogenic Vertigo,Auditory Vertigos,Disease, Meniere,Disease, Meniere's,Disease, Ménière,Disease, Ménière's,Diseases, Ménière,Diseases, Ménière's,Meniere Syndrome,Menieres Disease,Menieres Syndrome,Ménière Diseases,Ménière Vertigo,Ménière's Diseases,Ménière's Vertigos,Ménières Disease,Ménières Vertigo,Otogenic Vertigos,Syndrome, Meniere's,Vertigo, Auditory,Vertigo, Ménière's,Vertigo, Otogenic,Vertigos, Auditory,Vertigos, Ménière's,Vertigos, Otogenic
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008870	Microtubules	Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.	Microtubule
D009464	Neuroma, Acoustic	A benign SCHWANNOMA of the eighth cranial nerve (VESTIBULOCOCHLEAR NERVE), mostly arising from the vestibular branch (VESTIBULAR NERVE) during the fifth or sixth decade of life. Clinical manifestations include HEARING LOSS; HEADACHE; VERTIGO; TINNITUS; and FACIAL PAIN. Bilateral acoustic neuromas are associated with NEUROFIBROMATOSIS 2. (From Adams et al., Principles of Neurology, 6th ed, p673)	Acoustic Neuroma,Melanocytic Vestibular Schwannoma,Schwannoma, Acoustic,Schwannoma, Vestibular,Acoustic Neuroma, Cerebellopontine Angle,Acoustic Tumor,Angle Tumor,Cerebellopontine Angle Acoustic Neuroma,Cerebellopontine Angle Tumor,Neurilemmoma, Acoustic,Neurilemoma, Acoustic,Neurinoma of the Acoustic Nerve,Neurinoma, Acoustic,Neuroma, Acoustic, Unilateral,Vestibular Schwannoma,Acoustic Neurilemmoma,Acoustic Neurilemmomas,Acoustic Neurilemoma,Acoustic Neurilemomas,Acoustic Neurinoma,Acoustic Neurinomas,Acoustic Neuromas,Acoustic Schwannoma,Acoustic Schwannomas,Acoustic Tumors,Angle Tumor, Cerebellopontine,Angle Tumors,Angle Tumors, Cerebellopontine,Cerebellopontine Angle Tumors,Melanocytic Vestibular Schwannomas,Neurilemmomas, Acoustic,Neurilemomas, Acoustic,Neurinomas, Acoustic,Neuromas, Acoustic,Schwannoma, Melanocytic Vestibular,Schwannomas, Acoustic,Schwannomas, Melanocytic Vestibular,Schwannomas, Vestibular,Tumor, Acoustic,Tumor, Angle,Tumor, Cerebellopontine Angle,Tumors, Acoustic,Tumors, Angle,Tumors, Cerebellopontine Angle,Vestibular Schwannoma, Melanocytic,Vestibular Schwannomas,Vestibular Schwannomas, Melanocytic
D011132	Polyribosomes	A multiribosomal structure representing a linear array of RIBOSOMES held together by messenger RNA; (RNA, MESSENGER); They represent the active complexes in cellular protein synthesis and are able to incorporate amino acids into polypeptides both in vivo and in vitro. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Polysomes,Polyribosome,Polysome
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D003594	Cytoplasmic Granules	Condensed areas of cellular material that may be bounded by a membrane.	Cytoplasmic Granule,Granule, Cytoplasmic,Granules, Cytoplasmic
D004712	Endolymphatic Sac	The blind pouch at the end of the endolymphatic duct. It is a storage reservoir for excess ENDOLYMPH, formed by the blood vessels in the membranous labyrinth.	Endolymphatic Sacs,Sac, Endolymphatic,Sacs, Endolymphatic
D004721	Endoplasmic Reticulum	A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)	Ergastoplasm,Reticulum, Endoplasmic
D005260	Female		Females