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Title	Identification and localization of proteoglycans and lectin reactive glycoconjugates in the inner ear of the developing and adult gerbil
Author	Munyer, Paul David
Date	1994
Affiliation/College	College of Graduate Studies
Department	Pathology and Laboratory Medicine
Extent	205 leaves : illustrations; 29 cm
Source	QU 75 M971i 1994
Subject.MeSH	Academic Dissertations Academic Dissertations--South Carolina Proteoglycans Glycoconjugates
Collection	MUSC Theses and Dissertations
Contributing Institution	Waring Historical Library (MUSC)
Rights	Copyright is held by the author.
Language	English
Type	Text
Format	application/pdf
Media Type	Manuscripts
Resource Identifier	mtd1994_munyer_pd
Abstract	The gerbil inner ear was used as a representative model of the mammalian cochlea in histochemically studying the distribution and influence of proteoglycans (PGs) and other glycoconjugates (GCs) in determining auditory structure and function. The tectorial (TM), basilar (BM), otoconial membranes (OM) and cupula stained strongly with monoclonal antibody against keratan sulfate proteoglycan (KSPG), and less strongly with antibodies against chondroitin sulfate proteoglycan (CSPG) with the availability of more highly specific antibodies against CSPG, it was possible to differentiate between the 4- and 6 sulfated forms of CSPG, which along with KSPG, were preferentially localized in the upper TM from birth and in the margins of the BM after day 10 of life sites of potential PG origin were also demonstrated near developing tunnel of corti. Other GCs in the inner ear were analyzed with a battery of twenty horseradish peroxidase-conjugated lectins. Lectin binding profiles suggested that the limbal zone fibrous layer contained mainly O-glycosidically linked oligosaccharides whereas the middle zone's medial fibrous layer contained both 0- and N-linked chains. The remaining regions of the TM contained various N-linked oligosaccharides, especially in cover net. Differences in GC composition between TM zones implies a role for different carbohydrate classes in determining biomechanical properties. Specialized ion transport cells within the mature inner ear were also investigated utilizing lectin methods. N-linked oligosaccharides were demonstrated and transport fibrocytes in the suprastrial and inferior spiral lamina regions differed from transport epithelial cells in exhibiting reactivity with certain lectins specific for O-linked chains. The results provide good evidence for the preferential distribution of specific proteoglycans and presumably uncharacterized glycoproteins within distinct domains of the gelatinous membranes of the inner ear. Also, their appearance in BM coincides with the critical period of postnatal development. Overall effects of PGs in the TM and BM are most likely reflected in the contribution to the membranes effective mass and stiffness, which in turn could be involved the mechanical tuning of the TM/BM complex. Lectin binding profiles also suggest that this preferential distribution of specific GCs possibly influences the biophysical and physiological properties of membranes.

Identification and localization of proteoglycans and lectin reactive glycoconjugates in the inner ear of the developing and adult gerbil

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