Biomaterial Database

[Animal experiment histological-histochemical studies on the development of hearing disorders related to hypothyroidism]. 1975

J Haubrich

It has been known for a long time that hearing deficits may coexist in patients with thyroid disease, but without definite morphologic evidence present to correlate gland dysfunction with hearing disturbances. To clarify this relationship between thyroid dysfunction and hearing disturbances, the guinea pig was employed as an experimental model. 70 animals were thyroidectomized, and maintained in a hypothyroid state for varying periods of time. The animals were then sacrificed, and various histochemical studies then performed. These studies included analysis for glycosidase (beta-galactosidase, beta-glucuronidase, n-acetyl-beta-glucosamide), non-specific esterases, sulfatases, sulghydryl groups as well as mucous substances within the cochlea and saccus endolymphaticus of the experimental animals. Results indicated that hyaluronidase-sensitive mucous substances were increased in the scala of the inner ear. As a consequence of increased deposition of acid mucopolysaccharides, the relationship of potassium to sodium in endolymph and perilymph was found markedly altered. Marked swelling of the chambers of the inner ear was noted, and believed to represent hydropic induction by acid mucopolysaccharide-with consequent alteration of electrolyte relationships ("Electrochemical Theory").

UI	MeSH Term	Description	Entries
D007037	Hypothyroidism	A syndrome that results from abnormally low secretion of THYROID HORMONES from the THYROID GLAND, leading to a decrease in BASAL METABOLIC RATE. In its most severe form, there is accumulation of MUCOPOLYSACCHARIDES in the SKIN and EDEMA, known as MYXEDEMA. It may be primary or secondary due to other pituitary disease, or hypothalamic dysfunction.	Central Hypothyroidism,Primary Hypothyroidism,Secondary Hypothyroidism,TSH Deficiency,Thyroid-Stimulating Hormone Deficiency,Central Hypothyroidisms,Deficiency, TSH,Deficiency, Thyroid-Stimulating Hormone,Hormone Deficiency, Thyroid-Stimulating,Hypothyroidism, Central,Hypothyroidism, Primary,Hypothyroidism, Secondary,Hypothyroidisms,Primary Hypothyroidisms,Secondary Hypothyroidisms,TSH Deficiencies,Thyroid Stimulating Hormone Deficiency,Thyroid-Stimulating Hormone Deficiencies
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D003051	Cochlea	The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.	Cochleas
D004710	Endolymph	The lymph fluid found in the membranous labyrinth of the ear. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Endolymphs
D004950	Esterases	Any member of the class of enzymes that catalyze the cleavage of an ester bond and result in the addition of water to the resulting molecules.	Esterase
D005696	Galactosidases	A family of galactoside hydrolases that hydrolyze compounds with an O-galactosyl linkage. EC 3.2.1.-.	Galactosidase
D005966	Glucuronidase		Endo-beta-D-Glucuronidase,Endoglucuronidase,Exo-beta-D-Glucuronidase,beta-Glucuronidase,Endo beta D Glucuronidase,Exo beta D Glucuronidase,beta Glucuronidase
D006025	Glycosaminoglycans	Heteropolysaccharides which contain an N-acetylated hexosamine in a characteristic repeating disaccharide unit. The repeating structure of each disaccharide involves alternate 1,4- and 1,3-linkages consisting of either N-acetylglucosamine (see ACETYLGLUCOSAMINE) or N-acetylgalactosamine (see ACETYLGALACTOSAMINE).	Glycosaminoglycan,Mucopolysaccharides
D006026	Glycoside Hydrolases	Any member of the class of enzymes that catalyze the cleavage of the glycosidic linkage of glycosides and the addition of water to the resulting molecules.	Endoglycosidase,Exoglycosidase,Glycohydrolase,Glycosidase,Glycosidases,Glycoside Hydrolase,Endoglycosidases,Exoglycosidases,Glycohydrolases,Hydrolase, Glycoside,Hydrolases, Glycoside