Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experiments were performed to indentify the series elastic component (SEC) in intact dog carotid artery held at in situ length. The vessels were studied during excitation of the muscle with norepinephrine and after metabolic poisoning with potassium cyanide and sodium iodoacetate. Static circumferential stress-strain curves and stress-quick-release stiffness curves were examined to evaluate Maxwell and Voigt model elements. The vessels were studied at 33, 36, and 39 degrees C. Temperature variations altered active stress, but did not alter connective tissue properties or the Maxwell SEC stiffness. The Voigt model SEC stiffness was altered, but this was secondary to changes in active stress. Thus, most of the SEC is separate from the contractile apparatus. Other vessels were treated with elastase, collagenase, or hyaluronidase to digest the connective tissue components of the wall. Hyaluronidase had no effect on mechanics. Elastase and collagenase altered connective tissue properties, but only elastase unequivocally altered SEC stiffness. This analysis indicated 1) that the carotid artery wall is better represented by a Maxwell model than a Voigt model, and 2) that the SEC in intact carotid artery is primarily elastin.
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PMID:Identification of smooth muscle series elastic component in intact carotid artery. 19 Aug 98

Enzymatic depolymerization of hyaluronic acid (HA) is accompanied by the release of reducing ends irrespective of the linkage cleaved. In this investigation we have examined HA exposed to oxygen-derived free radicals (oxy radicals) in order to determine whether reducing ends are released upon depolymerization. Reducing ends were detected by the assay of Park and Johnson, which is a non-specific but sensitive assay for reducing ends, but only to a minimal degree by the Reissig modification of the Morgan Elson reaction, which will detect N-acetylglucosamine at the reducing end. Exposure of a sample of HA, pre-exposed to streptomyces hyaluronidase, to an oxy radical flux did not result in a decrease in Morgan Elson reactivity thus indicating that post cleavage modification of the reducing end by further reaction with oxy radicals does not account for the lack of Morgan Elson reactivity. In addition reducing ends were also detected by reaction with radiolabelled cyanide to the degree predicted by molecular weight. These findings were interpreted as being consistent with the hypothesis that oxy radical induced depolymerization of HA occurs by preferential cleavage of the glucuronidic linkage thus leaving D-glucuronic acid at the reducing end.
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PMID:The generation of reducing ends by exposure of hyaluronic acid to oxygen derived free radicals. 346 Mar 16