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)

A potential enzymic mechanism for the degradation of glycosaminogly cans was characterised using enzymes found in rheumatoid synovial fluid from the knee joint. This mechanism involves a true hyluronidase together with the concerted action of beta-glucuronidase and beta-N-acetylhexosaminidase. The contribution of the exopolysaccharidases to hyaluronate degradation was demonstrated by the use of specific inhibitors, while the distinct identity of a true hyaluronidase was shown by ammonium sulphate and agarose gel column fractionations. Only the hyluronidase fraction was capable of degrading high molecular weight hyaluronate. The exopolysaccharidase activities were shown to be markedly elevated in rheumatoid as compared to osteoarthritic synovial fluid and also normal serum. On the other hand, hyluronidase was similarly active in rheumatoid and osteoarthritic synovial fluids; both these levels were lower than that of normal human serum. Hyaluronidase in synovial fluid may thus be derived by diffusion from serum, since it is of relatively low molecular weight (60 000). The pH requirements of this enzyme system and the strong inhibition of hyaluronidase by synovial fluid make it unlikely that the mechanism operates extracellularly. It is proposed that as a lysosomal mechanism, however, it is an important contributing factor in the chronic erosion process characteristic of rheumatoid arthritis.
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PMID:The characterisation and function of the polysaccharidases of human synovial fluid in rheumatoid and osteoarthritis. 23 48

A sensitive dye-binding assay was employed to study the hyaluronidase associated with temperate and virulent phages infected group A streptococci. Some enzyme was detectable in each purified phage preparation examined, but differences of several orders of magnitude separated the lower enzyme levels in virulent phages that required the addition of hyaluronidase for plaque formation and the higher levels in temperate phages that did not. Infection by virulent phage A25 was accompanied by the production of levels of hyaluronidase proportionate to the average burst size. Hyaluronidase was produced during infection by temperate phages at a much higher level than could be accounted for by the number of phage particles formed. The major portion of this hyaluronidase was free and apparently unassociated with phage or phage fragments. The phage-associated enzyme was tightly bound but could be released and solubilized by treatment with urea.
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PMID:Hyaluronidase activity of bacteriophages of group A streptococci. 32 52

Antibodies to proteoglycan (PG) and glycoprotein of bovine nasal cartilage were conjugated with fluorescein isothiocyanate and with horseradish peroxidase. Hyaluronidase digestion of cartilage tissue-specimens increased the intensity of immune reactions; pronase digestion or extraction with 4 M guanidinium chloride abolished the staining. In the intercellular matrix fine filaments beaded with small granules were seen forming an irregular network. The interstices of the network are filled with collagen fibers linked together by the filaments and granules. In view of the linear conformation of core proteins of PGs and the globular conformation of glycoproteins (link proteins), it may be supposed that the granules and filaments represent these two protein components of PG-aggregates. In chondrocytes a homogeneous staining was recorded in the endoplasmic reticulum, in the juxtanuclear areas and in several smooth-walled vesicles and elongated areas situating subjacent to the cell membrane. In contrast to the extracellular immune reactions, this homogeneous intracellular staining was never enhanced by hyaluronidase digestion. This is interpreted in the sense that conformation changes of molecules secreted, and the aggregation of PGs, occur extracellularly.
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PMID:The localization of proteoglycans and glycoproteins in the hyaline cartilage. 33 74

Hyaluronidase, an enzyme which depolymerizes the mucopolysaccharide hyaluronic acid, appears to be tolerated by the human central nervous system and in the anterior chamber of the rabbit eye. Two patients with hydrocephalus and meningomyelocele had their condition curtailed by intraventricular injections of hyaluronidase, and in a third patient its use permitted delay of shunting. It was apparently effective in preventing a reaccumulation of cystic fluid in an intramedullary neurofibroma, and in reversing adverse effects of adhesive arachnoiditis of the spinal cord. Hylauronidase seems worthy of further investigation in disorders of the central nervous system.
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PMID:Use of hyaluronidase in the central nervous system. 45 58

Studies have been made on the effect of trypsin, chymotrypsin, pronase, lipases, hyaluronidase and digitonin on electrophysiological properties of the neurons of the snail H. pomatia under external application. Proteases and lipases gradually depolarize the neuronal membrane, decrease the amplitude and prevent the onset of action potentials, initially increase and then decrease the membrane resistance. The decrease in the membrane resistance coincides with the period of maximum inhibition of resting and action potentials in the neurons. The enzymes studied do not affect the membrane capacitance. Changes in electrophysiological characteristics induced by the enzymes are partially reversible provided the preparation is soaked in Ringer's solution for a sufficient time. Digitonin rapidly and irreversibly depolarizes the membrane, decreases its resistance and blocks action potentials. Hyaluronidase does not significantly affect neuronal electrophysiological properties when applied solely, but facilitates the development of changes during subsequent effect of proteases.
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PMID:[Effect of hydrolases and digitonin on the electrophysiological characteristics of the neurons of the snail, Helix pomatia]. 67 79

Smears of washed spermatozoa are treated by an indirect immunocytochemical technique. The first antiserum used is prepared in rabbits against ovine (or bovine) hyaluronidase. A sheep antiserum against rabbit globulin, labeled with fluorescerine or peroxidase, is used at the second reagent. Hyaluronidase is localized in the anterior segment of the sperm acrosomes of ram, bull and other species. The specificity of the immunocytochemical staining is checked by appropriate controls. Anti-hyaluronidase serum adsorbed with the antigen, or normal serum, is used as the first reagent. The spermatozoa are also treated with the labeled antiserum only.
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PMID:[Immunocytochemical localization of hyaluronidase in the spermatozoa of domestic mammals]. 80 70

To evaluate hyaluronidase's effect in reducing post-infarction myocardial necrosis, we randomized 91 patients with anterior infarction to control (45) or to hyaluronidase-treatment (46) groups. A 35-lead precordial electrocardiogram was recorded on admission and seven days later. Hyaluronidase was administered intravenously after the first electrocardiogram and every six hours for 48 hours. QRS-complex changes were analyzed to assess the drug's effect. Precordial sites with ST-segment elevation (larger than or equal to 0.15 mV) on the initial electrocardiogram that retained an R wave were considered vulnerable for the development of electrocardiographic signs of necrosis. The sum of R-wave voltages of vulnerable sites fell more in the control group than in the hyaluronidase group (70.9 +/- 3.6 per cent [+/- 1 S.E.M.] vs 54.2 +/- 5.0 per cent P less than 0.01). Q waves appeared in 59.3 +/- 4.9 per cent of the vulnerable sites in control versus 46.4 +/- 4.9 per cent in hyaluronidase-treated patients (P less than 0.05). Thus, hyaluronidase reduced the frequency of electrocardiographic signs of myocardial necrosis.
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PMID:Favorable effects of hyaluronidase on electrocardiographic evidence of necrosis in patients with acute myocardial infarction. 84 10

The effect of hyaluronidase on the early course of acute myocardial infarction was evaluated in closed chest anesthetized pigs. One hour after balloon catheter occlusion of the left anterior descending coronary artery, hyaluronidase (500 units/kg body weight) was rapidly infused in 10 animals while 9 received no treatment. The animals were than observed over the next 4 hours. Cardiac output, heart rate, mean arterial pressure and left atrial pressure were not significantly affected by treatment. Heart rate increased and arterial pressure decreased in each group to a comparable degree of 5 hours, but left atrial pressure and cardiac output were unaffected. Precordial S-T segment mapping revealed no significant difference between the two groups. S-T segments rose to a comparable degree in each group and peaked before 1 hour. Hyaluronidase had no acute effects on the S-T segment map in the first 30 minutes after infusion or during the subsequent return of the map toward control level. Slightly lower S-T segments in the hyaluronidase-treated group at 5 hours was of borderline significance but was attributed to factors other than the drug intervention. Changes in ventricular wall motion were assessed angiographically, and all animals manifested akinetic or dyskinetic segments. A significant reduction in shortening fraction of involved segments was seen after occlusion, but no difference was observed between the two groups at 5 hours. Shortening fraction of the combined anterior and anteropical segments decreased from 66 +/- 10 to 20 +/- 6 percent at 5 hours in the hyaluronidase group (no. = 7) whereas in the control group (no. = 6) it decreased from 68 +/- 6 to 28 +/- 9 percent. Comparable increases in end-diastolic volume were also present at 5 hours in each group. Volumes increased from 80.6 +/- 5.1 to 97.5 +/- 6.4 ml3 at 5 hours (P less than 0.05) in the hyaluronidase-treated group (no. = 10) compared with 86.9 +/- 8.9 to 104.8 +/- 11.0 ml3 (P less than 0.05) in the control group (no. = 8). Hyaluronidase did not alter the early course of acute myocardial infarction in pigs. Species differences may contribute to different results reported to date.
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PMID:Failure of hyaluronidase to alter the early course of acute myocardial infarction in pigs. 94 84

Acrosin and hyaluronidase have been localized in the acrosomal region of ram spermatozoa using specific antibodies raised against the highly purified enzymes. Hyaluronidase staining was denser at the periphery of the sperm head; whereas acrosin staining was denser in the equatorial region and appeared to be bound to the inner acrosomal membrane.
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PMID:Acrosomal enzymes: Immunochemical localization of acrosin and hyaluronidase in ram spermatozoa. 110 35

Hyaluronidase is a component of the acrosome of bovine spermatozoa. Utilizing fluorescein and peroxidase-labelled antibodies, the enzyme has been localised at both the light and electron microscopic levels. Antibodies against purified bovine testicular hyaluronidase were prepared in New Zealand white rabbits. Immunodiffusion, immunoelectrophoresis, and immuno-inhibition studies of the antiserum demonstrated the presence of an antibody specific for bovine sperm hyaluronidase with no cross reactivity to other sperm-associated antigens. Fluorescence microscopy of ejaculated bovine spermatozoa show the enzyme to be limited to the anterior portion of the acrosome with a sharp termination at the rostral border of the equatorial segment of the acrosome. Light microscopic studies with peroxidase-labelled antiserum were similar to the fluorescent findings. Fine structure studies revealed reaction product predominately associated with the matrix of the acrosome cap. Within the acrosome, more intense localisation was observed in the apical densities, while no product was visualised within the equatorial segment. These findings are compatible with the hypothesis that the enzyme functions to facilitate the passage of spermatozoa between cells.
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PMID:The localisation of bovine sperm hyaluronidase. 118 57


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