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)

The mechanism of albumin biosynthesis was studied in Morris hepatoma 5123tc in vivo and in hepatoma cell suspensions obtained by solubilizing the intercellular matrix with collagenase and hyaluronidase. In the in vivo experiments, L-[-14C]leucine was injected i.v. into rats bearing hepatomas in the muscles of both hind legs. After 14 min, tumors were removed and homogenized. A protein fraction quantitatively precipitable with antialbumin was isolated from the homogenate by acetone fractionation and precipitation with antiserum against serum albumin. This protein fraction was not homogeneous. With the use of 3 consecutive chromatographies on diethylaminoethyl cellulose, a very highly radioactive albumin-like protein could be separated from a large amount of only slightly radioactive albumin. In hepatoma cell suspensions incubated with L-[1-14C]leucine followed by a chase with excess nonradioactive L-leucine, radioactivity was incorporated first into the albumin-like protein and transferred thereafter into albumin, suggesting that albumin was synthesized via the albuminlike protein as precursor. In vivo, 1.8% of newly synthesized hepatoma protein was albumin or its precursor, compared with 1.2% in cell suspensions.
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PMID:Biosynthesis of albumin via a precursor protein in Morris hepatoma 5123tc. 18 40

The mechanism of the biosynthesis of albumin was studied in cell suspensions from rat liver. The cells were prepared by continuous perfusion of the liver in situ with 0.05% collagenase and 0.10% hyaluronidase and incubated under conditions optimized for the incorporation of amino acids into protein. Seven minutes after starting the incubation L-[1-14C]leucine was added, followed after 25 min by a 15 or 30-min chase with an 830-fold excess of non-radioactive L-leucine. Total protein, an albumin-like protein, and albumin were isolated from samples withdrawn immediately of total protein was found to remain constant after addition of the non-radioactive L-leucine, whereas that of the albumin-like protein decreased and that of albumin increased with incubation time. The increase in albumin radioactivity accounted for the decrease in radioactivity of the albumin-like protein, suggesting that the latter is a precursor of albumin. The precursor protein differed from albumin by an oligopeptide extension at the N-terminal end.
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PMID:Synthesis of albumin via a precursor protein in cell suspensions from rat liver. 126 47

The response in perivascular interstitial pressure to water accumulation was measured in air-inflated isolated rabbit lungs. The blood vessels and trachea of isolated lungs were cannulated and the vascular cannulas were connected to a reservoir filled either with a 3% albumin in saline solution (control) or with hyaluronidase in the albumin solution (treated). The lungs were inflated to 5 cmH2O transpulmonary pressure and the vascular reservoir elevated to a height of 7-10 cm above the lung base. The reservoir was suspended by a load cell which measured liquid accumulation in the lung. As the lung gained weight, interstitial pressure was measured by the micropuncture technique in the interstitium surrounding a vein near the hilum of an upper lobe. In control lungs, interstitial pressure increased monotonically with time from a value slightly below 0 cmH2O (pleural pressure) to a value of approx. 3.0 cmH2O by 5 h. In treated lungs, interstitial pressure increased more slowly to a value of approx. 1.5 cmH2O by 5 h. Interstitial compliance, the change in weight gain divided by the change in interstitial pressure, was 1.2 g.(g lobe wt)-1.cmH2O-1 for the control lungs and 2.9 for the treated lungs. A two-compartment electrical analog model representing the perivascular interstitium and alveolar liquid space was developed to simulate the data. The analysis indicated that in the control lungs, perivascular interstitial conductance and compliance were 5-fold and 15-fold smaller than those of the alveolar liquid space, respectively. The slower rise in interstitial pressure with water accumulation in the treated lungs was attributed to an increased compliance of the alveolar liquid space. The effect of hyaluronidase on the alveolar liquid space was to increase its compliance 2.4-fold with little change in its fluid resistance.
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PMID:Effect of hyaluronidase on interstitial pressure response to edema in air-inflated rabbit lung. 143 96

The sequential pattern of perivascular interstitial cuff growth was studied in liquid-inflated rabbit lungs. Degassed isolated lungs were immersed in a saline bath and inflated to 5 cmH2O transpulmonary pressure with a 3% albumin solution or 3% albumin solution containing hyaluronidase. After inflation times varying between 1 and 7 h, the lungs were frozen in liquid N2. From blocks cut from the frozen lungs, interstitial cuff cross-sectional area was measured as a function of vessel size. No cuffs were observed around vessels less than 0.1 mm diam. At all inflation times, only approximately 50% of vessels less than 0.5 mm diam had cuffs, whereas virtually all vessels greater than 0.5 mm diam had cuffs. Cuff-to-vessel area ratio increased with inflation time, reaching a maximum of 1.0-1.4 by 5 h. The time constant of cuff growth was 1 h for the albumin-inflated lungs and was independent of vessel size. The time constant was reduced by 60% in the hyaluronidase-inflated lungs. The time constant for the response in perivascular interstitial pressure measured by micropuncture near the lung hilum was 2.5 h for albumin-inflated lungs and 1.2 h for hyaluronidase-inflated lungs. Electrical analog models were used to fit the experimental data of cuff growth and to determine interstitial liquid resistance. Interstitial resistance for the albumin-inflated rabbit lungs was 2- and 24-fold greater than values estimated previously for sheep and dog lungs, respectively.
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PMID:Effect of hyaluronidase on interstitial cuff and pressure response in liquid-inflated rabbit lung. 159 13

Physiological stimuli induce rapid and unexplained increases in the number of red blood cells within capillaries of skeletal muscle. We hypothesized that such alterations in intracapillary red cell numbers might be due to an undefined interaction between one or more components of blood and the luminal surface of the capillary. This proposition was tested by in situ microperfusion of capillaries with enzymes directed against macromolecules likely to be expressed on the surface of endothelial cells. The instantaneous fractional volume of red blood cells within a capillary (tube hematocrit) was used as an index of a capillary's response to enzyme microperfusion. Five to 8 min of perfusion with enzyme vehicle (0.25% albumin-Ringer solution) produced no significant alteration in capillary tube hematocrit. Perfusion with solutions containing heparinase raised the tube hematocrit at least twofold (P less than 0.05) without a significant change in red cell velocity. Heat-denatured heparinase and other enzymes such as neuraminidase, hyaluronidase, papain, pronase E, and clostripain had no detectable effect on the tube hematocrit (P greater than 0.05). After enzyme treatment, application of adenosine (10(-4) M) or oxygen caused brisk vasomotor responses in arterioles feeding perfused capillary units, but the usual changes in the tube hematocrit were not observed. Thus heparinase treatment results in a sustained elevation in the capillary tube hematocrit and a dissociation of the typical relationship between vasomotor changes and red cell distribution in capillaries. These findings suggest that physiological stimuli which alter the number of red blood cells within capillaries may operate by modifying interactions between plasma and one or more components on the luminal surface of capillaries.
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PMID:Heparinase treatment suggests a role for the endothelial cell glycocalyx in regulation of capillary hematocrit. 231 79

We have examined the proteins associated with the mucous matrix of the rat cumulus oophorus and compared them to the composition of rat serum, follicular fluid, ampullary fluid, and oocyte-cumulus cell extract. The cumulus matrix was dispersed using Streptomyces hyaluronidase, and the proteins were analyzed by high-resolution two-dimensional polyacrylamide gel electrophoresis and compared with proteins of the serum, proestrous follicular fluid, and postovulatory ampullary fluid and extracts of oocytes and cumulus cells. In addition to albumin and transferrin, which were common to all the fluids analyzed, the cumulus material contained many proteins in common with the follicular fluid and the ampullary fluid. However, the protein extract of the cumulus matrix also contained four major proteins not present in the other fluids analyzed. Two of these proteins were acidic and heterogenous in charge and size (MW approximately 81,000 and 100,000). The other two proteins were more basic and occurred at MW approximately 90,000 and 150,000. Our results show that the extracellular matrix of the cumulus contains proteins that are not present in the fluids that surround the oocyte.
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PMID:Identification of extracellular proteins in the rat cumulus oophorus. 232 26

A hyaluronidase-sensitive component of human peritoneal fluid from a patient with Wilms' tumor when injected into rabbits has been shown to suppress the formation of humoral precipitating antibodies to certain major classes of proteins present in the fluid. Furthermore, it has been found that hyaluronic acid, when included with certain test antigens (serum albumin, fetuin) or antigen mixtures (tumor isolates or mixtures of albumin, immunoglobulin G and immunoglobulin M), produces a marked distortion or complete blockage of immunoelectrophoresis precipitin arcs, as well as altered gel chromatography elution profiles. These findings that hyaluronic acid can interfere profoundly with both the elicitation of a complete antibody response and the formation of "normal" patterns of antigen-antibody precipitates in laboratory tests supports the possibility that this polysaccharide may play an immuno-regulatory role by masking potential immunogens. Consideration of the mechanisms for these in vivo and in vitro effects suggests that there may be some common basis in an "excluded volume" property of the hyaluronate, but this does not appear sufficient to explain the complexity and selectivity of the observed phenomena.
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PMID:The selective suppression of immunogenicity by hyaluronic acid. 242 4

The fluid conductivity of albumin solutions of various concentrations relative to that of saline was measured in the interstitium surrounding a short segment of a large (1.5- to 3-mm-diam) blood vessel of an isolated rabbit lung of which air spaces and vasculature were filled with silicon rubber. At a constant driving pressure, the flow of the following solutions was measured sequentially: normal saline and albumin solution (3, 5.5, 8, or 15 g/100 ml saline), hyaluronidase solution (0.02 g/100 ml), and albumin solution (same concentration used before hyaluronidase solution). The albumin-to-saline flow ratios averaged 1.00 +/- 0.23 (SD), 1.01 +/- 0.21, 1.32 +/- 0.63, and 1.54 +/- 0.36 for albumin concentrations of 3, 5.5, 8, and 15 g/100 ml, respectively. These ratios were higher than the corresponding values of 0.88, 0.78, 0.72, and 0.5 expected if the flow of albumin solution were to depend only on fluid viscosity. The flow of dextran and hyaluronan solutions was more viscosity dependent than the flow of albumin solutions. The increased flow of albumin solution could be the result of a reduced excluded volume of albumin caused by collagen and glycosaminoglycans with an increased albumin concentration. The flow of hyaluronidase solution was 24 +/- 22 (SD)-fold (n = 36) larger than the flow of albumin solution. Thus hyaluronan was responsible for most of the hydraulic resistance of the interstitium to bulk flow. After its degradation, the flow of albumin solution became more viscosity dependent. The interaction between plasma proteins and glycosaminoglycans in the pulmonary interstitium could serve to enhance clearance of microvascular filtrate, particularly under conditions of large protein leaks.
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PMID:Effects of albumin, dextran, and hyaluronidase on pulmonary interstitial conductivity. 247 54

The prognostic value of the sperm penetration assay (SPA) using zona-free hamster ova has not been universally accepted. This is partly due to technical problems with the assay, resulting in 5-17% false negative results. The advantage of replacing albumin with defined synthetic polymers in the SPA culture media, increasing the calcium gradient and incorporating potential active tract agents and antioxidants, has been investigated. These studies have resulted in the development of a procedure that has produced no negative results among known fertile donors (n = 55). Application of this technique to a non-specific group of patients with suspected sub-fertility produced a different pattern of sperm penetration compared with the 'standard' SPA in 27% of cases. Improved sperm velocity, motile survival, enhanced hyaluronidase release and rate of acrosome induction were noted using the synthetic media.
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PMID:Assessment of heterospecific zona-free ovum penetration under fully defined conditions. 337 98

Classical techniques for studying modulations of microvascular permeability have a time resolution of minutes. A newly developed method allows continuous measurement of the electrical resistance of the microvascular membrane in vivo (Olesen & Crone 1983). The technique exploits microelectrodes impaled into the vascular lumen and is based on cable analysis of the vessel. It was applied to venules on the surface of the frog brain to test the effect on microvascular permeability of a wide variety of substances. The following agents increased ionic permeability reversibly within seconds: 5-hydroxytryptamine, bradykinin, ATP, ADP, AMP, phospholipase A2, arachidonic acid, leukotriene C4, oxygen-derived free radicals, ionophore A23187, and unbound Evans blue dye. An irreversible permeability increase was induced by protamine sulphate, neuraminidase, trypsin, melittin, and snake venoms from Crotalus durissus terrificus and Bothrops atrox. The following substances were without effect within an administration period of 5 min: histamine, epinephrine, putrescine, angiotensin II, vasoactive intestinal polypeptide (VIP), substance P, neurotensin, vasopressin, adenosine, PGE2, PGF2 alpha, prostacyclin (PGI2), leukotriene B4, albumin, heparin, plant cytokinins, hyaluronidase, thrombin, wasp venom. Variations in pH between 5.1 and 8.6 did not change permeability. Three conclusions are drawn from the observations: (1) the permeability of cerebral microvessels can be modulated by specific agents, (2) the agents induced changes in the endothelium within a few seconds, and (3) the rapid permeability increase induced by inflammatory mediators was less than two-fold and reversible within minutes.
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PMID:Substances that rapidly augment ionic conductance of endothelium in cerebral venules. 348 16


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