Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Autografts and homografts of full thickness skin were made on a hind limb of rabbits. During the following days the appearance and histological changes of the grafts were studied; the lymph flow from the limb, and the enzyme activities in the supernatant and cell pellet of the lymph after centrifugation were determined, as well as the enzyme activities in the graft roof and the underlying host tissue. It was further examined whether a lymphatic and vascular connexion occurred between graft and host tissue.2. During the first 5 days the grafts changed from pale blue to bright pink, became swollen, soft and had a mild cellular inflammatory exudate. Autografts then became pale, took on the appearance of normal skin with the inflammatory changes subsiding, whereas homografts became firm, showed heavy mononuclear cell infiltration, had a blotchy purple appearance due to thrombosis and haemorrhage, developed widespread necrosis and changed into a black hard scab which was eventually shed. With high dose homografts (6-8 grafts) these changes occurred 1-2 days earlier than with low dose (2-4) grafts.3. The flow of lymph increased during the first 5 days after grafting, then returned to normal with autografts but remained increased with homografts.4. In the supernatant of the lymph the activities of LDH and beta-glucuronidase did not change during the first 5 days but activities of cathepsin, acid phosphatase, GOT and GPT increased. With the autografts the increase in the activities of these four enzymes then subsided, but with the homografts they increased further and there was an increase in the activities of LDH and beta-glucuronidase, even greater than in those of the other four enzymes.5. In the cell pellets of the lymph the activities of the six enzymes did not increase during the first 5 days; with homografts, but not with autografts, they then increased. These increases occurred even though the cell count in the pellet remained unchanged. Thus some of the lymphocytes must have become ;activated' to contain higher enzyme activities.6. The enzyme activities in the roof tissue did not parallel those in lymph. They did not change during the first three days. During the following three days the activities of acid phosphatase, LDH, beta-glucuronidase and cathepsin increased, but not those of GOT and GPT which remained low. From then onwards the behaviour was different with auto- and homografts. With autografts only the activity of acid phosphatase continued to increase, those of LDH, beta-glucuronidase and cathepsin decreased and those of GOT and GPT remained low. With homografts the activities of LDH, beta-glucuronidase and cathepsin continued to increase and became even greater than in the supernatant of lymph, whereas the activities of acid phosphatase, GOT and GPT, remained low.7. In the bed tissue the activities of all six enzymes increased during the first 3 days after grafting, then the activities of GOT and GPT returned towards normal but those of the other four increased further. The only difference between auto- and homografts was that the increase in beta-glucuronidase and LDH activity was much greater with homografts.8. Lymph drainage became established with autografts on day 5 or 6 and then persisted. With homografts the dosage of grafts influenced the result. With low dosage (2-4 grafts) lymph drainage became established in a small percentage of the experiments, also on day 5 or 6, but it persisted for 2-3 days only. With high dosage, no lymph drainage became established. However, when the onset of rejection was delayed by treatment with cyclophosphamide lymph drainage became established also with high dosage homografts.9. Vascularization of the grafts was established on day 3 or 4, and persisted in autografts. In homografts a vascular shut down occurred at about the time of onset of rejection. It therefore occurred later with low than with high dosage and with high dosage on treatment with cyclophosphamide.10. It is concluded that the absence of lymph drainage from homografts is the cause of the small magnitude of increases in enzyme activities of lymph collected during and after their rejection. The increase results from ;activated' small lymphocytes which infiltrate the graft bed and junctional tissue and subsequently undergo necrosis, and that the establishment of a lymphatic connexion between the graft and host tissue is not a prerequisite for rejection.
...
PMID:Lymph flow and changes in intracellular enzymes during healing and rejection of rabbit skin grafts. 494 93

The importance of granular (lysosomal) enzymes from neutrophils in producing the tissue damage of acute inflammation has been suggested by much indirect and some direct evidence. This study has investigated the kinetics of release and subsequent fate of granular enzymes from phagocytizing human leukocytes The following observations are made: (a) During phagocytosis, the granular enzyme lysozyme is released from leukocytes into the extracellular medium. (b) Release of lysozyme increases as phagocytic challenge increases, but attains a maximum. (c) Release of lysozyme accompanies phagocytosis and is not a delayed event. (d) The lack of release of a nongranular enzyme, lactic dehydrogenase, indicates that cell damage is not a necessary condition of enzyme release. (e) Like lysozyme, beta-glucuronidase is released from phagocytizing leukocytes. Acid alpha-naphthyl phosphatase and cathepsin also appear to be released, but are not found in appreciable amounts in the extracellular medium, in part because of their lability in solution. These results support the concept that extracellular release of granular enzymes may be a useful secretory function of inflammatory leukocytes which becomes damaging to the host in certain circumstances.
...
PMID:The mobilization and extracellular release of granular enzymes from human leukocytes during phagocytosis. 502 60

Mouse mononuclear phagocytes cultivated in 50 per cent newborn calf serum medium pinocytize actively and form large numbers of phase-dense granules as well as three hydrolytic enzymes. When such cells are then placed in 1 per cent newborn calf serum they illustrate (a) a low level of pinocytic activity, (b) a shrinkage in granule size, and (c) a loss in cell protein, acid phosphatase, beta-glucuronidase, and cathepsin. Examination of the extracellular medium revealed no detectable hydrolase activity. The reintroduction of cells into high levels of serum again resulted in granule and enzyme formation. Cells rapidly incorporated fluorescein-conjugated calf serum proteins into the phase-dense granules. The fluorescence of labeled granules was lost during an 18 hour period in non-fluorescein-containing medium. Crystalline egg white lysozyme was concentrated in the macrophages. Approximately 80 per cent of the cell-associated enzyme was lost during a 24 hour washout period in either 1 or 50 per cent serum medium. No enzymatic activity could be recovered in the medium. Colloidal gold was taken up and concentrated in macrophage granules. Quantitative assays revealed this particle to be conserved during a 24 hour washout period.
...
PMID:The in vitro differentiation of mononuclear phagocytes. 3. The reversibility of granule and hydrolytic enzyme formation and the turnover of granule constituents. 532 Mar 3

1. Homogenates of guinea-pig polymorphonuclear leucocytes were separated by differential centrifugation into six particulate fractions and a soluble fraction. 2. The distributions in these fractions of protein, DNA, succinate dehydrogenase, beta-glucuronidase, peroxidase, alkaline phosphatase, acid phosphatase (against p-nitrophenyl phosphate and beta-glycerophosphate), cathepsin, and catalase were compared. 3. Almost all of the DNA sedimented in the first two pellets, indicating that the nuclei were relatively intact. 4. The four hydrolases and peroxidase showed different distribution patterns, although these activities were previously reported to be localized mainly in the single ;granule' fraction isolated from leucocytes. 5. The particles containing peroxidase, acid phosphatase and alkaline phosphatase all exhibited latency. Maximum activity for each enzyme was obtained at roughly similar concentrations of Triton X-100. 6. The acid phosphatase of these cells was distributed between two populations of particles that differed in both sedimentation characteristics and density. The acid phosphatase(s) of the two populations showed slightly different substrate specificities. This bimodal distribution was not an artifact of the procedure used to elicit the cells. 7. Catalase was recovered almost entirely in the soluble fraction and showed no latency in freshly prepared homogenates. No urate oxidase was detected. 8. We conclude that the ;granule' fraction of the polymorphonuclear leucocyte, as isolated by previous workers, contains at least three, probably more, populations of particles with different enzyme contents, and that these cells probably do not contain peroxisomes.
...
PMID:The distributions of some granule-associated enzymes in guinea-pig polymorphonuclear leucocytes. 541 96

Rat mammary tumours induced by 7,12-dimethylbenz[a]anthracene can undergo repeated growth and regression during successive pregnancies. In a 10-day period after birth about half of the tumours regressed 50% or more. The concentrations of the lysosomal enzymes increased in regressing mammary tumours to the following multiples of the initial values: beta-glucuronidase, 7.7; beta-galactosidase, 3.9; cathepsin, 2.9; acid ribonuclease, 2.1; arylsulphatase A, 1.5; acid phosphatase, 1.4. In contrast, several non-lysosomal enzymes failed to increase. Activities in the post-partum uterus increased to the following multiples of the initial values: beta-glucuronidase, 5.8; cathepsin, 5.5; acid ribonuclease, 4.3; beta-galactosidase, 2.2; acid phosphatase, 1.8. Arylsulphatase A in the post-partum uterus decreased significantly, suggesting a non-lysosomal distribution or a special function related to pregnancy. No other significant changes were observed in the lysosomal or non-lysosomal enzymes in the hormone-independent liver or hormone-dependent normal mammary gland. The ratio of free to bound arylsulphatase A and acid ribonuclease decreased slightly 1-3 days after birth because of problems in homogenizing the tumours. At days 4-8, however, there was a dramatic increase in the ratio of the free to bound activities. The results can be explained in terms of the lysosomal theory of intracellular digestion.
...
PMID:Lysosomal enzyme changes in growing and regressing mammary tumours. 576 57

1. The rat uterus contains acid cathepsin, beta-glucuronidase, beta-galactosidase, acid phosphatase and deoxyribonuclease II at concentrations comparable with those found in liver. Two non-hydrolytic uterine enzymes, cytochrome c oxidase and aspartate aminotransferase, display only 2-6% of the activity found in liver. 2. The concentrations of acid cathepsin and beta-glucuronidase are significantly decreased in pregnancy and increase 3-4-fold during post-partum involution. 3. The concentrations of beta-galactosidase and acid phosphatase are not decreased in pregnancy and increase only 2-3-fold during involution. 4. The concentrations of these four acid hydrolases increase linearly during the first 4 days post partum and reach their peak values at the same time that wet weight and collagen content fall to their lowest point. 5. The concentration of deoxyribonuclease is depressed in pregnancy but does not rise above normal in the post-partum period. 6. Only a small proportion of each hydrolytic activity can be isolated in the mitochondrial-lysosomal fraction of sucrose homogenates of the rat uterus. This proportion increases during involution. However, the extensive mitochondrial rupture occurring during homogenization indicates that the technique is probably too harsh to obtain a true measure of the proportion of lysosomes present in the intact tissue. 7. There are no significant changes in either the concentration or subcellular distribution of the five acid hydrolases in the livers of the experimental rats during pregnancy or involution. In each case the largest proportion of the activity is found in the mitochondrial-lysosomal fraction of liver homogenates. 8. The results are interpreted in terms of the lysosomal theory of intracellular digestion.
...
PMID:Acid hydrolases of the rat uterus in relation to pregnancy, post-partum involution and collagen breakdown. 589 45

1. An homogenate of bovine adrenal medulla contains significant amounts of six acid hydrolases: acid ribonuclease, acid deoxyribonuclease, cathepsin, acid phosphatase, beta-glucuronidase and arylsulphatase. Most of the activity of each enzyme could be sedimented in the large-granule fraction at 242,000 g-min.2. Differential centrifugation indicated the presence of three populations of particles, which sedimented at slightly different rates; these are, in order of decreasing sedimentation rate, mitochondria, particles containing the acid hydrolases, and chromaffin granules.3. The three types of particle could be separated by ultracentrifuging the large-granule fraction in a sucrose density gradient. Most of the activity of each hydrolase was recovered in a layer intermediate between those formed by mitochondria and chromaffin granules.4. The large-granule fraction therefore contains particles which are defined by their enzyme content as lysosomes.5. Highly purified chromaffin granules, containing less than 5% of the activity of each acid hydrolase, were obtained from the gradient.
...
PMID:The localization of lysosomal enzymes in chromaffin tissue. 594 47

1. Acid phosphatase, cathepsin and beta-glucuronidase are released from rat-liver lysosomes by irradiation in vitro. Enzyme release is detectable after a dose of 1krad and increases with dose up to 100krads. 2. Maximum radiation effects were observed when the lysosomes were kept for 20hr. at 4 degrees or 20 degrees after irradiation. 3. An atmosphere of nitrogen considerably decreases enzyme release from lysosomes. 4. Enzyme release is enhanced by ascorbic acid and decreased by vitamin E. 5. Irradiation causes formation of lipid peroxides in lysosomes, and enzyme release increases with lipid peroxide formation. 6. It is suggested that lipid peroxide formation leads to rupture of the lysosome membrane and allows release of the contained hydrolytic enzymes.
...
PMID:Release of enzymes from lysosomes by irradiation and the relation of lipid peroxide formation to enzyme release. 596 62

1. Two acid phosphatases (beta-glycerophosphatase and phenylphosphatase), acid beta-glucuronidase and cathepsin were demonstrated in the 0.25m-sucrose homogenates from whole calf thyroid tissue and from isolated calf thyroid cells. 2. The main kinetic characters of these enzymes were studied. 3. All these acid hydrolases are partially sedimentable and display a latency that is unmasked by treatment with Triton X-100 and on dilution in hypo-osmotic media. It is concluded that these acid hydrolases belong to the lysosomes.
...
PMID:Lysosomal hydrolases in calf thyroid. 596 51

Whole isolated rat glomeruli (WG) were incubated with bacterial collagenase to separate epithelial cells (EC) from the cores of glomerular tufts (GC), which consisted of mesangial and endothelial cells, as demonstrated by electron microscopy. Lysates of WG, EC, and GC and of renal tubules were prepared by hypo-osmotic shock and freeze-thawing. Activities of the following acidic lysosomal hydrolases were measured: acid phosphatase, beta-glucuronidase, cathepsin-D, non-specific esterase, and aryl sulfatases A and B. The glomerular cell preparations showed activities of all studied enzymes. GC had higher activities than EC, save for nonspecific esterase. Studies of the recovery of acid phosphatase and beta-glucuronidase revealed that approximately 2/3 of the hydrolase activities present in WG was still measureable after collagenase treatment and that the bulk of this was found in the GC lysates. These findings demonstrate that the rat glomerulus and its cell components have considerable biochemical activities of acidic hydrolytic enzymes. These appear to be most prominent in the combined mesangial and endothelial cells of the GC components.
...
PMID:Lysosomal enzymes in glomerular cells of the rat. 628 26


<< Previous 1 2 3 4 5 6 7 Next >>

---