Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A "free" activity of acidic hydrolases (acidic phosphatase, acidic ribonuclease and cathepsin D) was increased in homogenates of dog heart muscle with simultaneous decrease of the enzymes activity in the fraction enriched by lysosomes, within 4-5 hrs after ligation of the descending ramus of sinister mitral artery. The adenylate cyclase activity and content of c-AMP were decreased as compared with unaffected part of myocardium. The data obtained suggest that the decrease of the c-AMP content in the impaired region caused a labilization of lysosomal membranes and the secretion of acidic hydrolases into cell cytoplasm.
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PMID:[1 of the possible causes of an increase in acid hydrolase activity in homogenates of heart muscle following myocardial infarct]. 19 9

The activity of certain enzymes of energy metabolism (cytochrome c oxidase, citrate synthase, malate dehydrogenase, and lactate dehydrogenase) and of lysosomes (beta-glucuronidase, beta-N-acetylglucosamindase, arylsuphatase, ribonuclease, deoxyribonuclease, acid phosphatase, and cathepsin D) was assayed from m. rectus femoris of mice trained 5 days per week, 1 hr per day for 4 weeks according to 4 different programmes: I. running speed 20 m/min, horizontal track, II. 25 m/min, horizontal track, III. 20 m/min 8 degrees uphill inclination, and IV. 25 m/min 8 degrees uphill inclination. Oxidative capacity increased and anaerobic capacity decreased without distinction between the different traning programmes. Of acid hydrolases assayed the activities of beta-glucuronidase and cathepsin D were increased independently of training intensity. Simultaneous histochemical observations on beta-glucuronidase and arylsulphatase activities in the contralateral m. rectus femoris showed more intense staining in red as compared to white muscle fibres. It is suggested that training affected the red fibres and that the applied level of loading was probably too low to cause major involvement of white fibres.
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PMID:Oxidative and lysosomal capacity in skeletal muscle of mice after endurance training of different intensities. 21 99

The activities of beta-glucuronidase, beta-N-acetylglucosaminidase, arylsulphatase, ribonuclease, p-nitrophenylphosphatase, and malate dehydrogenase together with protein content were assayed from representative mixed (m. rectus femoris), predominantly red (proximal heads of m. vastus lateralis, m.v. medius and m. v. intermedius), and predominantly white (distal head of m. vastus lateralis) muscle homogenates of mice during a two-week period following one single exposure to exhausting intermittent running on a treadmill. The activities of cathepsin D and beta-glycerophosphatase were assayed from mixed muscle only. In all three muscle types, particularly in red muscle, the activities of beta-glucuronidase, beta-N-acetylglucosaminidase, arylsulphatase, and ribonuclease progressively increased between one to five days after the exercise; thereafter the activities began to decrease, being near the conrol values 15 days after the exercise. In mixed muscle, cathepsin D activity increased. No corresponding changes were observed in the activities of acid phosphatases. The time course of the activity changes closely resembled that earlier found to be caused by ischaemia in rabbit muscles. It is tentatively concluded that the two treatments, exhaustive exercise and temporary ischaemia, cause similar cell injuries, and that the lysosomal system involved seems to function similarly in the post-stress recovery of the fibres from these injuries.
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PMID:Acid hydrolase activity in red and white skeletal muscle of mice during a two-week period following exhausting exercise. 21 65

The activity of eight acid hydrolases and two energy metabolism enzymes were assayed from homogenates of predominantly red (proximal heads of m. vastus lateralis, m. vastus medialis, and m. vastus intermedius) and predominantly white (distal head of m. vastus lateralis) skeletal muscle of mice belonging to one of the following groups: 1) sedentary controls, never trained or exhausted; 2) exhausted controls, exhausted once by running on a treadmill 5, 10, or 20 days before killing; 3) trained mice, exercising until killed; 4) exhausted trained mice, exercising until exhausted 5, 10 or 20 days before killing, not exercising during that period; and 5) detrained mice, terminating training 5, 10, or 20 days before killing. In untrained but not in trained animals, exhaustive exercise caused, 5 days afterward, fiber necrosis and a marked increase in the activities of beta-glucuronidase, beta-N-acetylglucosaminidase, arylsulphatase, ribonuclease, deoxyribonuclease, cathepsin D, and cathepsin C, especially in red muscle fibers. Training increased the activities of citrate synthase, beta-glucuronidase, and cathepsin D in both muscle types and those of beta-N-acetylglucosaminidase, arylsulphatase, and cathepsin C in red muscle. Effects of detraining were minor. Exhaustive exercise causes lethal and evidently also sublethal fiber injuries manifesting themselves as an activation of the lysosomal system of muscle fibers 5 days later. Training affects cellular homeostasis by causing an apparent resistance to the damaging effects of exhaustive exercise. Moderately increased hydrolase activities may reflect increased turnover in endurance-trained muscles.
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PMID:Exhaustive exercise, endurance training, and acid hydrolase activity in skeletal muscle. 22 20

To elucidate the metabolic abnormality of musclar dystrophy, 27 kinds of enzyme activity in various organs of control and dystrophic mice were examined. The organs examined included muscle, bone, heart, testis, uterus, spleen, thymus, submaxillary gland, stomach, pancreas, liver, kidney, brain, and lung. The activities of 14 different aminopeptidases, 5 endopeptidases, 4 glycosidases, phosphatase, esterase, and ribonuclease were measured. Most of the enzyme activities were significantly elevated in muscles and bones of dystrophic mice. These organs were similar in their patterns of enzyme abnormality. Among the 14 kinds of aminopeptidase activity studied, the degree of increased activity was greater for the aminopeptidases (AP):Ala-AP, Leu-AP, Met-AP, Phe-AP, Trp-AP, Gly-Pro-Leu-AP. In addition to aminopeptidases, there were significant increases in activities of chymotrypsinlike enzyme, cathepsin C, cathepsin D, several glycosidases and neutral ribonuclease in the muscles of dystrophic mice. Similarly increased enzyme activity was also observed in organs other than muscle and bone. Furthermore, protein content in most organs was higher in dystrophic mice than in those of control mice. These abnormalities were seen in both males and females. The present results suggest that there are extensive abnormalities in the protein metabolism in dystrophic mice. It seems therefore that the therapeutic approach to muscular dystrophy should be studies not only from the well-known abnormality of intramuscular endopeptidases, but from other aspects as well.
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PMID:Various enzyme activities in muscle and other organs of dystrophic mice. 625 14

The present study was performed to investigate the enzymatic changes in dystrophic chickens compared to those of dystrophic mice. The activities of 14 kinds of aminopeptidases, 5 kinds of endopeptidase, 4 kinds of glycosidases, phosphatase, esterase, and ribonuclease were measured in muscles of control and dystrophic chickens. When the enzyme activities were expressed as specific activity per unit weight of organs, only some of them were found to be significantly elevated in dystrophic chickens; e.g., alanine aminopeptidase (Ala-AP), Gly-AP and cathepsin D. On the contrary, the activities of alpha-D-glycosidase, alpha-D-galactosidase and alpha-D-mannosidase were significantly decreased. Muscular protein contents of dystrophic chickens also tended to be lower than those of controls. These observations offer a striking contrast with the one obtained in the study on dystrophic mice. However, when expressed as specific activity per mg protein, many enzyme activities were found to be significantly elevated suggesting an extensive abnormality of metabolism in dystrophic chickens. Among 14 kinds of aminopeptidase activities, highly significant elevations were seen especially in AP-A, AP-B, Gly-AP, Ala-AP, Ser-AP, Pro-AP, Leu-AP, Met-AP and Trp-AP. Interestingly enough, a statistical approach suggested a significant correlation between the aminopeptidase changes of dystrophic chickens with those of dystrophic mice. In addition to aminopeptidases, there were highly significant increases in the activities of cathepsin D, alpha-D-glucosidase, beta-D-galactosidase, alpha-D-mannosidase, esterase and RNase. These results indicate that the intramuscular metabolic abnormality of dystrophic chickens are generally different from but partly resembled with those of dystrophic mice.
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PMID:Intramuscular enzyme abnormalities of dystrophic chickens compared to those of dystrophic mice. 701 13

Acid hydrolase activities in skeletal and cardiac muscle were studied 5, 10 and 20 days after exhaustive intermittent running by untrained and endurance-trained mice. Exhaustion increased the activities of cathepsin D, beta-glucuronidase and ribonuclease, but not that of p-nitrophenylphosphatase in skeletal muscle of untrained mice. Activities were highest on the fifth day after exhaustion and decreased during the following two weeks. More intensive loading produced no changes in acid hydrolytic capacity in skeletal muscle of endurance-trained mice. Acid hydrolase activities in cardiac muscle of both untrained and trained mice were unaffected by exhaustive running. It is suggested that exhaustive running causes both lethal and sublethal hypoxic fiber injuries in the skeletal muscle of untrained mice but not in that of endurance-trained mice or in the cardiac muscle of animals of either group. These injuries manifest themselves as fiber necrosis (lethal) and as increased acid hydrolytic capacity in surviving fibers (sublethal).
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PMID:Acid hydrolase activities in mouse cardiac and skeletal muscle following exhaustive exercise. 719 24

The kinetic properties of UDP-N-acetylglucosamine:lysosomal-enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase) purified to homogeneity from lactating bovine mammary gland have been investigated. GlcNAc-phosphotransferase transferred GlcNAc 1-phosphate from UDP-GlcNAc to the synthetic acceptor alpha-methylmannoside, generating GlcNAc-1-phospho-6-mannose alpha-methyl, the structure of which was confirmed by mass spectroscopy. GlcNAc-phosphotransferase was active between pH 5.7 and 9.3, with optimal activity between pH 6.6 and 7.5. Activity was strictly dependent on Mg2+ or Mn2+. The Km for Mn2+ was 185 microM. The Km for UDP-GlcNAc was 30 microM, and that for alpha-methylmannoside was 63 mM. The enzyme was competitively inhibited by UDP-Glc, with a Ki of 733 microM. The 166-kDa subunit was identified as the catalytic subunit by photoaffinity labeling with azido-[beta-32P]UDP-Glc. Purified GlcNAc-phosphotransferase utilizes the lysosomal enzyme uteroferrin approximately 163-fold more effectively than the non-lysosomal glycoprotein ribonuclease B. Antibodies to GlcNAc-phosphotransferase blocked the transfer to cathepsin D, but not to alpha-methylmannoside, suggesting that protein-protein interactions are required for the efficient utilization of glycoprotein acceptors. These results indicate that the purified bovine GlcNAc-phosphotransferase retains the specificity for lysosomal enzymes as acceptors previously observed with crude preparations.
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PMID:Bovine UDP-N-acetylglucosamine:lysosomal-enzyme N-acetylglucosamine-1-phosphotransferase. II. Enzymatic characterization and identification of the catalytic subunit. 894 Jan 56