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:3.6.1.3 (ATPase)
65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several approaches were adopted for the disruption and removal of the tegumental surface from protoscoleces of the horse strain of the hydatid organism, Echinococcus granulosus. The effectiveness of each method and the purity of subsequent microthrix-enriched fractions obtained by differential centrifugation were evaluated by electron microscopy, by the amount of protein released and by the degree of enrichment of surface plasma membrane marker enzymes. Incubation in saponin for 10 min produced the purest microtriche preparation, but in low yield; freeze/thawing, incubation in Triton X-100 for 10 min or in saponin for 20 min produced fractions containing significant amounts of relatively pure microtriches, but mild homogenization was a poor method for surface disruption and subsequent isolation of microtriches. Phosphodiesterase, adenosine triphosphatase (total and ouabain-inhibited), leucine aminopeptidase and glutamyltransferase were active in the protoscoleces but none were enriched in any of the microthrix fractions. In contrast, alkaline phosphatase, acid phosphatase, 5' nucleotidase and maltase were enriched significantly in all of the isolated microtriche preparations, which suggests that these enzymes are predominantly surface membrane bound. The protein profiles of the microthrix-enriched fractions, following SDS-PAGE, were basically similar, although there were some qualitative and quantitative differences in the proteins released by each isolation procedure. Three major PAS-staining components were present in all the preparations and these probably originated from the glycocalyx. One of these PAS-positive components, with an approximate molecular weight of 110 kDa, may be a glycoprotein specific to the horse strain of E. granulosus.
...
PMID:Isolation, fractionation and partial characterization of the tegumental surface from protoscoleces of the hydatid organism, Echinococcus granulosus. 398 50

A new procedure for the rapid isolation of renal cortical brush-border and basolateral membranes from the same homogenate is described. Brush-border membranes isolated using Mg2+-EGTA precipitation were enriched 18-fold for leucine aminopeptidase and had a recovery of 32.5%. Basolateral membrane fractions were isolated using a discontinuous sucrose gradient and showed an enrichment of 10.7-fold and recovery of 12.8% using (Na+,K+)-ATPase as a marker enzyme. Lipid analysis using two-dimensional TLC separation of phospholipids and gas liquid chromatography for cholesterol showed marked differences in the lipid composition of the brush-border and basolateral membranes. The brush-border membrane had increased sphingomyelin, phosphatidylserine, ethanolamine plasmalogens, and an increased cholesterol-to-phospholipid and sphingomyelin-to-phosphatidylcholine ratio compared to the basolateral membrane. The relative turnover of total membrane and individual phospholipid species using a double isotope ratio method was carried out. Phospholipids were labeled with either phosphorus 32 and 33 or acetate (3H, 1-14C). The relative turnover of phospholipid species and cholesterol differed strikingly. Phosphatidylcholine showed a high turnover, phosphatidylethanolamine and phosphatidylinositol had intermediate values and sphingomyelin, phosphatidylserine and cholesterol had low relative turnover rates. The order of phospholipid class relative turnover was independent of the labeled precursor used. The brush-border membrane had a significantly reduced relative turnover rate for total membrane phospholipids, sphingomyelin and cholesterol compared to the basolateral membrane. These data show marked differences in the lipid composition and relative turnover rates of the phospholipid species of the brush-border and basolateral membranes.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Renal cortical brush-border and basolateral membranes: cholesterol and phospholipid composition and relative turnover. 399 20

The virus of transmissible gastroenteritis produced sprue-like lesions in the small intestines of young pigs. These lesions were characterized by villous shortening, fusing and blunting in the jejunum and ileum. There was decreased height of the brush border and morphologic alteration of the villous epithelial cells from simple columnar to a variable cuboidal type. Accompanying these microscopic lesions were histochemical changes characterized by decreased staining intensity of acid phosphatase, alkaline phosphatase, adenosine triphosphatase, leucine aminopeptidase, succinic dehydrogenase and malic dehydrogenase in the affected intestinal mucosa. The clinical nature of transmissible gastroenteritis in the pig together with the histopathologic and histochemical changes may provide a useful experimental model for obtaining additional basic information on enteric disturbances.
...
PMID:Experimental sprue-like small intestinal lesions in pigs. 422 30

1. A technique is described for the removal of subcellular contaminants from intact rat intestinal brush borders, and for the subsequent separation of a microvillus membrane fraction from a fibrillar residue. 2. Increments in invertase activity, microscopic homogeneity and low nucleic acid content indicate that the microvillus plasma membrane has been extensively purified. Multiple membrane preparations have been shown to be highly reproducible with respect to their invertase specific activity, cholesterol content and phospholipid content. Alkaline phosphatase, leucine aminopeptidase, Mg(2+)- and Ca(2+)-dependent adenosine triphosphatase and seven separate disaccharidases were shown to be predominantly confined to the membrane fraction. 3. The fibrillar fraction has been shown to contain approximately 30% of the total protein of purified brush borders, plus most of the residual nucleic acid contaminant. No evidence was found for the localization of any specific enzyme in this fraction.
...
PMID:Rat intestinal microvillus membranes. Purification and biochemical characterization. 429 31

The effect of a single oral dose of endosulfan (5 mg/kg body weight) on the uptake of certain nutrients and brush-border enzymes has been studied in rat intestine. The uptake of glucose and alanine was elevated but that of leucine was decreased in endosulfan-fed rats. There was no change in the uptake of phenylalanine and lysine in insecticide-fed rats. The activities of brush-border sucrase and alkaline phosphatase were considerably increased while the activity of Na+ K+ ATPase was reduced in endosulfan-exposed animals. The leucine aminopeptidase activity was unaffected in pesticide-treated rats. There was a significant decrease in cellular LDH and GOT activities with no change in GPT activity. Neither was there a considerable increase in the cellular glucose-6-phosphatase activity (P less than 0.01) in the pesticide-fed rats. These results suggest that endosulfan toxicity induces certain functional changes in the intestine.
...
PMID:Effect of a single oral dose of endosulfan on intestinal uptake of nutrients and on brush-border enzymes in rats. 618 May 24

It was proposed to test the biocompatibility of a polymeric implant by assaying enzyme activity in the tissue homogenate. Medical grade poly(vinyl chloride) was implanted in rat gluteal muscle and muscle specimens taken from the implanted and non-implanted sites after 7, 14 and 21 days. In the muscle homogenate taken in suitable solvents, the activities of alkaline phosphatase, acid phosphatase, Ca2+ ATPase, leucine aminopeptidase (LAP) and succinic dehydrogenase (SDH) were tested and compared at implanted and non-implanted sites. Increased activity of acid phosphatase, alkaline phosphatase, LAP and Ca2+ ATPase were seen at the implanted site but the SDH activity was reduced. The enzyme activity at both sites was maximum around 14 days and the highest increase in activity at the implant site compared to the control site was observed for alkaline phosphatase and acid phosphatase. After 21 days, the activity decreased gradually. In case of SDH, the inhibition was more after 14 days and gradually decreased after 21 days.
...
PMID:Biocompatibility screening of poly (vinyl chloride) implants. 621 Nov 97

The long term (90 days) effects of medroxyprogesterone acetate (MPA) administration on the digestive and absorptive functions of the small gut have been investigated in female albino rats. The uptake of glucose and amino acids was found to be significantly increased while Ca++ uptake decreased following MPA treatment (35 mg/kg body weight). The observed increase in glucose uptake might be due to carrier mediated transport in enterocytes and not to a change in cell number. The Michaelis constant for glucose uptake was not altered by MPA. Activities of brush border membrane disaccharidases, leucine aminopeptidase and basolateral membrane enzyme Na+, K+-ATPase were significantly increased in response to MPA treatment. It was observed that these biochemical alterations caused by MPA in intestinal digestive and absorptive functions were reversible by 5 weeks after termination of the drug treatment. The action of the drug appears to closely resemble that of known effects of glucocorticoids on intestinal mucosa.
...
PMID:Alterations and reversibility of digestive and absorptive functions of rat intestine following medroxyprogesterone acetate administration. 623 20

High voltage free flow electrophoresis has been applied to the separation of human platelet membranes. After short treatment with neuraminidase at the whole cell level, three membrane vesicle subpopulations have been isolated. Using a surface label (125I-labeled Lens culinaris lectin), the marker enzyme NADH-cytochrome c reductase, and lipid analysis, two of the fractions have been identified as of surface origin and the other consists of intracellular membrane elements. The distribution of adenylate cyclase, leucyl aminopeptidase, 5'-nucleotidase and Ca2+-ATPase has also been investigated, and their usefulness as markers for the different membrane fractions has been evaluated. All three fractions are vesicular but differ in size and character. Their phospholipid and cholesterol contents have been determined, and the cholesterol/phospholipid ratios of the two surface fractions are over twice that of the intracellular membrane, which also has a significantly lower microviscosity as determined by fluorescence polarization using diphenyl hexatriene. The polypeptide profiles from sodium dodecyl sulfate-polyacrylamide gel electrophoresis are particularly distinctive, with actin present in the two surface membrane fractions and absent from the intracellular membranes. Myosin, confirmed by its ATPase characteristics, is almost exclusively localized in one of the surface membrane fractions, and actin-binding protein is a prominent feature of the other.
...
PMID:Characterization of human platelet surface and intracellular membranes isolated by free flow electrophoresis. 626 Jul 85

The effect of a single oral dose of pp'DDT (100 mg/kg body wt.) has been studied on the intestinal uptake of certain nutrients and on brush border enzymes in rats. Intestinal uptake of leucine, and phenylalanine was considerably increased but there was no change in the absorption of glucose and alanine in DDT fed rats, compared to controls. The activities of brush border sucrase, alkaline phosphatase and Na+, K+-ATPase were significantly depressed in pesticide treated animals, but leucine aminopeptidase levels remained unaffected under these conditions. Analysis of the chemical composition of the microvillus membranes revealed a considerable enhancement in total lipids, phospholipids and triglyceride contents of the membranes in DDT exposed rats, but membrane protein, sialic acid and cholesterol fractions did not record any change. 1-14C-acetate incorporation into various lipid classes was studied to explain the observed increase in membrane lipids in DDT exposed animals.
...
PMID:Effect of a single oral dose of pp'DDT on the absorption of nutrients in vitro and on brush border enzymes in rat intestine. 627 79

The effect of vitamin C deficiency on various enzymes of the intestinal epithelium has been studied in guinea pigs. Brush border sucrase and alkaline phosphatase activities were considerably enhanced (p less than 0.001), but leucine aminopeptidase levels were reduced in scorbutic animals compared to the control group. There was essentially no change in the activity of maltase under these conditions. Kinetic studies with sucrase and alkaline phosphatase in control and scorbutic animals revealed that augmentation of the enzyme activities in scurvy is due to enhanced enzyme contents. Lactate dehydrogenase, succinate dehydrogenase, glucose-6-phosphatase and Mg+2 ATPase also exhibited reduced activities in the intestine of vitamin-C-deficient animals. Observed alterations in the activities of intestinal enzymes in scurvy were restored to control levels upon feeding of vitamin C to scorbutic guinea pigs.
...
PMID:Alterations in the activities of intestinal enzymes in vitamin-C-deficient guinea pigs. 627 90


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

---