Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
Disease
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Drug
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Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
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Query: EC:3.6.1.3 (
ATPase
)
65,361
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effects of amphotericin B drug containing sodium deoxycholate (DOC) and those of DOC and nistatin on the activities of Na+, K+-
ATPase
and
5'-nucleotidase
of canine kidney plasma membranes were studied. It was found that the activities of Na+, K+-
ATPase
and
5'-nucleotidase
were markedly inhibited only after intravenous injection of amphotericin B, whereas the other agents tested caused no changes in the enzyme activities. Similar results were obtained in vitro. In the presence of amphotericin B the activity of Na+, K+-
ATPase
was noticeably inhibited already at the antibiotic concentration of 0,1 mkg per mg of membrane protein. It was found that the injection of amphotericin B, DOC and nistatin did not qualitatively or quantitatively affect the phospholipid composition of the plasma membranes. This is indicative of the lack of correlation between the enzyme activities and changes in the phospholipid composition of the plasma membranes under effects of amphotericin B. The pyrimidine derivative--amygluracyl--markedly removes the inhibiting effect of amphotericin B on the enzyme activity of plasma membranes.
...
PMID:[Activities of enzymes from canine kidney plasma membranes under effects of polyene antibiotics in vivo and in vitro]. 21 53
Fractions enriched in hCG-binding activity were prepared by differential rate centrifugation of superovulated rat ovarian homogenates and were applied to continuous sucrose density gradients (20-55%). After centrifugation at 63,000 x gav for 3.5 h, fractions of each gradient were collected and assayed for a range of marker enzyme activities characteristic of surface membranes and subcellular organelles. Mitochondria, lysosomes, and rough and smooth endoplasmic reticulum membranes accumulated in the gradient between 38-41% sucrose (1.165-1.180 g/cm3). Nuclei passed through the gradient. However, the various surface membrane markers concentrated in two distinct regions of the gradient. Alkaline phosphatase, phosphodiesterase, (Na+ + K+)
ATPase
I, and hCG-binding activity concentrated at 29-32% sucrose (1.120-1.135 g/cm3), whereas
5'-nucleotidase
, Mg2+-dependent
ATPase
, and adenylate cyclase activities (and minor peaks of hCG-binding and phosphodiesterase activities) were enriched at 36-38% sucrose (1.16-1.17 g/cm3). A second
ATPase
, [(Na+ + K+)ATPase II], was also observed in this region of the gradient, which could be distinguished from (Na+ + K+)
ATPase
I of the light membrane fraction by its sensitivity to the Ca2+-chelating agent, ethylene glycol bis-(aminoethyl)tetraacetic acid (EGTA). The kinetics of binding of radioiodinated hCG to the gonadotropin receptors of the light and heavy membrane fractions were very similar. It is suggested that fractionation of superovulated rat ovaries yields two distinct populations of surface membrane material which have distinct densities and marker enzyme profiles. Furthermore, in contrast to the heavy membrane fraction, light membranes seem to possess considerable amounts of hCG receptor activity but very little adenylate cyclase.
...
PMID:Interactions of gonadotropins with corpus luteum membranes. II. The identification of two distinct surface membrane fractions from superovulated rat ovaries. 21 57
Plasma membranes were obtained from a homogeneous population of rabbit red blood cells at different maturation periods. Minor modifications in membrane proteins and membrane phospholipids and significant decreases in membrane glycoproteins and total lipids were observed with the age of the cell. The ouabain inhibited (Na+K+)-
ATPase
and the adenylate cyclase decreased with maturation but acetylcholinesterase and
5'-nucleotidase
remained almost unchanged. The apparent activation energy of the
ATPase
increased with maturation. The results indicate that structural and functional modifications of the plasma membrane occur concomitantly with the ageing processes of the red cell.
...
PMID:Studies of the plasma membrane during maturation of the mammalian erythrocyte. 21 11
The activities of dTMP kinase (ATP-deoxythymidine monophosphate phosphotransferase, EC 2.7.4.9),
5'-nucleotidase
(5'-ribonucleoside phosphohydrolase, EC 3.1.3.5), adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4), AMP deaminase (AMP aminohydrolase, EC 3.5.3.6) and ATP-(Mg2+)-ase (
ATP phosphohydrolase
,
EC 3.6.1.3
) were assayed in mitochondria of normal and regenerating rat liver. In regenerating mitochondria, the dTMP kinase activity increased 20 times,
5'-nucleotidase
(5'Nase) activity for dTMP diminished by 65% and its activity for other nucleoside monophosphates did not change; adenosine deaminase activity for adenosine (AR) increased by 40%, but for deoxyadenosine (AdR) decreased by 70%. AMP deaminase and ATP-(Mg2+)-ase activities behaved similarly in mitochondria from regenerating liver, decreasing by 70 and 64% respectively. The changes of the amount of dTMP in mitochondria depend on enzyme activities which regulate the AdR concentration.
...
PMID:Relationship between 5'-nucleotidase, adenosine deaminase, AMP deaminase, ATP-(Mg2+)-ase activities and dTMP kinase activity in rat liver mitochondria. 22 41
A method is described for isolation of plasmatic membranes of rat fatty cells immediately from fatty tissue without the treatment with collagenase. Homogenization of fatty tissue was carried out in large volumes of buffered sucrose and EDTA at room temperature followed by sucrose density gradient centrifugation. The preparations obtained exhibited high specific activity of the marker enzyme of plasmatic membranes [
5'-nucleotidase
and K+, Na+-
ATPase
], as well as high ability for specific binding of insulin.
...
PMID:[Isolation of the plasma membranes of fat cells without using collagenase]. 22 73
Certain phosphatases have been localized by histochemical techniques in various tissues of a pigeon cestode, Raillietina (Raillietina) johri. Acid phosphatase (AcPase), alkaline phosphatase (AlPase) and
adenosine triphosphatase
(
ATPase
) were present in almost all structures: tegument; subtegumental muscles; subtegumental cells; excretory canal; testes; sperm ductules; vas deferens; cirrus sac; cirrus; ovary; receptaculum seminis; vagina; vitelline gland cells; oocytes; uterus; embryonated eggs. AlPase was absent in parenchyma, spermatocytes, spermatids and spermatozoa. AlPase activity was more intense in the tegument of mature gravid proglottides. AcPase and
ATPase
were visualized in various stages of spermatogenesis of the parasite.
ATPase
activity was also observed in chromosomes.
5'-nucleotidase
(AMPase) activity was restricted to embryonated eggs only. Functional significance of these phosphatases is discussed.
...
PMID:Histochemical studies on Raillietina (Raillietina) johri (Cestoda: Davaineidae). I. Nonspecific and specific phosphatases. 22 30
A procedure was developed for the isolation of cardiac sarcolemmal vesicles. These vesicles are enriched about ten-fold (with respect to the tissue homogenate) in K+-stimulated p-nitrophenylphosphatase, (Na+ + K+)-
ATPase
,
5'-nucleotidase
activities and sialic acid content, all of which are believed to be components of the sarcolemma. The sarcolemma of tissue culture cardiac cells were radioiodinated and the distribution of this radioiodine paralleled the distribution of the other membrane markers above. There was very little contamination of the sarcolemmal fraction by sarcoplasmic reticulum (as judged by Ca2+-ATPase and glucose-6-phosphatase activities) or inner mitochondrial membranes (as judged by succinate dehydrogenase activity). There may, however, be some contamination by outer mitochondrial membranes (as judged by monoamine oxidase and rotenone-insensitive NADH cytochrome c reductase activities) which have rarely been monitored in cardiac sarcolemmal preparations. The purity of this preparation is good when compared with other cardiac sarcolemmal preparations. This preparation should be very useful in studying the roles of the cardiac sarcolemma (e.g. in excitation contraction coupling and Ca2+ binding).
...
PMID:Isolation and characterization of cardiac sarcolemma. 22 23
A membrane fraction with sarcolemmal properties was purified from the smooth muscle layers (myometrium) of rat uterus by successive differential and equilibrium centrifugation in sucrose. The putative sarcolemmal fraction was identified by iodination with [125I]iodosulfanilic acid, had an equilibrium density of 1.15, and was enriched in enzyme activities usually associated with the plasma membrane including
5'-nucleotidase
(EC 3.1.3.5) and (Na+ + K+)
ATPase
(
EC 3.6.1.3
). These membranes were free of mitochondrial or nuclear membrane contamination, suggesting the relative enrichment of sarcolemmal membranes in the fraction. Proteins of the membranes were heterogeneous with respect to molecular weight, but only a few were labelled when intact muscle was radioiodinated. Uniform resistance of sarcolemmal proteins to trypsin digestion and salt extraction suggested many are tightly bound or intrinsic membrane proteins and was a further indication of the homogeneity of membranes in this fraction.
...
PMID:Smooth muscle cell sarcolemma. Purification and properties of plasma membranes from the rat uterus. 22 28
Liver plasma membrane (LPM) NaK-
ATPase
activity, LPM fluidity, and bile acid-independent flow (BAIF) were studied in rats pretreated with one of five experimental agents. Compared with controls, BAIF was increased 24.6% by thyroid hormone and 34.4% by phenobarbital, decreased by ethinyl estradiol, but unchanged by propylene glycol and cortisone acetate. Parallel to the observed changes in BAIF, NaK-
ATPase
activity also was increased by thyroid hormone (40.8%) and decreased by ethinyl estradiol (26.2%). In contrast, NaK-
ATPase
activity failed to increase after phenobarbital but did increase 36% after propylene glycol and 34.8% after cortisone acetate. Thus BAIF and NaK-
ATPase
activity did not always change in parallel. The NaK-
ATPase
K(m) for ATP was not affected by any of these agents.LPM fluidity, measured by fluorescence polarization using the probe 1,6-diphenyl-1,3,5-hexatriene, was found to be increased by propylene glycol, thyroid hormone, and cortisone acetate, decreased by ethinyl estradiol, and unaffected by phenobarbital. Thus in these cases, induced changes in LPM fluidity paralleled those in NaK-
ATPase
activity. In no case did Mg-
ATPase
or
5'-nucleotidase
activities change in the same direction as NaK-
ATPase
, and the activity of neither of these enzymes correlated with LPM fluidity, thus indicating the selective nature of the changes in LPM enzyme activity caused by the agents. These findings indicate that LPM fluidity correlates with NaK-
ATPase
activity and may influence the activity of this enzyme. However, the nature of the role of LPM NaK-
ATPase
in bile secretion is uncertain and needs further study.
...
PMID:Studies of relationship among bile flow, liver plasma membrane NaK-ATPase, and membrane microviscosity in the rat. 22 37
The hepatotoxicity of CPZ was studied in the isolated perfused rat liver in order to more closely define possible mechanisms of phenothiazine-induced cholestasis. Perfusate concentrations of CPZ were increased from 5 x 10(-6) M to 5 x 10(-4) M until bile secretion was significantly inhibited. Measurements were then made of determinants of bile secretory function, including the magnitude of lobar distribution of perfusate flow, BAIF, and liver plasma membrane enzyme activity, Na+,K+-
ATPase
, Mg++-
ATPase
and
5'-nucleotidase
. BAIF diminished significantly from control values of 1.76 +/- 0.07 microliter min-1gm-1 of liver to 1.34 +/- 0.15 and 0.80 +/- 0.09 following 2.5 and 5 x 10(-4) M CPZ, respectively. Perfusate flow also diminished from 5.64 +/- 0.44 to 1.24 +/- 0.12 ml min-1 gm-1 of liver 20 min following 5 x 10(-4) M CPZ and was associated with reduced flow to peripheral areas of the hepatic lobes as demonstrated by Tc-HAM. By 30 min, perfusate flow had returned to baseline values. CPZ also transiently diminished the excretion of bile acids in livers receiving a constant infusion of 40 mumol hr-1 sodium taurocholate. Defects in hepatic perfusion could not account entirely for the impairment in BAIF, since comparable mechanical restriction of perfusate flow in controls only diminished BAIF to 1.49 +/- 0.08 microliter min-1gm-1 of liver. CPZ signofocamt;u rediced tje secofoc actovotu pf Mg++-
ATPase
and
5'-nucleotidase
but did not affect Na+,K+-
ATPase
in liver plasma membrane isolated 20 min after 5 x 10(-4) M CPZ. CPZ also resulted in a profound shift in the recovery of protein in isolated liver plasma membrane fractions from the light (density = 1.16) to heavier (density = 1.18) fractions. These findings, together with previous observations demonstrating alterations in hepatic ultrastructure, indicate that CPZ interacts in a complex manner with hepatocyte plasma and cytoplasmic membrane components and suggest that these drug-membrane interactions independently result in diminished hepatic perfusion, impairment of bile acid excretion, and inhibition of bile acid-independent bile secretion.
...
PMID:Effect of chlorpromazine on hepatic perfusion and bile secretory function in the isolated perfused rat liver. 22 76
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