Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationship between adenylate cyclase activity in the synaptic membrane fraction (M1) of rat brain and lipid peroxidation of these membranes was examined. In the presence of 5 mM dithiothreitol (DTT), 1 to 10 microM Fe/+ activated adenylate cyclase 2- to 4-fold. Of several metal ions, Fe2+ was the most effective. Other enzymes in M1, such as Mg2+-ATPase, (Na+-K+)-ATPase, 5'-nucleotidase, acetylcholinesterase, and phosphodiesterase, were not activated by Fe2+ plus DTT. Activation of adenylate cyclase by Fe2+ plus DTT was accompanied by production of malondialdehyde, a product of lipid peroxidation. Formation of malondialdehyde was completely parallel with enzyme activation. Ascorbic acid or a NADPH system also stimulated enzyme activity and caused lipid peroxidation. Activation of the enzyme and lipid peroxidation induced by Fe2+ plus DTT, ascorbic acid, or NADPH was completely prevented by simultaneous addition of N,N'-diphenyl-p-phenylenediamine, an inhibitor of lipid peroxidation. This inhibitor also prevented the decrease in turbidity of the enzyme preparation induced by Fe2+ plus DTT. The stimulatory effects of NaF, guanylyl-5'-imidodiphosphate and calmodulin, respectively, and that of Fe2+ plus DTT on the enzyme activity were additive. Activation of adenylate cyclase by Fe2+ plus DTT was only observed in brain synaptic membranes, not in erythrocyte ghosts, liver plasma membranes, or cardiac sarcolemma. These results indicate that lipid peroxidation of synaptic membranes was accompanied by specific stimulation of adenylate cyclase activity.
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PMID:Activation of adenylate cyclase of rat brain by lipid peroxidation. 721 51

Ultrastructural localization of adenylate cyclase (AC) activity was investigated in suspensions of unfixed isolated rat thymocytes using a medium containing 0.6 mM 5'-adenylylimidodiphosphate (AMP-PNP) as a substrate, 10 mM MgSO4 as an activator, 5 mM theophylline as an inhibitor of 3' 5'-AMP-phosphodiesterase and 2 mm lead nitrate as a capturing agent. AC activity was demonstrated in plasma membrane, perinuclear space, endoplasmic reticulum, Golgi complex, centriole microtubules and mitochondria. AC was activated with 10(-4) M adrenaline in the presence of 5'-guanylylimido-diphosphate (GMP-PNP) as well as with 10(-2) M NaF. In the cells incubated in a medium devoid of theophylline and containing 5'-AMP instead of AMP-PNP, 5'-nucleotidase activity was observed in the same cell structures as AC activity, Hydrolysis of 5'-AMP in the nucleus was much stronger than that of AMP-PNP. 10 mM NaF markedly inhibited hydrolysis of 5'-AMP in all cell structures. No staining was observed with 2 mM beta -glycerophosphate as a substrate. Incubation of unfixed thymocytes in media containing AMP-PNP, 5'-AMP or p-nitrophenyl phosphate, but not beta -glycerophosphate, induced both in the nucleus and in the cytoplasm in some cells an appearance of a transitory reticular formation consisting of about 303nm thick strands which could penetrate the nuclear envelope and plasma membrane and form connections with adjacent cells. The transitory reticular formation seems to belong to the cytoskeleton and to be involved in cell aggregation.
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PMID:Ultracytochemical localization of adenylate cyclase activity in rat thymocytes. 729 93

The activities of adenylate cyclase (AC) and 5'-nucleotidase (NT) were studied in the limbic (amygdala, hippocampus) and sensorimotor (cortex, striatum) brain structures of three rat groups: control (without training), not well and well learning to perform movements with pushing the operandum. It was found, that after training the activity of AC was decreased in all structures studied. Moreover, in the cortex and the striatum the decrease was more pronounced in the group of well learning rats, while in the amygdala--in not well learning ones. The activity of NT in all brain structures, excepting the striatum, was more significantly decreased in the rats with low ability to learn the movements with prolonged pushing. Only in the striatum the increase of NT activity (initially the lowest in the control animals--1.0 +/- 0.04 microgram P(i)/mg protein/min) up to 1.3 +/- 0.1 in not well and up to 2.0 +/- 0.1 in well learning animals was found. The interhemispheric [correction of intrahemispheric] asymmetry of AC activity in the cortex and of NT in the hippocampus was revealed. Thus, the changes of the activity of the enzymes, participating in the biogenesis of adenosine (NT) and c-AMP (AC) are different in the limbic and sensorimotor structures dependently on learning ability of rats. The increase of NT activity after learning only in the striatum could reflect a specific role of purinergic system of this brain structure in the regulation of sensory controlled movements.
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PMID:[Adenylate cyclase and 5'-nucleotidase activities in the sensorimotor and limbic structures of the rat brain after training in a manipulative skill]. 748 13

Human foreskins were examined for enzyme-histochemical staining of microvessels using guanylate cyclase, an enzyme similar to adenylate cyclase. Like 5'-nucleotidase (which hydrolyzes 5'-adenosine monophosphate to adenosine), and adenylate cyclase (which converts adenosine triphosphate to cyclic AMP), guanylate cyclase selectively stains positive for lymphatic capillaries and therefore may be another useful histochemical marker to differentiate dermal lymph from blood capillaries.
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PMID:Enzyme-histochemical staining of dermal lymphatic capillaries by guanylate cyclase. 751 10

The activity of acetylcholinesterase (AChE), 5'-nucleotidase (NT) and adenylate cyclase (AC) were studied in sensomotor cortex and neostriatum (NS) from right and left hemispheres of control and experimental rats, trained to perform food reaching with pushing on operant by preferable forepaw. The levels of summarized bilateral activity of NT as well as of AC were found to be similar in both studied structures of control rats, while the activity of AChE was higher in NS than in cortex. In trained rats the activity of AC was decreased both in cortex and NS, the activity of NT was decreased in cortex and increased in NS, AChE being not changed when compared with control. The bilateral values of enzyme activities in well and badly learning rats were significantly different. Meanwhile, when the dominant and subdominant hemispheres were compared these values were found to be similar. In general, the results obtained could be evaluated as specific features of conditioned unilateral manipulatory reactions, characteristic for cortex and NS of brain hemispheres.
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PMID:[The neurochemical characteristics of the rat neostriatum and motor cortex after the acquisition of a unilateral manipulatory reflex]. 752 51

Indicators of the activity of acetylcholinesterase (ACE), 5'-nucleotidase (NT), adenylate cyclase (AC) in the sensorimotor cortex and the neostriatum (NS) of the right and left cerebral hemispheres of control rats and rats trained to perform a food-procuring movement by pressing against an obstacle with the forelimb. An identical level of the averaged bilateral values of the activity of NT and AC in both of the structures in question and an increased ACE activity in the NS were found in the control animals. After the development of a manipulatory skill, the activity of AC decreased in the cortex and the NS in the presence of unchanged ACE activity, while NT activity decreased in the cortex and increased in the NS. The bilateral values of the activity of the enzymes differed significantly in well and poorly trained rats. At the same time, the activity of the enzymes was similar in character in the dominant and subdominant hemispheres for each group of animals. Overall the neurochemical changes obtained can be regarded as specific correlates of the developed unilateral manipulatory reactions that are characteristic for the structures in question of both cerebral hemispheres.
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PMID:Neurochemical characteristics of the rat neostriatum and motor cortex after the development of a unilateral manipulatory reflex. 763 Apr 91

Is the chorion laeve merely a remnant of the chorion frondosum in placental development? Or is it metabolically active, having something to do with maternofetal interactions? In order to answer these questions at least in part, we determined the ultracytochemical localizations of some important enzymes such as nonspecific phosphatase (alkaline phosphatase), specific phosphatase (Ca(++)-ATPase and 5'-nucleotidase) and adenylate cyclase in the human chorion laeve at term. Strong activities of these enzymes were localized by ultracytochemistry on the plasma membrane of the trophoblast in the chorion laeve. These enzyme activities were confirmed by a series of cytochemical-control experiments, i.e., substrate-free control, heat-stability control, and inhibition control by inhibitors of alkaline phosphatase. These observations indicate that the chorionic trophoblast is probably metabolically active and that it might play an important role in the physiology of the fetal membrane.
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PMID:Enzyme-cytochemistry of human chorion laeve at term: enzyme localization on the chorionic trophoblast. 781 Nov 84

To better understand the mode of action of omega 3 fatty acids in cell membranes, human foreskin fibroblasts were grown in serum-free medium supplemented with 50 microM oleic acid linoleic acid, eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), and the effects on membrane composition, fluorescence polarization and enzyme activities were followed. The cells were enriched with EPA and DHA up to 7 and 13% of total lipids, respectively, of which > 95% was associated with phospholipids. In addition, the concentration of 22:5n-3 increased with both EPA and DHA to 7.5, and 2.1% of the total fatty acids, respectively. When compared to controls (oleic acid), cells treated with DHA showed a decrease in cholesterol, phospholipids, arachidonic acid (AA) and free cholesterol/phospholipid ratio (P < 0.05). In the presence of EPA, only decreases in AA and cholesterol were significant (P < 0.05). Membrane fluidity, assessed by fluorescence anisotropy, was increased 16% in cells enriched with DHA (P < 0.05), but showed no change with EPA or linoleic acid. There was an increase in membrane-associated 5'-nucleotidase (+27%) and adenylate cyclase (+19%) activities (P < 0.05), in DHA-enriched, but not in EPA-enriched cells, when compared with oleate controls. The studies show that incorporation of DHA, but not EPA, into cell membranes of fibroblasts alters membrane biophysical characteristics and function. We suggest that these two major n-3 fatty acids of fish oils have differential effects on cell membranes, and this may be related to the known differences in their physiological effects.
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PMID:Differential effects of eicosapentaenoic acid and docosahexaenoic acid on human skin fibroblasts. 785 7

The localization of some membrane-associated enzymes such as alkaline phosphatase, 5'-nucleotidase, glucose-6-phosphatase, Na+,K(+)-adenosine triphosphatase, adenylate cyclase and guanylate cyclase in the Merkel cell-axon complexes, trigeminal ganglia and the principal trigeminal sensory nucleus of the cat was determined at light and electron microscopic level using cytochemical techniques. In the sinus hair follicles (vibrissae), the reaction end product marking alkaline phosphatase and adenosine triphosphatase activities was visualized on the axons running through external follicle epithelium and the 5'-nucleotidase, adenylate- and guanylate cyclase positive reaction was seen to stain the plasma membranes of Merkel cells. In the trigeminal ganglia, the strongest alkaline phosphatase and adenosine triphosphatase activities showed the corresponding areas between the ganglion and satellite cells. 5'-nucleotidase activity was more intense on the neurilemmas and the surrounding glial plasma membranes. In the principle sensory trigeminal nucleus, the central neurons exhibited an intense alkaline phosphatase, 5'-nucleotidase and adenosine triphosphatase activities and much smaller amount of reaction product for adenylate cyclase and guanylate cyclase was observed. In conclusion, membrane-bound enzymes could be histo- and cytochemically demonstrated in all components of primary trigeminal afferent units. Our results have confirmed that the receptor function and the nerve impulses conductance need an intensive molecular and cation exchange, and energy supply.
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PMID:Primary trigeminal afferent neuron of the cat: I. Studies on membrane-bound enzyme histochemistry. 798 69

Is the chorion laeve merely a remnant of the chorion frondosum in placental development? Or is it metabolically active, having something to do with maternofetal interactions? In order to answer these questions at least in part, we determined the ultracytochemical localizations of some important enzymes such as nonspecific phosphatase (alkaline phosphatase), specific phosphatase (Ca(++)-ATPase and 5'-nucleotidase) and adenylate cyclase in the human chorion laeve at term. Strong activities of these enzymes were localized by ultracytochemistry on the plasma membrane of the trophoblast in the chorion laeve. These enzyme activities were confirmed by a series of cytochemical-control experiments, i.e., substrate-free control, heat-stability control, and inhibition control by inhibitors of alkaline phosphatase. These observations indicate that the chorionic trophoblast is probably metabolically active and that it might play an important role in the physiology of the fetal membrane.
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PMID:Enzyme-cytochemistry of human chorion laeve at term: enzyme localization on the chorionic trophoblast. 809 70


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