Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experiments were conducted on rats; in depression of blood cholinesterase activity by 68.6 percent phthalafos proved to decrease the myocardial nicotinamide coenzymes content on account of reduction in the amount of the oxidized forms. In the liver phthalafos diminished the content of oxidized and reduced forms of nicotinamide coenzymes, decreased the level of adenylic nucleotides chiefly at the expense of ATP. Diproxim prevented the changes caused by phthalafos in blood cholinesterase reactivation to 47.5 percent. It is supposed that the capacity of diproxim to normalize the oxidative processes in the cell by acting upon the nicotinamide coenzymes and adenylic nucleotides underlies its antidote action.
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PMID:[Effect of dipyroxime on the concentration of nicotinamide coenzymes and adenylate nucleotides in the myocardium and liver of rats poisoned with phthalophos]. 2 70

Transmural nerve stimulation (TNS) with 0.3-msec pulses between 1 and 25 Hz dilated cat cerebral artery segments in the presence of active muscle tone. Maximum vasodilatation occurred at 8 Hz. The dilator response to exogenous acetylcholine, but not to TNS, was abolished by atropine. Neither physostigmine nor hemicholinium affected the dilator response to TNS, which persisted after administration of guanethidine, phenoxybenzamine, propranolol, reserpine, and chronic sympathectomy. However, it was abolished by tetrodotoxin and cold storage. When examined histochemically, cat and rabbit cerebral arteries exhibited a rich plexiform distribution of acetylcholinesterase which was not affected appreciably by sympathetic denervation. These results suggest that vasodilation is not mediated through modification of sympathetic activity. They also indicate the existence of a nonadrenergic, possibly noncholinergic, vasodilator innervation in cat cerebral arteries. Preliminary studies suggest that the transmitter is not histamine, ATP, prostaglandins, gamma-aminobutyric acid, dopamine, or serotonin. The cat cerebral artery segments contrast with the isolated rabbit cerebral arteries which predominantly constrict in response to TNS and show a small dilator response.
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PMID:Neurogenic vasodilation of cat cerebral arteries. 2 5

The subsynaptic area of mouse diaphragm fibres was hyperpolarized by 1--2 mV during local curarization of the junctional zone in the presence of the reversible anticholinesteraze prostigmine (6 X 10(-6) M), or after treatment of the muscle with organophosphate cholinesterase inhibitor Soman. In a solution containing 5 mM K+ the mean hyperpolarization was 1.1 +/- 0.27 mV at mean resting potential--70 mV. After adding 2 X 10(-5) M ouabain the hyperpolarization increased to 1.5 +/- 0.25 mV. Removal of potassium ions from the bathing medium also increased curare induced hyperpolarization to 1.80 +/- 0.40 mV. Reactivation of membrane ATP-ase by addition of K+ after a period in K+-free medium reduced the hyperpolarization to zero, where measurements were performed 10--20 min after the readdition. It was concluded that spontaneous non-quantal leakage of acetylcholine occurs at the mouse neuromuscular junction, as it does in the frog (ref. Katz and Miledi 1977). Conditions which block the Na+-K+-dependent ATP-ase of nerve terminals increased the continuous leakage of ACh and activation of the pump decreased it.
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PMID:Electrophysiological examination of transmitter release in non-quantal form in the mouse diaphragm and the activity of membrane ATP-ase. 3 68

1. Female albino rats were treated with a total of 28 mg of chlormadinone acetate (CMA) for 28 days. In the adrenal cortex, the ovary, the vagina, and the uterus the activities of 3-beta-ol-steroiddehydrogenase, of dl-beta-OH-butric acid dehydrogenase, of alcaline and acid phosphatases, of DPN-diaphorase, of ATP-ase, and of non-specific esterases do not differ from untreated controls. 2. In the external muscle layer of the myometrium strong cholinesterase (ChE) activity was induced by C.M.A. A corresponding high ChE activity is normally found in immature rats or in estrus. 3. Furthermore, by treatment with CMA, ChE activity was induced in the tubular glands of the endometrium. This activity is found in the small parts of glomerate glandular terminals only but not in the rest of the glandular epithelium, nor in the epithelium of the cavum. It could be demonstrated that a corresponding ChE activity normally appears in the second third of pregnancy. The ChE activity induced by CMA was considerably higher and more widespread than during normal pregnancy. 4. It is concluded that in the endometrial glands a development similar to pregnancy is initiated by CMA. But development stops at the stage of ChE activity, thus leading to accumulation of ChE active cells.
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PMID:[Enzyme histochemical studies on the rat adrenal cortex, ovary, uterus and vagina following chlormadinone acetate administration, especially cholinesterase activity in myometrium and endometrium]. 5 Feb 31

In a patient with paroxysmal nocturnal haemoglobinuria (PNH) enzymatic activities of erythrocytes and leucocytes were studied. Studies of autohaemolysis were also performed. The following erythrocytary enzymes were measured: Glucose-6-phosphate dehydrogenase (G-6-PD), pyruvate kinase (PK), glutathione reductase (GR), and acetylcholinesterase (AcChE). The following enzymes were measured in leucocytes: Adenosine deaminase, purine nucleoside phosphorylase, adenine phosphoribosyltransferase, hypoxanthine phosphoribosyltransferase and adenosine kinase. Normal activity of G-6-PD, GR and PK in erythrocytes was found. In leucocytes and lymphocytes activity of purine nucleoside phosphorylase was reduced. Auto-haemolysis in vitro was increased, which could not be compensated by addition of glucose or ATP.
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PMID:Erythrocyte and leucocyte enzymes in a case of paroxysmal nocturnal haemoglobinuria. 10 10

A simple, reproducible method for the separation of human erythrocytes, described recently (Murphy, J. R. (1973) J. Lab. Clin. Med. 82, 334-341) has been utilized for the purpose of obtaining a wide range of biochemical data on these cells. Using phthalate ester density centrifugation of the fractions obtained by Murphy's method, we established that the cells were separated exclusively on the basis of their densities. Data on a wide range of biochemical and hematological parameters, when compared with previously reported density separation procedures showed that this simple technique can be used to fractionate the cells according to their densities (age) in their own plasma. Cells of increasing density consistently and reproducibly exhibited an increase in hemoglobin concentration, a moderate elevation in Na+ and a decrease in the following: K+, acetylcholinesterase, sialic acid, membrane protein, 2,3-diphosphoglycerate, ATP, cholesterol, phospholipid, mean corpuscular volume and critical hemolytic volume, However, no change in mean corpuscular hemoglobin was evident. The observed differences were not artifacts of the centrifugation process. This was determined in recentrifuged top fractions from which new top and bottom cells were obtained. The latter cells resembled the top fraction from which they were obtained, rather than the original bottom fraction. Whereas the parameters mentioned above exhibited consistency and reproducibility, such was not the case with the ATPase values. Depending on the cell density group examined and/or buffer as well as other conditions, significant variability in the activity levels of the ouabain sensitive, as well as the Ca2+ -stimulated ATPase, was observed. Use of these enzyme activities as indicators of cell age must be viewed with caution.
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PMID:Biochemical characterization of density-separated human erythrocytes. 12 56

Exposure of rat brain Na+ + K+-ATPase (ATP phosphohydrolase E.C. 3.6.1.3) to concentrations of cassaine greater than 1 x 10(-4) M resulted in a poorly reversible inhibition of this enzyme. Inhibition did not require the presence of ATP and developed rapidly, but the final amount of inhibition observed was independent of time. The amount of inhibition observed at a given concentration of cassaine was reduced by increasing the concentration of membranes in the system. The inhibition of Na+ + K+-ATPase activity was associated with equivalent inhibition of the phosphorylation and (3H)-ouabain binding reactions of this enzyme, while the uninhibited enzyme was apparently kinetically normal. Concentrations of cassaine which produced this stable inhibition of Na+ + K+-ATPase had no effect on the Mg2+-activated ATPase or the NADH cytochrome-c-reductase activities of crude rat brain microsomal preparations. Cassaine inhibited the cholinesterase activity of rat brain microsomes with a Ki of about 5 x 10(-5) M, but his inhibition was fully reversible. The poorly reversible inhibitory actions of cassaine, thus, appeared specific for Na+ + K+-ATPase. Because this stable pattern of inhibition of the Na+ + K+-ATPase by cassaine required drug concentrations at least one hundred-fold greater than those which produce positive inotropic effects, it appears unlikely that this pattern of Na+ + K+-ATPase inhibition is involved in the cardiotonic actions of this drug.
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PMID:Studies on the stable inhibition of Na+ + K+-ATPase by cassaine. 13 Feb 44

The activity of ATP-ase and acetylcholinesterase (AChE) in crude mitochondrial fraction (CMF) and microsomal fraction of rat brain cortex and the spinal cord was studied in clonic seizures evoked by electroshock and 5 min after them. Inhibition of the Na, K-ATP-ase activity of the CMF of the brain at the clonic phase of convulsions and an increase in the activity of this enzyme in all the fractions of the tissues under study at the postconvulsive period were revealed. The activity of Ca-ATP-ase in the CMF of the brain increased during the convulsions and decreased at the postconfulsive period. The activity of Mg-ATP-ase remained unchanged. The AChE activity, as a rule increased during the convulsions, and grew even more during the postconvulsive period; the spinal cord tissue displayed a reduction of the activation effect. A possibility of structural reconstructions in the excitable neuron membranes during the convulsive activity is discussed.
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PMID:[Na, K-ATP-ase and acetylcholinesterase activity of the membrane structures of the rat brain and spinal cord during the seizure process]. 13 79

The action of morphine (20 mg/kg) and phenobarbital (80 mg/kg) on the activity of acetylcholinesterase (ACS) and Mg2+-dependent ATP-ase in fractions of unpurified mitochondria and neuronal mitochondria of the rats brain was studied. It is shown that with prolonged introduction of both morphine and phenobarbital the dynamics of the Mg2+-dependent ATP-ase activity in fractions of neuronal mitochondria and synaptosomes is dissimilar, the synaptosomes fractions then displaying a specific influence of morphine and phenobarbital on the Mg2+-dependent ATP-ase activity, while in the neutronal mitochondria fraction changes occurring in the activity of this enzyme proved to be analogus to those taking place after administration of both morphine and phenobarbital. The ACS activity in the synaptosomes fraction following introduction of both morphine and phenobarbital did not differ from the control one.
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PMID:[Effect of narcotics on the enzymatic activity of neuronal and synaptic mitochondria of rat brain]. 14 Aug 13

Nerve cell bodies, large and multipolar, were isolated in bulk with the least possible contamination from the pig brain stem. The activities of two neurobiologically important membrane enzymes, Na+, K+-ATPase, and acetylcholinesterase, in the isolated cell bodies were estimated. Na+, K+-ATPase [EC 3.6.1.4], more accurately called ouabain-sensitive ATPase of the nerve cell body, hydrolyzed 94 micronmoles of ATP per h per 100 mg of protein. This activity was one-fourth that in the brain stem. Nerve cell bodies contained a large amount of Ca2+, 275 micronmoles per 100 mg of protein, about half of which was calculated to exist as compounds other than calcium orthophosphate. However, the Na+, K+-ATPase of the nerve cell bodies was not stimulated by EGTA, in contrast to that of the brain stem. Acetylcholinesterase [EC 3.1.1.7] and cholinesterase [EC 3.1.1.8] activities were estimated separately by the use of the specific inhibitors Persidol and BW 284C51 dibromide. Acetylcholinesterase was almost completely responsible for the hydrolysis of acetylcholine in the nerve cell bodies isolated from the brain stem and little cholinesterase activity was detected. 1300-1400 micronmoles of acetylcholine was hydrolyzed per h per 100 mg of protein of the neuronal cell bodies; this activity was about four times higher than that in the brain stem. The differences between the specific activities of Na+, K+-ATPase, and acetylcholinesterase in theneuronal cell bodies and the brain stem are discussed in the light of electron microscopic analysis of the distribution of these enzymes and the preservation of the plasma membrane of the isolated cell bodies.
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PMID:Biochemical characterization of the neuron. ATPase and acetylcholinesterase activities of neuronal cell bodies isolated in bulk from the pig brain stem. 14 Aug 66


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