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)

Three and 4 day old embryonic chicken hearts were examined for their responsiveness to acetylcholine and presence of acetylcholinesterase (AChE) to determine the role of the enzyme in the cardiac effects of the transmitter. The effects of acetylcholine on rate and contractility of 3 day old hearts were indistinguishable from those on 4 day old hearts. The effects were readily blocked by atropine at both stages of development. In 3 day old hearts the responses to acetylcholine were not affected by the AChE inhibitor physostigmine but in 4 day old hearts they were considerably potentiated. The effect of acetylcholine on the rates of 4 day old hearts is of short duration (5 min or less). In 3 day old hearts it persists for a much longer time. Thus, the appearance of AChE in the embryonic heart of the chicken does not seem to modify the responsiveness of the cholinergic receptor to the transmitter.
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PMID:Acetylcholinesterase and responses to acetylcholine in the embryonic chicken heart. 0 92

The effect of hemicholinium-3 (HC-3) on responses of the rat isolated bladder and ileum to acetylcholine and carbachol was investigated in the absence and presence of a number of anticholinesterases. Responses of the bladder to acetylcholine were potentiated by DFP, edrophonium, BW284C51 and physostigmine but were unaffected by the specific butyrylcholinesterase inhibitor iso-OMPA. Responses to carbachol were not potentiated by the anticholinesterases. HC-3 (1.7 X 10(-4) M) inhibited responses to carbachol without affecting those to acetylcholine. In the presence of physostigmine or DFP responses to acetylcholine were inhibited by HC-3 but no such inhibition was observed in the presence of BW284C51, edrophonium or iso-OMPA or a combination of the latter two anticholinesterases. Responses to carbachol were also inhibited to a greater extent in the presence of DFP. In the ileum, responses to acetylcholine were increased in the presence of DFP, edrophonium and physostigmine but were unaffected by iso-Ompa. responses to carbachol were not increased by any of the anticholinesterases. HC-3 (2.8 X 10(-4) M) inhibited responses to both acetylcholine and carbachol in the ileum and the degree of inhibition was not significantly altered by the presence of any of the anticholinesterases used. Although a weak anticholinesterase, HC-3 was also found to decrease the inhibitory action of physostigmine on the hydrolysis of acetylcholine by homogenates of rat ileum. A similar effect was noted with DFP but not with edrophonium. The results obtained do not support a prejunctional action for HC-3 in antagonizing responses to carbachol. It is concluded that in addition to an inhibitory action on the post-junctional muscarinic receptor HC-3 may interfere with the anticholinesterase activity of some cholinesterase inhibitors such as physostigmine and DFP but not edrophonium.
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PMID:The effect of cholinesterase inhibitors on the antimuscarinic effect of hemicholinium-3 (HC-3) in the rat. 0 55

Acetylsecohemicholinium No. 3 (AcHC-3), the acetate of the open ring (seco form of hemicholinium No. 3, HC-3) hydrolyzes in vitro to the hemiacetal HC-3 at pH values above 9, a temperature-dependent conversion illustrated by ultraviolet spectral shifts from 305 to 257 mmu, and to a limited extent by certain esterases as measured by manometric analysis. An LD50 of 125 mug/kg for a neutral solution of AcHC-3 was decreased to 78.3 mug/kg (the LD50 of HC-3) upon being made basic. Prolonged treatment of mice with LD10-20 doses of AcHC-3 was associated with decreased fatty acid oxidation in the liver and resulted in infiltration of fat into hepatic cells, a reaction preventable by treatment with small doses of choline (10 mg/kg). AcHC-3 causes neuromuscular and autonomic ganglionic blockade, cholinesterase inhibition, and in vitro inhibition of acetylcholine (ACh) synthesis. These actions, although HC-3-like, appear to be due to AcHC-3 rather than HC-3 since neither cholinesterase inhibition nor hepatic ligation altered the neuromuscular blocking actions of AcHC-3. In addition to its HC-3-like properties, AcHC-3 consistently produced a transient increase in twitch height of gastrocnemius muscle before blockade and was dose-responsive in depressing blood pressure and in eliciting contractions of the isolated guinea pig ileum. AcHC-3 is both a cholinomimetic (depresses arterial blood pressure, decreases heart rate and increases ileal contractions) and a competitor of acetylcholine. That is, in most preparations tested, AcHC-3 at lower concentrations has as much intrinsic activity as ACh and at somewhat higher concentrations competitively blocks the responses to ACh. These cholinomimetic actions may be due to the presence of two ACh moieties on the AcHC-3 molecule which attach to cholinergic receptor sites. Also noted was an action of AcHC-3 that seems to be peculiar to the secohemicholiniums, namely, the potentiation of catechloamines.
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PMID:Acetylsecohemicholinium: chemical and pharmacological evaluation of an open-ring hemicholinium. 0 97

The histrochemistry of the adrenal glands was studied in four adult male marmosets (two Callithrix jacchus and two Callithrix penicillata). It was impossible to demonstrate any reactivity to UDPG-GT, ADH, alanyl aminopeptidase, leucine aminopeptidase, xilitol (NAD-dependent) dehydrogenase, beta-glucuronidase and aryl-sulfatase in these glands. Total phosphorylase was found in scattered cells of the glomerulosa and adjacent outer fasciculata of one C. penicillata. The dehydrogenases (LDH, G-6-PDH,6-PGDH, NADPH2-TR,ICDH,SDH,NADH2-TR, alpha-GPDH, beta-OHBDH) as well as the hydrolases (except alkaline phosphatase, ATPase, and acetylcholinesterase) showed a stonger reactivity in the cortical part. Some hydrolases (naphthol acetate esterase, acid phosphatase) and cytochrome oxidase were less reactive in the zona glomerulosa, where the dehydrogenases were more abundant. The outer fasciculata and the reticularis also showed a strong dehydrogenase reactivity.
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PMID:Histochemical studies on the adrenal glands of the marmosets (Callithrix jacchus and Callithrix penicillata). 0 44

Patients with atopic dermatitis have abnormal autonomic responses of the arterioles, pilomotor smooth muscle, and sweat glands. Their lesions have been reported to contain increased amounts of the neurohumors, acetylcholine and norepinephrine, as well as increased activity of acetylcholinesterase and catechol-O-methyltransferase. In vitro studies of epidermis show that beta adrenergic agonists fail to evoke the normal inhibition of mitosis of basal cells of patients with atopic dermatitis. Epidermis removed not only from the lesions, but also from normal-appearing skin, responded abnormally. The increase in intracellular levels of cAMP after exposure to catecholamines was similar in normal and atopic epidermis. Lymphocytes and PMN leukocytes isolated from patients with atopic dermatitis show both a decreased physiologic response (glycogenolysis and inhibition of lysosome enzyme release) and a decreased rise in intracellular levels of cAMP upon incubation with beta agonists, but a normal response to PGE1. Cortisol increases the response of lymphocyte adenyl cyclase to both agonists and, in the case of the patients with atopic disease, more than overcomes the depressed response to beta agonists. Because the leukocytes respond normally to PGE1 and because others have reported normal activities of skin and adenyl cyclase, phosphodiesterase, and protein kinases, we conclude that the step responsible for the diminished beta adrenergic response lies antecedent to the catalytic site of adenyl cyclase.
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PMID:Adrenergic mechanisms and the adenyl cyclase system in atopic dermatitis. 0 56

Cholinesterase activities in the hearts and ganglia of an oyster (Crassostrea virginica) and a venerid clam (Macrocallista nimbosa) were measured and compared. Tissue extracts were partially purified by ammonium sulfate fractionation followed by gel column chromatography. Enzymatic activity was assayed spectrophotometrically; substrates were acetyl-, butyryl-, and propionylthiocholine (ATC, BTC, PTC). Kinetic constants characterizing each enzyme were derived. At all substrate concentrations, the hydrolysis rates of both clam enzymes were in the order: BTC greater than PTC greater than ATC. With oyster enzymes the ranking was ATC greater than or equal to PTC greater BTC. The specific activities of oyster heart and ganglion enzymes were similar. In contrast, clam ganglion extracts were 75-100 times more active than clam heart extracts and, with any substrate, had greater activity than either oyster enzyme. All enzyme preparations proved to be homogeneous on the bases of constant substrate activity ratios in successive column fractions, and of intermediate velocities with mixed substrates. Six cholinesterase inhibitors were tested. The specific acetylcholinesterase antagonist, B.W. 62C47, WAS MUCH MORE EFFECTIVE AGAINST OYSTER ENZYMES, WHILE THE SPECIFIC ANTIBUTYRYLCHOLINESTERASE, ISO-OMPA, almost totally inhibited calm enzyme activity, but had little effect on oyster. Eserine was the most effective inhibitor of both enzymes. In conclusion, the enzymes in oyster tissues are acetylcholinesterases, while clam enzymes are butyrylcholinesterases. Nevertheless, clam ganglion esterase is sifficiently active to hydrolyze the physiological substrate, acetylcholine. These results explain the long-observed differences in isolated heart pharmacology between ostreid and venerid bivalves.
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PMID:A comparison of the cholinesterases of an oyster (Crassostrea virginica) and a clam (Macrocallista nimbosa). 1 Mar 39

Activation of cholinergic neurons in the brain is produced by administration of the acetylcholinesterase inhibitors physostigmine and diisopropylfluorophosphate (DFP). This activation has a biphasic effect on tyrosine hydroxylase (EC 4.14.3-) activity. The acute effect of DFP, 1 mg/kg, intraperitoneally, or physostigmine, 0.2 mg/kg, intravenously, or 10 mug, intraventricularly, was a rapid reduction in tyrosine hydroxylase activity in the hypothalamus. The activities of DOPA decarboxylase (EC 4.1.1.28) and dopamine-beta-hydroxylase (EC 1.14.17.1) were not changed. In contrast to the acute effect, chronic administration of physostigmine, 0.2 mg/kg, intravenously, twice daily for 7 days produced an increase in tyrosine hydroxylase activity in the hypothalamus. The rapid acute effects may be due to an allosteric inactivation of tyrosine hydroxylase, while the chronic effects may reflect enzyme induction.
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PMID:Reduction in brain tyrosine hydroxylase activity following acetylcholinesterase blockade in rats. 1 Oct 41

A commercial controlled-pore glass medium for exclusion chromatography which is substituted with glycerol to eliminate non-specific adsorption (Glyceryl-CPG) was examined. Experiments on the elution of acetylcholinesterase and ganglioside micelles at varied ionic strength and pH showed that a slight anionic character still persisted on the glass matrix. At ionic strengths above 0.1, this had no effect on the elution of proteins. The material was found to have no tendency to adsorb proteins and other compounds, and was judged an excellent medium for exclusion chromatography. As a support for affinity chromatography, Glyceryl-CPG could be activated by periodate to form a virtually neutral matrix-ligand system.
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PMID:Residual anionic properties of a covalently substituted controlled-pore glass, glyceryl-CPG. 1 90

Cell division, neurite formation and acetylcholinesterase activity were examined in a clone (NBA2) of mouse neuroblastoma cells maintained for up to 120 hours in medium with pH values between 6.6 and 8.0. Growth rate decreased as pH was reduced from 7.8 to 6.6. Generation time at pH 7.4 was 25 hours, while the rate of cell division was negligible at pH 6.6. The total number of cells at stationary phase was less at the lower pH values. Neurite formation was enhanced markedly as the pH was reduced from 7.4 to 6.6. Acetylcholinesterase activity was 5- to 8-fold greater in cells exposed to medium at pH 6.6 than in cells maintained in medium at pH 7.4. The reduction in the rate of cell division and increases in neurite formation and acetylcholinesterase activity at pH 6.6 were reversible upon exposure of the cells to pH 7.4 medium. Cell viability was greater than 90% at all medium pH values over a period of 120 hours. Uncloned T-59 mouse neuroblastoma cells were affected similarly by changes in pH. These results show that manipulation of the environmental pH can reversibly alter growth, neurite formation, and acetylcholinesterase activity of mouse neuroblastoma cells in culture.
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PMID:The effect of medium pH on rate of growth, neurite formation and acetylcholinesterase activity in mouse neuroblastoma cells in culture. 1 20

A method is described for the assay of acetylcholinesterase in tissue samples using the selective cholinesterase inhibitor, lysivane (10-(alpha-diethylaminopropyl) phenothiazine hydrochloride). Significantly increased enzyme activity is found in rectal biopsy specimens from patients with Hirschsprung's disease (p less than 0.001) indicating the diagnostic usefulness of the assay.
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PMID:An improved method for the determination of acetylcholinesterase activity in rectal biopsy tissue from patients with Hirschsprung's disease. 1 96


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