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)

Acetylcholinesterase activity is shown in the renal nerves of the rat with the technique of Karnovsky and Roots. By light microscopy, the acetylcholinesterase-positive nerves are seen in association with blood vessels, including the glomerular arterioles, and occasionally with renal tubules. By electron microscopy the precipitate appears extracellularly around axons and varicosities. DFP inhibits the deposition of precipitate. Previous demonstration by serial section electron microscopy in the rat revealed that all nerves around the glomerular arterioles contain small dense-cored vesicles characteristic of adrenergic nerves, indicating that the acetylcholinesterase-positive nerves demonstrated here are likely to be adrenergic nerves containing acetylcholinesterase.
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PMID:Light and electron microscopic localization of acetylcholinesterase activity in the rat renal nerves. 97 Mar 52

Out of 12 oximes and amidoximes (3 of which were new to the literature) the following showed a distinct antilethal effect in DFP poisoning: RA14 (1-methylbenzimidazole-2-aldoxime methiodide), RA14 (pyridine-4-aldoxime dodecyl bromide), and RA24 (pyridine-2-aldoxime dodecyl bromide). These compounds also reactivated acetylcholinesterase (AChE) in vitro, but had no effect on this enzyme in vivo. Moreover, addition of the dodecyl chain to pyridinealdoxtimes, or in a less degree replacement of the pyridine ring with benzimidazole in aldoximes, distinctly increased acute toxicity and lipophilicity when compared with the parent pyridine compounds, along with protective action in DFP poisoning.
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PMID:Potential acetylcholinesterase reactivators: oxime and amidoxime derivatives. 101 93

Aminoalkyl benzenesulfonyl fluorides, like organophosphates, act as irreversible inhibitors of serine proteinases by splitting off hydrogen fluoride to form an enzyme-inhibitor complex, stable in the physiological pH region. Several of these compounds are characterized by a higher rate of inhibition when trypsin is used and the second order rate constants are compared with those of organophosphates. On the other hand, upon inhibition of human serum cholinesterase by DFP and 4-nitrophenyl diethyl phosphate, some orders of magnitude higher than that of benzenesul fonyl fluorydes are observed. As shown by an oral toxicity study in mice similar differences exist with respect to LD50 values.
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PMID:[Inhibition of the activity of human serum cholinesterase by aminoalkyl benzenesulfonyl fluorides]. 102 6

Adrenalectomy decreased the rate of regeneration of brain and striated muscle acetylcholinesterase (EC 3.1.1.7) in mice after sublethal poisoning with diisopropylphosphofluoridate (DFP). This may explain similar findings in previous experiments in hypophysectomized animals.
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PMID:Effect of adrenalectomy on the synthesis of cholinesterases. 106 80

1. Longitudinal muscle strips of the guinea-pig ileum were incubated in Tyrode solution containing either DFP or physostigmine as cholinesterase inhibitor. After a 90 min preincubation period the acetylcholine resting release into the medium was determined. Acetylcholine was estimated by gas chromatography. 2. The resting release was 0.39 nmol/g times min irrespective of the cholinesterase inhibitor used. In the presence of hexamethonium, or after omission of external calcium, the resting release fell by 50 and 55 per cent, respectively. 3. Oxotremorine (10-5 and 10-4M) significantly inhibited the resting release of acetylcholine by 25 and 33 per cent, respectively. The inhibitory effect of oxotremorine was completely reversed by atropine (3 times 10-7 M). Oxotremorine did not reduce the spontaneous release of acetylcholine that occurred either in the presence of hexamethonium or in the absence of external calcium. 4. The acetylcholine content of the muscle strips was approximately doubled during the preincubation with a cholinesterase inhibitor. The subsequent incubation with oxotremorine did not lead to a further increase in the endogenous acetylcholine content. However, incubation of the muscle strips with oxotremorine in the absence of a cholinesterase inhibitor led to a rise in the endogenous acetycholine concentration. In in vivo experiments, oxotremorine also caused an increase in the acetylcholine content of the muscle strips. The possibility is discussed that the rise in the acetylcholine concentration following the administration of oxotremorine is a consequence of the decreased release. 5. It is concluded that oxotremorine inhibits the resting release of acetylcholine by activation of neuronal muscarinic receptors. The inhibitory effect of exotremorine is linked to that fraction of the acetylcholine resting release that is calcium-dependent and that arises from propagated activity in cholinergic neurones. The results are consistent with the hypothesis of a feed-back control of acetylcholine release mediated by inhibitory muscarinic receptors.
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PMID:Inhibition by oxotremorine of acetylcholine resting release from guinea pig-ileum longitudinal muscle strips. 111 41

N-Heterocyclic acraldoximes methiodides, where the heterocyclic residues are 2-, 3-, and 4-pyridyl, 2-(1-methyl)imidazolyl or 4-pyrimidyl, were prepared and tested for their reactivating potency on acetylcholinesterase inhibited from diisopropylphosphorofluoridate (DFP). The in vitro testing revealed that the new compounds are good reactivators of the phosphorylated electric eel cholinesterase. The structure-activity relationships are briefly discussed.
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PMID:Structure-activity relationships in reactivators of organophosphorus-inhibited acetylcholinesterase. 9. N-Heterocyclic acraldoximes methiodides. 115 2

A pharmaco-histochemical regimen was used to examine the morphology and internal organization of acetylcholinesterase (AChE, EC 3.1.1.7) neurons in brain areas--the caudate-putamen nucleus, nucleus accumbens, olfactory tubercule, and subtantia nigra--monoaminergically characterized in terms of their dopamine content. Intense, homogenous staining is produced in these neural regions by other histochemical protocols for AChE; individual AChE-containing neurons cannot be observed reliably or consistently. With the present technique, based on the differential regeneration of AChE in the separate subcellular compartments of the neuron (i.e., axon, dendrite, soma) after intramuscular injection of bis-(1-methylethyl)-phosphorofluoridate (di-isopropylfluorophosphate: DFP), it was shown that AChE was associated with neurons whose cell bodies lay within the brain areas studied. Although the significance of dopaminergic-cholinergic relationships in the caudate-putamen complex, nucleus accumbens, and olfactory tubercule could not be established on the basis of these new histochemical data, arguments were presented indicating that dopamine neurons in the zona compacta of the substantia nigra also contained AChE.
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PMID:Acetylcholinesterase neurons in dopamine-containing regions of the brain. 118 60

1. Tissues examined for the histochemical localization of choline acetyltransferase are best fixed by acetone. 2. Topographical identification of choline acetyltransferase by its reaction products is not only substrate-dependent because a slight staining also occurred in the absence of the substrates choline and acetyl-coenzyme in the incubation medium. 3. Histochemical localization of choline acetyltransferase was inhibited by sarin but not by DFP or eserine. 4. According to Burt and Silver's method cells and cell organelles, of which the enzymatic content is doubtful, where stained. 5. Chloroacetylcholine-perchlorate did not inhibit the histochemical localization of choline acetyltransferase. 6. The staining of acetylcholinesterase showed a different topographical distribution although both methods were inhibited by sarin.
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PMID:Studies about the specificity of the histochemical localization of choline acetyltransferase. 121 44

Infusion of 1 mul arachis oil containing 1.5 mug bis-(1 -methylethyl)phosphorofluoridate (di-isopropylfluorophosphate: DFP) into the caudate--putamen nucleus and substantia nigra of rats produced a considerable reduction of histochemical staining for acetylcholinesterase (AChE) in these two brain regions 30--120 min after injection. Thereafter, regeneration of AChE occurred within the zone of DFP effect. These new stores of AChE were associated with discrete neuronal perikarya and their processes. Intracerebral DFP administration had little or no histochemically detectable effect on NADH-diaphorase. Thionin staining was similarly unaffected. The results with punctate intracerebral application of DFP were replicated by intramuscular injection of 1.5 mg/kg DFP. Although the significance of dopaminergic--cholinergic interactions in the neostriatum could not be elucidated on the basis of these histochemical data, the thesis was advanced that dopamine neurons in the pars compacta of the substantia nigra also contained AChE, possibly to inactivate acetylcholine released from cholinergic fibers afferent to this neural structure.
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PMID:Acetylcholinesterase-containing neurons in the neostriatum and substantia nigra revealed after punctate intracerebral injection of di-isopropylfluorophosphate. 123 57

The postnatal development of acetylcholinesterase (AChE, EC 3.1.1.7) and NADH-diaphorase was examined in the caudate-putamen nucleus and substantia nigra of rats ranging from 3 to 90 days in age. From 3 to 15 days post partum islands of AChE and NADH-diaphorase activity were observed in the caudate-putamen nucleus. Individual neuronal somata could also be seen in AChE-stained sections up to 15 days. At later ages neuropil staining became increasingly dense, and this presumably accounted for the infrequent visualization of cell bodies in the brains of older animals. During development AChE appeared in the caudate-putamen nucleus in a lateral to medial topographic order; analogously, enzyme staining in the neostriatum reappeared in the same lateral to medial topographic order in adult rats following irreversible AChE inhibition by intramuscularly injected bis-(1-methylethyl)phosphorofluoridate (di-isopropylfluorophosphate: DFP). Furthermore, DFP treatment in mature animals revealed the presence of AChE in striatal neurons having morphologies similar to those observed in newborn rats. A similar time-course of postnatal AChE development was observed in the substantia nigra. In both the pars compacta and pars reticulata individual cell bodies, which were visible at early ages (3-10 days), became increasingly obscured at later times after birth by extra-somata staining. Between the 6th and 15th postnatal days AChE-containing fibers were seen projecting apparently from pars compacta into pars reticulata. Comparison of the present results with histochemical data of other investigators on the postnatal development of monoamines indicated the likelihood of cholinergicmonoaminergic interactions in the neostriatum and substantia nigra.
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PMID:Postnatal development of acetylcholinesterase in the caudate-putamen nucleus and substantia nigra of rats. 127 70


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