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)

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

After discussion of the modern concepts of pathophysiology of ocular myasthenia the ocular symptoms such as ptosis and eye muscle palsies are discussed. As important diagnostic sign the Simpson lid fatigue test before and after application of Tensilon is described. For diagnosis of myasthenic eye muscle palsies electrooculography has a special significance especially in connection with the application of Edrophonium, which normalizes myasthenic hypometric saccades and transforms them even in hypermetric saccades. In doubtful cases of eye muscle palsies the electromyogram of the affected muscle in connection with the Edrophonium-test is extremely valuable. With regard to modern treatment apart from cholinesterase inhibitors (Pyridostigmine, Neostigmine) thymectomy, the application of corticosteroids, ACTH and especially also immune suppressive drugs (Imurel etc.) is discussed. Of great significance in ocular myasthenia is the local application of cholinesterase inhibitors like Eserine, Prostigmin or Phospholine Iodide.
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PMID:[Diagnosis and treatment of ocular myasthenia (author's transl)]. 20 42

The origin of the cholinergic innervation to the amygdaloid complex was investigated with the use of acetylcholinesterase (AChE) histochemistry and choline acetyltransferase (ChAT) assay of microdissected nuclei. Visualization of AChE-positive neurones in the ventral forebrain was facilitated by pretreatment of rats with 1.5 mg/kg di-isopropyl phosphofluoridate (DFP). The AChE-positive neurones in the ventral forebrain are distributed in a continuous system from the septum through the lateral preoptic area to the entopeduncular nucleus caudally. Knife cuts or kainic acid injections (1.5 microgram/l microliter) placed in the lateral preoptic area resulted in substantial depletion of the AChE and ChAT content of the amygdala nuclei. Kainic acid injections (1.5 microgram/l microliter) in the diagonal band area or cuts through the stria terminalis dorsally did not significantly modify the AChE staining or ChAT content of the amygdala (although diagonal band injections partially depleted the hippocampus of ChAT). Knife cuts severing both the so-called ventral pathway and the stria terminalis did not produce significantly greater ChAT depletion in the amygdala than those produced by the knife cuts or kainic acid injections in the lateral preoptic area. Parasagittal knife cuts undercutting the lateral pyriform cortex also failed to modify the AChE or ChAT content of the amygdala, but they depleted the undercut cortex of both ChAT and AChE; AChE-positive material accumulated ventrally and medially to the knife cut. It is suggested that the major source of the cholinergic innervation of the amygdala is the magnocellular AChE-positive neurones in the lateral preoptic area and adjacent regions of the ventral forebrain.
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PMID:Choline acetyltransferase and acetylcholinesterase containing projections from the basal forebrain to the amygdaloid complex of the rat. 31 Dec 37

The distribution of acetylcholinesterase (AChE, EC3.1.1.7) within extrapyramidal and related structures was studied in 4 monkeys following the i.m. administration of bis-(1-methylethyl) phosphorofluoridate (di-isopropylfluorophosphate: DFP). In 1 animal, sacrificed 4 hr after the injection of 0.43 mg/kg C, AChE is virtually absent in all structures. In the other 3 animals, which received 0.20 mg/kg DFP 10, 12 and 18 hr prior to sacrifice, AChE activity is greatly reduced in the neuropil of those structures which normally show intense AChE activity in pharmacologically unmanipulated monkeys. As a consequence of the lower background AChE activity in the latter 3 DFP-treated monkeys, the perikarya and processes of several groups of neurons can be readily identified. The perikarya and processes of two types of neurons of the neostriatum, representing a small percentage of all neurons in this structure, are intensely stained. They apparently correspond to the chromatic giant aspiny neurons and the achromatic medium-size "spidery aspiny" neurons. Most perikarya and processes of the neurons of the medial and lateral divisions of the pallidum, as well as the morphologically similar neurons of the pars reticulata of the substantia nigra, display light to moderate AChE activity. The pars compacta of the substantia nigra contains a small number of intensely stained elongated and triangular neurons and numerous moderately stained ovoid neurons whose processes are very lightly reactive. The cell bodies of the neurons of the subthalamic nucleus and associated groups of neurons (nucleus ansae peduncularis) are moderately stained whereas the perikarya and processes of the subnucleus compactus of the pedunculopontine tegmental nucleus are intensely and moderately stained, respectively. Numerous large and multipolar neurons associated with the lenticular nucleus (intralamellar groups) or the pallidum (peripallidal groups) including the nucleus ansae lenticularis have somata and processes which show an intense AChE activity. Certain of the latter groups of neurons, partially interspersed with the neurons of the substantia innominata, correspond in part to the nucleus basalis of Meynert. The present data are compatible with the idea that the large AChE neurons of the neostriatum may be the source of the acetylcholinesterasic striatopallidal and strionigral fibers. The similarity between the neurons of the pallidum and those of the pars reticulata of the substantia nigra suggests that the latter structure may represent a caudal extension of pallidal tissue. Therefore, the nigrothalamic projection, which has been claimed to originate in the pars reticulata of the substantia nigra, would correspond to pallidothalamic projections.
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PMID:Morphological characteristics of the acetylcholinesterase-containing neurons in the CNS of DFP-treated monkeys. 40 43

The present study examined the possibility that subsensitivity to pilocarpine might occur following a single injection of the irreversible anticholinesterase agent, DFP. In one experiment male Sprague-Dawley rats were trained to drink from experimental drinking chambers for 1/2 h per day. After establishment of baselines, pilocarpine hydrochloride (8 mg/kg) was injected i.p. 5 min before the drinking session. One week later DFP or the arachis oil vehicle (1 mg/kg) was injected intramuscularly and injections of pilocarpine were given at varying times thereafter. The suppression of water intake by this dose of pilocarpine was unaffected by pretreatment with arachis oil, but was markedly attenuated by pretreatment with DFP. This subsensitivity was first observed on the second day but had largely disappeared by the 14th day. DFP was found to have comparable effects on water intake and brain acetylcholinesterase activity when the injections were separated by 20 days. In a second experiment the hypothermic effects of pilocarpine were found to be reduced in rats acutely treated with DFP. These data establish that subsensitivity to pilocarpine occurs following a single administration of DFP. This subsensitivity could reflect a reduced sensitivity of postsynaptic receptors to acetylcholine, which may partially account for the behavioural recovery of the rats while acetylcholinesterase activity is still markedly depressed.
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PMID:Development and disappearance of subsensitivity to pilocarpine following a single administration of the irreversible anticholinesterase angent, DFP. 40 29

The multiple forms of acetylcholinesterase (AChE, E.C. 3.1.1.7) have been investigated with regard to their histochemical demonstrability. Their pattern is influenced by buffer treatment, fixation, and by incubation conditions causing aggregation and disaggregation as well as loss or inactivation of individual forms. The standard histochemical method for AChE preferentially demonstrates the high molecular forms. Most of the oligomer forms are washed out or inactivated. A selective demonstration of the highly aggregated forms is possible either by inhibition of the oligomers with diisopropylfluoridate (DFP) or by specifically dissolving them out. No reason could be found for the selective demonstration of the low molecular weight forms.
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PMID:The multiple forms of brain acetycholinesterase. III. Implications for the histochemical demonstration of acetylcholinesterase. 51 95

Brief treatment with 10(-4)M diisopropylfluorophosphate (DEP) irreversibly inactivates acetylcholinesterase (E.C.3.1.1.7; acetylcholine hydrolase) (AChE) activity in 10 day old chick embryonic muscle cultures. Electron microscopic cytochemistry was employed to follow the distribution of new AChE during recovery from DEP treatment. In normal 10 day cultures of embryo pectoralis muscles AChE is localized in the nuclear envelope, perinuclear sarcoplasm, sarcotubular system, subsurface vesicles and bound outside the cells. Immediately after DFP treatment AChE activity is absent in large myotubes. Within 15 min, activity is randomly present in small amounts in the sarcotubular system and nuclear envelope. There is a dramatic increase in activitv in the nuclear envelope during the 1st hr of recovery, and connections between the nuclear envelope and sarcotubular system are often seen. The next few hr of recovery show increased AChE activity. By 4 hr activity approaches that of controls. Six to 8 hr after treatment, AChE activity can be detected spectrophotometrically in the medium and can be seen bound outside the cells with the electron microscope. The spatial and temporal patterns of AChE activity demonstrate that the recovery of AChE and its mobilization and release from DFP-treated cells are not governed solely by the levels attained by the enzyme in the cultured embryo muscle.
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PMID:Ultrastructural localization of acetylcholinesterase in cultured cells. III. DFP treated embryo muscle. 56 40

Central actions of pro-2-PAM (dihydroderivative of 2-PAM) and 2-PAM in poisonings with DFP have been studied. It was shown that pro-2-PAM significantly increased activity of DFP inhibited acetylcholinesterase in the brain, quickly ceased the DFP-induced paralysis of respiration, partially normalized the DFP-induced abnormalities in electrocorticogram and increased the convulsive dosis of DFP. Effects of 2-PAM in these experiments were negligible.
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PMID:Central therapeutic effects of dihydroderivative of pralidoxime (pro-2-PAM) in organophosphate intoxication. 67 65

2-Hydroxyiminomethyl-4-alkylpyridine methiodides were prepared and tested for their in vitro reactivating potency on phosphorylated electric eel cholinesterase. They were also tested as in vivo protecting agents: only one of the compounds, 4-methyl-2-hydroxyiminopyridine, offered a greater protection from DFP than 2-PAM, the others had little to no effect.
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PMID:[Structure-activity relationship in reactivators of acetylcholinesterase inhibited by phosphoric esters. XII. Hydroxyiminomethylalkylpyridine iodomethylate]. 73 50

The ontogeny of esterase isozymes in Brachydanio rerio (zebra danio), Brachydanio albolineatus (pearl danio), and hybrids formed by their reciprocal crosses was investigated using polyacrylamide disc electrophoresis. Seven esterase isozymes were identified in each species from the unfertilized egg stage to nine days posthatch. Electrophoretic analysis of qualitative changes in enzyme pattern indicated that some esterases were present at all stages of development while other esterases abruptly appeared at a specific stage of morphological differentiation. The esterases of both species were classified on the basis differential substrate and inhibitor specificities. In developing hybrids formed by B. rerio eggs inseminated with B. albolineatus sperm, the maternal isozyme pattern persisted until Stage 17 (gastrulation). Embryonic extracts from Stage 17 onward showed a slow-moving, DFP-sensitive carboxylesterase of paternal origin. In developing hybrids formed by B. albolineatus eggs inseminated with B. rerio sperm, a paternal contribution to the esterase pattern was probably present by the end of gastrulation; esterase activity of distinctively paternal origin was present by Stage 22 (retinal pigmentation) The maternal contribution to the total esterase profile appeared to remain high through hatching. Additional evidence for gene activity at gastrulation was obtained in experiments utilizing actinomycin-D and cycloheximide. Results of exposing embryos of B. rerio to 15 mug/ml of actinomycin-D indicated that transcription of the template RNA coding for cholinesterase occurred during gastrulation or some 20-30 hours prior to the appearance of the isozyme at Stage 22. This template RNA was translated sometime during that 10-hour interval immediately preceding Stage 22.
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PMID:Esterase isozyme patterns in developing embryos of Brachydanio rerio (zebra danio), Brachydanio abolineatus (pearl danio), and their hybrids. 83 81


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