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 novel combination of supercritical fluid extraction (SFE) with an enzyme assay system has been used to screen meat products to detect the presence of pesticides. Analytes are collected in water by expanding supercritical carbon dioxide to atmospheric pressure through a restrictor and into an aqueous phase. The solution is then tested for the presence of pesticide residues by enzyme assay. Two experimental approaches have been used. Alachlor-fortified lard and bovine liver were monitored by static SFE coupled with an enzyme immunoassay. SFE of carbofuran-fortified frankfurters was coupled with an enzyme assay based on cholinesterase inhibition. A major benefit of the SFE/enzyme assay technique over conventional screening techniques is that the analyst is not exposed to organic solvents.
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PMID:Supercritical fluid extraction/enzyme assay: a novel technique to screen for pesticide residues in meat products. 175 8

This project was designed to titrate the influence of pyridostigmine injected intraarterially on pulmonary resistance and gas exchange in pigs and dogs. Pyridostigmine at 1 mg/kg reduced red blood cell cholinesterase activity 28-35% that was not significantly reduced further with doses up to 9 mg/kg. Plasma cholinesterase was reduced by 80% in the dog and 40% in the pig with 1 mg/kg of pyridostigmine and with 3 mg/kg it was reduced to 40% in the pig and 10% in the dog. Higher doses had no further significant effect. Breathing resistance (cm H2O/l/s) in the pig was doubled as a linear function with 9 mg/kg pyridostigmine. In the dog, breathing resistance went to a maximum of 8 cm H2O/l/s from a control value of 1 cm H2O/l/s with 3 mg/kg of pyridostigmine but did not go higher with doses up to 9 mg/kg. PaO2 was reduced by approximately 20% in the pig and 15% in the dog with pyridostigmine doses of 6-9 mg/kg. These experiments indicate that significant alterations in pulmonary function do not occur until acute dosages in the range of 3-6 mg/kg are reached. Furthermore, acute administration of large doses of pyridostigmine results in salivation and gastrointestinal stimulation well in advance of any impairment of respiratory function.
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PMID:Influence of anticholinesterase on distribution of ventilation and gas exchange. 178 Mar 37

The neurotoxin N-methyl-D-aspartate was used to induce selective bilateral neuronal loss in the entorhinal cortex, in order to model one aspect of the neurodegeneration observed in Alzheimer's disease, Down's syndrome and aging. Lesioned, sham-lesioned and intact control rats learned a reference memory task involving a brightness discrimination for water reward. Rats were trained over 1 week until reaching criteria and tested for retention after a 10-day interval. Lesioned rats showed impaired retention compared to shams and controls, but were able to reacquire the task. Anatomical analysis confirmed excitotoxic lesions of the entorhinal cortex, and showed collateral sprouting of acetylcholinesterase-stained fibers into the outer molecular layer of the dentate gyrus, indicating denervation plasticity in the hippocampus. This functional anatomical study of the entorhinal cortex demonstrates the importance of the entorhinal cortex in memory retention, and raises the possibility that functional deficits in certain neurodegenerative diseases may be modeled by partial neuronal loss in the entorhinal cortex.
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PMID:Excitotoxic lesions of the rat entorhinal cortex. Effects of selective neuronal damage on acquisition and retention of a non-spatial reference memory task. 181 Jun 24

The effects of 9-amino-1,2,3,4-tetrahydroacridine (tacrine), an active acetylcholinesterase inhibitor, on cycloheximide- and basal forebrain (BF) lesion-induced memory deficit in the water maze and passive avoidance task were investigated. While cycloheximide (1.5 mg/kg, s.c.) produced amnesia in the passive avoidance task, chronic administration of tacrine (1, 3 and 10 mg/kg, once a day for 1 week) improved the amnesia. BF lesion produced amnesia in both the water maze and passive avoidance tasks. Chronic tacrine (0.1-3 mg/kg, passive avoidance task, or 0.3 mg/kg, water maze task, once a day for 1 week) improved BF lesion-induced amnesia in the passive avoidance and water maze tasks. These results suggest that tacrine may be useful for senile dementia.
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PMID:The effect of tacrine (THA) on cycloheximide- and basal forebrain lesion-induced memory deficit in rats. 181 59

It was found that acetylcholine (ACh) at the concentration of 10(-3) M inhibited ADH-stimulated water transport through the wall of amphibian urinary bladder. This effect was suggested to be caused by an interaction of ACh with acetylcholinesterase (AChE) rather than by a stimulation of the M- or N-cholinoreceptor. The inhibitory action of ACh was completely suppressed in the presence of various AChE inhibitors (physostigmine, proserine, armine, Gd-42, acridine-iodmethylate), while an inhibitor of butyrylcholinesterase (BuChE), AD-4, failed to affect it. In accord with this observation the activity of AChE (but not of BuChE) was demonstrated in the urinary bladder epithelium. Since, in addition to the hydrosmotic effects of pituitrine, 8-arginine-vasopressin or oxytocin, ACh blocked also effects of forskolin or cyclic AMP, one may conclude that it acts at some post-cyclic AMP production stage. AChE-dependent inhibition of the ADH-stimulated water transport decreased significantly when the serosal pH was raising from 7.2 to 8.0, but was augmented by serosal acidification (pH 6.8), whereas such pH alterations did not affect the activity of the epithelium AChE. The effect of ACh under consideration was suppressed by adding amiloride (10(-4) M) to the serosal solution. Similarly, the ACh effect was blocked by an inhibitor of Ca-dependent K+ channels, 4-aminopyrdine, which in addition prevented the inhibition of the ADH-stimulated water transport by the serosal acidification. It was noteworthy that some other K+ channel blockers (Ba2+, Cs+, tetraethylammonium, apamine, quinine) did not affect either the water transport or the antipituitrine effect of ACh. In conclusion, we suggest that the inhibitory action of ACh on the ADH-stimulated water transport in the urinary bladder is mediated through the intracellular acidification resulting from ACh interaction with AChE. It is unlikely that the acidification is merely a consequence of the ACh hydrolysis, rather the ACh-AChE interaction induces directly an increase in the proton conductivity of the basolateral membrane of the urinary bladder epithelium.
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PMID:[Acetylcholinesterase and the ADH-dependent transport of water in the amphibian bladder]. 181 71

1. We examined the effect, in rats, of an intraseptal microinjection of fasciculin (FAS), an irreversible peptide acetylcholinesterase (AChE) inhibitor, on a) AChE activity measured in septum and hippocampus, b) 3H-quinuclidinyl benzylate (3H-QNB) and 3H-oxotremorine (3H-OXO) binding to hippocampal cholinergic muscarinic receptors, c) 3H-flunitrazepam (3H-FNZ) binding to hippocampal benzodiazepine receptors as a control for QNB and OXO binding, d) acquisition and retention in three different behavioral paradigms, i.e., water-finding (in which there is concomitant habituation to the apparatus), step-down inhibitory avoidance, and shuttle avoidance. 2. AChE activity in septum decreased 2 days (-66%) and 5 days (-48%) after FAS microinjection; a slight reduction (-35%) occurred in the dorsal hippocampus on day 2 (P less than 0.05; N = 6 per group); no changes in AChE activity were observed in ventral hippocampus on day 2 or day 5. 3. No changes in 3H-QNB, 3H-OXO, or 3H-FNZ binding constants were demonstrable in the hippocampus either 2 or 5 days after intraseptal FAS administration. 4. No changes in training or test session performance in any of the three behavioral situations were observed 2-3 days after the intraseptal microinjection of FAS. 5. The persistent inhibition of septal AChE caused by FAS microinjection into the septum is not sufficient to induce major changes either in hippocampal cholinergic muscarinic receptors, or in the learning or retention of behaviors regulated by the septum and/or hippocampus.
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PMID:Biochemical and behavioral effects of intraseptal microinjection of fasciculin, an irreversible acetylcholinesterase inhibitor. 182 65

Previous work in our laboratory has shown that the intradentate administration of colchicine produces time-dependent behavioral and neurochemical changes. Deficits in learning and memory and alterations in the signal transduction process for the cholinergic muscarinic receptor have been observed up to 12 weeks after colchicine treatment. To study the long-term effects of colchicine administration on cognitive function and the cholinergic system, 6 month-old male, Fischer-344 rats were injected with 2.5 micrograms of colchicine bilaterally in the dorsal and ventral hippocampus. Twelve months later the animals were tested for the acquisition of a spatial reference memory task in the Morris water maze for 8 days, with 4 trials of 60 seconds each day. At the completion of the behavioral testing, one set of rats from each treatment group was used for histochemical studies. The remaining animals were sacrificed, the hippocampi removed and used for the estimation of receptor-stimulated turnover of phosphoinositides (Pl). [3H]-inositol was incorporated into the hippocampal slices, and various receptor agonists (carbachol, norepinephrine, serotonin) used to stimulate Pl turnover in the presence of lithium. A significant deficit in acquisition in the water maze was observed in animals 1 year after colchicine administration. Neurochemical studies showed an increase in carbachol-induced Pl metabolism in the rat hippocampus 1 year post-lesion with colchicine. However, in contrast to results obtained 12 weeks after lesioning, no significant changes were observed in norepinephrine or serotonin-induced Pl metabolism 1 year after lesioning. Pirenzepine, a M1 receptor antagonist, produced a greater degree of inhibition (62%) in lesioned animals as compared to the age-matched controls (20%). Increased staining for acetylcholinesterase was found in the hippocampus of treated rats. This effect is similar to that observed 12 weeks after lesioning. These data suggest that the effects of colchicine on the cholinergic system are long-lasting and can be observed a year after treatment.
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PMID:Long-term behavioral and neurochemical effects of intradentate administration of colchicine in rats. 184 22

A ten-year-old boy with paroxysmal nocturnal hemoglobinuria (PNH) is described. Although hemolytic anemia was evident, Ham's test was negative and the erythrocyte acetylcholinesterase (ACHE) activity was normal at the first admission. The diagnosis of hemolytic anemia of unknown etiology was made. Methylprednisolone pulse therapy was started, but could not prevent the hemolytic crises associated with infections. Twelve months later Ham's test turned positive and ACHE activity decreased. The diagnosis of PNH was confirmed. As the disease is insidious in onset, we emphasize that a high index of suspicion and Ham's test and sucrose water test repeated at regular intervals are required to avoid missing the diagnosis.
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PMID:A case report of paroxysmal nocturnal hemoglobinuria in a child. 185 21

We investigated the effect of starvation for 24 hr and subsequent refeeding for 12 hr on the circadian rhythms of 39 hematological and clinico-biochemical parameters, and water intake of F344 rats. The rats scarcely drank any water during the starvation period, but subsequently their intake of water were normal, even in the light period. During starvation, 12 parameters such as serum levels of alkaline phosphatase activity and PaCO2 decreased with time-related and time-related increases of 8 parameters such as the erythrocyte count and cholinesterase activity. During refeeding for 12 hr, almost all these biochemical parameters were normalized, but none of the hematological values except the leukocyte count returned to normal levels. Starvation and refeeding had little affect on the circadian rhythms of others.
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PMID:Effect of starvation and refeeding on the circadian rhythms of hematological and clinico-biochemical values, and water intake of rats. 191 7

Various 4-arylthiomethyl-2-oxo-1,3-dioxole derivatives IIIa-o were synthesized. Their hydrolysis rates by arylesterase (EC 3.1.1.2) and cholinesterase (EC 3.1.1.8) in human serum were evaluated. Some of them were not hydrolyzed by cholinesterase, but were hydrolyzed easily by arylesterase. Among the substrates, sodium 4-((5-methyl-2-oxo-1,3-dioxol-4-yl)methylthio)benzenesulfonate (IIIg) was selected for its substrate reactivity toward arylesterase and its good water solubility. In addition, neither aliesterase (EC 3.1.1.1), acetylesterase (EC 3.1.1.6) nor cholesterol esterase (EC 3.1.1.13) hydrolyzed the compound. IIIg is thus concluded to be a specific substrate for arylesterase. Our assay system for serum arylesterase using IIIg can be readily applied to an automatic analyzer in the diagnosis of liver cirrhosis.
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PMID:2-Oxo-1,3-dioxoles as specific substrates for measurement of arylesterase activity. 193 62


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