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 positive influence of L-carnitine administration on postaggression metabolism was investigated. Clinical examinations were executed on three groups of patients K1, K2, K3). Comparable surgical operations like stomach- and intestinal- resections were performed on these groups of patients. During the first three days after operation a nutritional diet (parenteral, standardized hypocaloric) with (K2: 2 g; K3: 4g) and without L-carnitine (K1) was given. The effects of L-carnitine administration were evaluated by the following parameters: free fatty acids (FFS), triglycerides (TG), beta-hydroxybutyric acid (beta-OH-BS), acetacetate (ACAC), blood sugar (BZ), insulin (INS), lactate (LAK), pyruvate (PYR), total protein (GE), cholinesterase (CHE), urea production rate (PU), nitrogen of alpha-aminogroups (alpha-AN), nitrogen balance (NB), catabolic index (KI), BUN-Creatinine-quotient (B/K), total carnitine (GC), free carnitine (FC), acetyl carnitine (AC) and also the ratio between acetyl carnitine and free carnitine (AC/FC) in serum and urine. The results show no statistical significance. But they could lead to the following conclusions: Carnitine obviously reduces the insulin resistance. But it does not influence the post-operative perturbation of glucose-utilization. Carnitine reinforces the utilization of long chain fatty acids and thus improves the energy conversion. Carnitine leads to an earlier positive nitrogen balance. By giving 4 g of carnitine a day, already after three days a repletion of tissue deposits is possible, and a dose dependence for carnitine administration exists for the utilization of long chain fatty acids and the repletion of tissue deposits.
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PMID:[Effect of L-carnitine on post-stress metabolism in surgical patients]. 310 72

The kinetics of cholinesterase enzymatic hydrolysis of carboxylic acid adamantyl derivatives was studied in vitro. The maximal rate of enzymatic hydrolysis in the series of bis-esters was shown to increase on elongation of the distance between ester groups. The maximal hydrolysis rate in the series of bis- and mono-esters decreases on elongation of the distance between ester group and quaternary nitrogen atom. The addition of adamantyl radical to the alcohol part of the molecule of bis- and mono-esters prevents the hydrolysis. The addition of lipophilic radicals to the cationic group of derivatives of mono- and dicarboxylic acids exerts a greater effect on the maximal hydrolysis rate in monoesters than in bis-esters.
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PMID:[Hydrolysis by plasma cholinesterase of complex adamantyl-containing esters]. 323 39

A number of quaternary salts of trans-4-(beta-1-naphthylvinyl)pyridine (NVP) were synthesized and evaluated as inhibitors of the enzymes choline acetyltransferase (ChAT) and acetylcholinesterase (AChE). Structural variations in the side arm attached to the pyridine nitrogen atom demonstrate that an inductive effect is small but significant for activity. Inhibition of ChAT by alkylated derivatives decreases when electron-withdrawing groups are placed in the side chain. Substitution of a methyl group on the pyridine ring only slightly affects activities toward ChAT and AChE. When the pyridinium moiety is replaced by an imidazolium ring, no ChAT inhibition was observed. The imidazolium compound, however, was a weak inhibitor of AChE. For design of affinity columns for purification of ChAT, the data also supports the use of long chain alkylated amide derivatives of NVP.
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PMID:Evaluation of the side arm of (naphthylvinyl)pyridinium inhibitors of choline acetyltransferase. 333 13

Benzoic acid esters of various substituted 2-hydroxyacetamides (glycolamides) were found to be hydrolyzed extremely rapidly in human plasma solutions, the half-lives of hydrolysis being less than 5 s in 50% plasma solutions for some N,N-disubstituted glycolamide esters. The rapid rate of hydrolysis could be largely attributed to cholinesterase (also called pseudocholinesterase) present in plasma. From a study of a variety of substituted glycolamide esters and structurally related esters, the most prominent structural requirement needed for a rapid rate of hydrolysis was found to be the glycolamide ester structure combined with the presence of two substituents on the amide nitrogen atom. A structural similarity of such esters with benzoylcholine, a good substrate for cholinesterase, was put forward. Esters of N,N-disubstituted glycolamides are suggested to be a useful biolabile prodrug type for several carboxylic acid agents. The esters combine a high susceptibility to undergo enzymatic hydrolysis in plasma with a high stability in aqueous solution. Furthermore, as demonstrated with the benzoic acid model esters, it is feasible to obtain ester derivatives with almost any desired water solubility or lipophilicity with retainment of marked lability to enzymatic hydrolysis.
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PMID:Glycolamide esters as biolabile prodrugs of carboxylic acid agents: synthesis, stability, bioconversion, and physicochemical properties. 337 86

The ultrastructural alterations in CA3 pyramidal neurons induced by the irreversible organophosphorus anticholinesterase (OP anti-ChE) pinacolyl methylphosphonofluoridate (soman) and by hypoxia were examined in rat hippocampal slices. During the first 60 min of incubation in control saline, up to 70% of the CA3 pyramidal neurons from slices superfused in control saline showed dilated cisternae of the rough endoplasmic reticulum (ER) or disrupted mitochondria. Fewer cells (10%) displayed heterochromatin clumping. With longer incubations (180 min), the number of cells showing these characteristics declined. During this time, up to 25% of these cells showed indentations in the nuclear envelope. Bath application of saline solutions containing 100 nM soman elicited periodic, spontaneously occurring epileptiform events in the CA3 subfield and substantially reduced (greater than 70%) acetylcholinesterase activity in single slices. The most characteristic ultrastructural alteration observed in response to 100 nM soman (30- to 60-min exposure) was a time-dependent, irreversible increase (up to about 60%) in the number of CA3 pyramidal neurons exhibiting indentations in the nuclear envelope. A morphometric analysis revealed a reversible, soman-induced decrease in the measured nuclear area. To test the hypothesis that these soman-induced alterations were related to hypoxic conditions, the fine structure of CA3 pyramidal neurons was characterized after the control saline was bubbled with nitrogen (95% N2, 5% CO2). In contrast to the effects induced by soman, exposure to nitrogen (15-180 min) caused dilation of rough ER cisternae, created depleted areas within the perikaryon, and produced extensive clumping of heterochromatin. In addition, more CA3 pyramidal neurons showed mitochondrial alterations after exposure to nitrogen than in control or soman-containing saline. Indentations in the nuclear envelope were not observed in response to hypoxia. We concluded that the soman-induced morphological alterations seen in vitro were comparable to those observed in hippocampi from whole animals exposed to sublethal doses of soman. The observations made in this study do not support the hypothesis that the acute alterations induced by soman in the fine structure of CA3 pyramidal neurons were the consequence of hypoxia.
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PMID:Acute ultrastructural alterations induced by soman and hypoxia in rat hippocampal CA3 pyramidal neurons. 339 6

The role of hypothermia in the antihypoxic effects of drugs was examined in the present experiments. The effects of environmentally induced hypothermia and drugs were tested by exposing mice to 100% nitrogen gas for 80 sec and counting the number of survivors. In a series of 68 vehicle control groups, the mean of mice surviving the test was 8.6% (SEM = 1.4). Hypothermia induced by lowering the ambient temperature or by isolating mice for a brief period increased the number surviving hypoxia, and the per cent of animals surviving was linearly related to body temperature. When the effects of drugs were compared to that of hypothermia, several drugs were found which protected mice from hypoxia to a greater extent than hypothermia alone. Active substances included the anticonvulsant drugs phenobarbital, phenytoin, carbamazepine and diazepam, but not primidone. Physostigmine and the muscarinic agonist oxotremorine also caused significant protection, while the effects of nicotine could be completely accounted for by hypothermia. Arecoline had a biphasic, time-dependent effect that may be explained by a combination of muscarinic and nicotinic actions. The effects of the muscarinic agonists are centrally mediated, since they could be blocked by low doses of scopolamine HCl, but not by the quaternary analog scopolamine methyl nitrate. Furthermore, the antihypoxic effect of physostigmine was not mimicked by the peripherally acting acetylcholinesterase inhibitor, neostigmine. These results suggest that some drugs do have protective effects against hypoxia which are independent of drug-induced hypothermia and that these effects may be mediated through the CNS.
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PMID:Protection against hypoxia-induced lethality in mice: a comparison of the effects of hypothermia and drugs. 359 68

F344/N rats and B6C3F1 mice were exposed to 0, 1, 3, or 6 ppm methyl isocyanate by inhalation for 6 hr on 4 consecutive days. Deaths of rats were observed following 3 ppm exposures, and mice died after exposures to 6 ppm. Deaths appeared to be related to severe respiratory distress. Survivors in high dose groups lost weight initially, then gained weight at rates equal to controls throughout a 91-day recovery period. Lung weights increased significantly in male and female rats exposed to 3 ppm, but no persistent changes in brain, kidney, thymus, spleen, liver, or testis weights were seen in either mice or rats. Blood and serum from male and female rats were taken for clinical pathology and hematology assessments on day 7 of postexposure, the day prior to the first observed deaths of these animals. No changes or only slight changes were seen in measures of serum alanine aminotransferase, sorbitol dehydrogenase, alkaline phosphatase, or in blood and brain cholinesterase activities. However, serum creatine kinase increased with dose in both males and females. Blood urea nitrogen, creatinine, and methemoglobin were unchanged. No changes were seen in counts of red blood cells or platelets, or in red cell indices. Hemoglobin concentrations and hematocrits were slightly elevated. No changes were noted in absolute leukocyte counts, but counts of segmented neutrophils increased and lymphocytes decreased.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The toxicity of inhaled methyl isocyanate in F344/N rats and B6C3F1 mice. II. Repeated exposure and recovery studies. 362 27

1. A variety of biochemical measurements were taken periodically in captive northern bobwhite (Colinus virginianus L.), European starlings (Sturnus vulgaris L.), red-winged blackbirds (Agelaius phoeniceus L.) and common grackles (Quiscalus quiscula L.) to determine whether baseline values remain sufficiently stable throughout the year for general clinical use in the absence of concurrent control specimens. 2. Variables included whole blood hematocrit and hemoglobin, plasma lactate dehydrogenase, alpha-hydroxybutyrate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, creatine kinase, butyrylcholinesterase, alkaline phosphatase, glucose, albumin, total protein, creatinine, urea nitrogen, uric acid, cholesterol, and triglycerides, and brain acetylcholinesterase. Butyryl- and acetylcholinesterase were included because of their specific uses in toxicology. 3. Significant seasonal differences were detected for each of the variables except brain acetylcholinesterase in at least one of the species. Significant species differences were detected during at least one season for all of the variables measured. 4. All species were maintained outdoors, but only northern bobwhites came into reproductive condition and showed sex-differences in the clinical variables during their normal breeding season. 5. It was concluded that reference values for the 18 clinical variables measured could be calculated from our data for adult specimens of the species studied, and that results for one species cannot be extrapolated with certainty to any other species. 6. Estimated normal bounds for each of the 18 variables measured by commonly used clinical procedures are presented for reproductively quiescent northern bobwhites, European starlings, red-winged blackbirds, and common grackles.
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PMID:Seasonal variation in diagnostic enzymes and biochemical constituents of captive northern bobwhites and passerines. 366 39

Eight hematologic parameter values, 16 serum biochemical constituents, serum protein fractions and albumin-globulin ratios were determined in blood samples obtained from 879 normal, healthy Beagle dogs of both sexes which had been reproduced and bred in our laboratories. The blood samples were collected from the Beagles that ranged in monthly ages from 1 to 12 and in monthly ages from 13 to 121, which were classified as the adult class. As a result, red blood cell counts, hemoglobin concentrations and packed cell volumes increased with growth. Red blood cell parameters of normal Beagles in our laboratories were rather higher than those in literatures presented by many other researchers. MCV decreased and MCHC increased gradually with age. Total serum protein concentrations increased with growth. alpha 1-1 and alpha 1-2 Globulin fractions descended, but beta 2 and gamma globulin fractions ascended in serum proteins. Alkaline phosphatase activities, inorganic phosphorus concentrations and glucose concentrations decreased conspicuously with growth. Leucine aminopeptidase activities and calcium concentrations decreased slightly. Serum cholinesterase and LDH activities showed a tendency to diminish similarly. Blood urea nitrogen and creatinine concentrations multiplied gradually. Hematologic parameters became almost steady in our 7-month-old dogs or older ones and serum biochemical constituents had a tendency to be stable in our 7- to 9-month-old dogs or older ones in the blood. White blood cell counts, alkaline phosphatase activities, inorganic phosphorus concentrations, glucose concentrations, leucine aminopeptidase activities and calcium concentrations were lowest in the adult class.
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PMID:[Successive changes in the blood composition of experimental normal beagle dogs associated with age]. 408 64

1. The metabolism of the phosphorothionate parathion in vitro was examined by using [(32)P]parathion and microsomes isolated from the livers of various animal species. 2. The major metabolic products of parathion in this system in vitro were identified as diethyl 4-nitrophenyl phosphate (paraoxon), diethyl hydrogen phosphate, diethyl hydrogen phosphorothionate and p-nitrophenol. 3. The reaction leading to the formation of diethyl hydrogen phosphorothionate and p-nitrophenol requires the same cofactors (NADPH and oxygen) required for metabolism of parathion to its active anti-acetylcholinesterase paraoxon. 4. The enzyme activity towards parathion per unit weight of liver is increased some 65-130% by pretreatment of male rats with phenobarbital and 3,4-benzopyrene. 5. The metabolism of parathion is inhibited by incubation in a nitrogen atmosphere and in an atmosphere containing carbon monoxide. Pure oxygen is also inhibitory. These results are discussed in terms of a deficiency of oxygen for maximal activity as well as the lability of some component of the system to oxidation.
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PMID:Studies on the metabolism of diethyl 4-nitrophenyl phosphorothionate (parathion) in vitro. 438 89


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