Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.8 (cholinesterase)
 12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 75 cases of histologically verified liver cirrhosis the plasma amino acids were determined by ion exchange chromatography and the results were correlated with different liver function tests as prothrombin time, pseudocholinesterase, serum albumin, GOT, bilirubin and venous ammonia. Out of these parameters prothrombin time, pseudocholinesterase and serum albumin significantly correlated with the sum of branched-chain amino acids and with the Fischer's quotient (molar ratio of branched-chain and aromatic amino acids). Methionin and aromatic amino acids inversely correlated with these parameters, additionally methionin positively correlated with bilirubin and GOT. By comparing plasma amino acid levels in cirrhotics without and with hepatic encephalopathy (grade 3 or 4) no significant differences were found. "Fischer's quotient" showed an overlap in patients with and without encephalopathy. Therefore the precipitation of hepatic encephalopathy is not fully explained by the changes in plasma amino acids. Therapeutic administrations of specially mixtures of amino acids with a high content in branched-chain and a low content in aromatic amino acids correct the plasma amino inbalance for a short time and improves hepatic encephalopathy.
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PMID:Plasma amino acids in hepatic encephalopathy. 29 Jul 44

D(-)S-and L(+)R-tropinoylcholines were synthesized and their antagonisms to acetylcholine (ACh) were studied at muscarinic receptors (guinea-pig longitudinal ileal muscle), acetylcholinesterase (AChE) and pseudocholinesterase (ChE). Tropinoylcholines were reversible competitive antagonists at muscarinic receptors. D(-)S-tropinoylcholine exhibited a higher affinity as an antagonist at muscarinic receptors than the L(+)R-isomer. ONE MOLECULE OF THE ANTAGONIST COMPETES WITH ONE MOLECULE OF THE AGONIST AT EACH MUSCARINIC RECEPTOR SITE. Tropinoylcholines were competitive inhibitors of AChE. L(+)R-tropinoylcholine exhibited a lower K1 and a higher affinity for AChE. Therefore, muscarinic receptors were stereospecific for the D-configuration, whereas AChE was stereospecific forthe L-configuration of tropinoylcholine. Tropinoylcholines were week agonist at nicotinic receptors (frog rectus abdominis); they were substrates of ChE at low concentrations, but they inhibited ChE partially at high concentrations. L(+)R-tropinoylcholine had a lower apparent Km and a higher affinity than its isomer. Therefore, the esteratic site of ChE is possible stereospecific for the L-configuration of tropinoylcholine. Both tropinoylcholines were mixed inhibitors (competitive and noncompetitive) of ACh hydrolysis by ChE. The results imply that the tropinoylcholines interact at a second site as well as the esteratic site.
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PMID:Relationships between the chemical structure and pharmacological activities of D(-)S-and L(+)R-tropinoylcholines at cholinergic sites. 30 65

We have previously shown that non-proliferating human T- but not B-lymphocytes contain demonstrable amounts of acid alpha-naphthyl acetate esterase (ANAE). The usefulness of this histochemical marker for the diagnosis and classification of malignant lymphoid tumors was investigated by use of a panel of established normal and malignant human haematopoietic cell lines and fresh biopsy cells from malignant lymphomas and myelomas. The results showed that not only the T-cell derived acute leukaemia lines, but also histiocytic lymphoma and myeloma lines and some of the lymphoma (Burkitt and lymphocytic) and non-neoplastic lymphoblastoid cell lines with B-cell surface markers expressed strong ANAE reactivity. Some but not all of the immunoglobulin producing myeloma and lymphocytic lymphoma biopsies were ANAE-positive. Inhibition experiments with sodium fluoride and E-600 demonstrated that although the T-lymphocyte specific esterase is predominantly of 'A'-type, the malignant lines contain also non-specific 'B' esterase and pseudocholinesterase. As the presence of the various esterases did not demonstrate any specific distribution pattern among he haematopoietic cell lines of different origin, we concluded that the ANAE marker is no longer T-specific when malignant lymphoid cells are considered, and that the usefulness of this marker in routine diagnostic work therefore is limited.
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PMID:Presence of alpha-naphthyl acetate esterase activity in human haematopoietic cell lines and in fresh biopsy specimens of lymphoma and myeloma. 30 88

Variations of plasma cholinesterase activity were studied in eight patients with end stage liver disease having orthotopic liver transplantation and five other patients with hepatic cirrhosis undergoing surgical procedures. Serum cholinesterase activity was found to be below normal limits in every patient, even more so in those having hepatic homotransplantation, probably because of the greater severity of their disease. Blood transfusions increased pseudocholinesterase activity to normal or nearly normal levels; but only after successful transplantation did these levels remain within normality, thus suggesting that the homografts promptly assume production of the serum enzyme.
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PMID:Changes of plasma cholinesterase activity during orthotopic liver transplantation in man. 32 8

The introduction of the new long acting local anaesthetics, bupivacaine and etidocaine, has stimulated an expansion of interest in regional anaesthesia, particularly for obstetrical applications and pain therapy. System toxicity following injection of local anesthetics occurs albeit infrequently, and tentative correlations have been made between the onset of CNS and cardiovascular effects and circulating drug concentrations in both adults and neonates. Amongst other factors, interpretation of these relationships depends upon blood distribution and plasma binding of the agents, sampling sites and acid-base balance. The disposition kinetics and placental transfer of the amide type agents have been well characterised. In adults their clearance is almost entirely hepatic but in neonates an increase in the renal component is, in part, a reflection of the immaturity of some of the enzymes responsible for their metabolism. Ester type agents are rapidly hydrolysed by plasma pseudocholinesterase and this has led to a preference for chloroprocaine in some obstetric procedures. Major determinants of the systemic absorption of the agents after perineural administration include their physicochemical and vasoactive properties, perfusion and tissue binding at the site of injection and whether or not adrenaline has been added. In respect of blood drug concentrations achieved after various regional anaesthetic procedures, the margin of systemic safety appears to favour bupivacaine and etidocaine compared to shorter acting analogues such as lignocaine and mepivacaine. The time course of local anaesthetic remaining at the site of injection has been calculated following intravenous regional anaesthesia and peridural block. This has allowed prediction of the local and systemic accumulation of the drugs following contined dosage. Blood concentrations of local anaesthetics after perineural injection are not closely related to age, weight or pregnancy but may be influenced by diseases associated with haemodynamic changes and by other drugs given at or around the time of regional blockade.
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PMID:Clinical pharmacokinetics of local anaesthetics. 38 8

Systemic toxic were encountered in eight of 10,469 patients during or immediately following the intramuscular injection of 4,800,000 units of procaine penicillin G for the treatment of gonorrhea. Fear of imminent death, visual and auditory disturbances, violent combativeness, confusion, disorientation, and restlessness, disturbance in taste, cardiovascular changes, and grand mal seizures are the principal manifestations; these usually subside in two to 10 minutes spontaneously or after treatment. Symptoms and signs closely parallel systemic toxic reactions to local anesthetics. Pharmacokinetic analysis in dogs using 14C-procaine and 14C-procaine penicillin G showed rapid distribution of labeled drugs from plasma to cerebrospinal fluid for the intravenous as compared to the intramuscular route of administration. The animal studies were consistent with the hypothesis that the inadvertent intravenous administration of procaine penicillin G is responsible for the systemic toxic reactions. Plasma procainesterase (pseudocholinesterase) activity was assayed with an ultraviolet spectroscopic method. Substrates were procaine and procaine penicillin G. The plasma procainesterase activity of patients who had experienced systemic toxic reactions was significantly decreased as compared to that of controls, an observation not previously reported.
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PMID:Systemic toxic reactions to procaine penicillin G. 41 9

A baby born after a cesarean section experienced transient respiratory depression. The mother had a postsuccinylcholine apnea caused by homozygosity for the atypical allele for serum pseudocholinesterase; the baby was heterozygous for this allele and the usual allele for serum pseudocholinesterase. The possible relationship between the genotype of the baby and the respiratory difficulty at birth is raised.
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PMID:Transient respiratory depression of the newborn. Its occurrence after succinylcholine administration to the mother. 46 36

Contrary to an earlier report that metronidazole exhibited anticholinesterase activity on isolated organ preparations, a direct spectrophotometric assay was unable to demonstrate any significant inhibition of either true or pseudocholinesterase activity in the presence of this drug. The related nitroimidazole, misonidazole, was also found to be inactive when tested in this system. This report demonstrates that the clinical neurotoxicity of these two compounds cannot be attributed to any direct effect on the cholinesterase enzymes.
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PMID:Evaluation of the anticholinesterase activity of metronidazole and misonidazole. 46 96

Acetylcholinesterase (Ache) and pseudocholinesterase (BUche) activities were studied quantitatively in healthy skin by spectrophotometric methods and qualitatively by polyacrylamide gel electrophoresis. The results were compared to those obtained in plasma. The substrates used to reveal enzyme activities were acetylthiocholine (ATC) iodide and butyrylthiocholine (BTC) iodide, respectively. A linear relationship exists between the values of BUche and Ache activities in plasma and those in skin. Six isoenzymes of different electrophoretic mobility were observed in the skin. One of them, which is never found in plasma extracts, appears to be specific to the skin. On gradient gel electrophoresis, with both substrates (ATC and BTC), a single band of enzyme activity, corresponding to a molecular weight of 600,000 was observed. These results suggest that in the skin there is only one enzyme, most probably butyryl cholinesterase, which cleaves BTC somewhat faster than ATC. This methodology, when applied to the study of dermatoses in which abnormalities of cutaneous nerve terminals are suspected, should furnish precise functional pathophysiological details.
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PMID:Cholinesterases isoenzymes: a comparative study in the skin and plasma. 46 77

Histochemical studies have been made on changes in true cholinesterase and pseudocholinesterase in mammalian ontogenesis. It was found that at early ontogenetic stages the enzymes are located mainly in deep layers. In rabbits, early accumulation of the true cholinesterase takes place; evident maximum of the reaction was found directly over the fibres of the cortical white matter during the last days of foetal development and in newborn animals. Accumulation of pseudocholinesterase in myelinating fibers begins at the 7-10th day. In the cortex of human foetuses, evident heterochronous accumulation of cholinesterase was noted, since the enzyme was concentrated mainly in the occipital and frontal parts of the isocortex.
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PMID:[Histochemical study of cerebral cortex cholinesterases during early mammalian ontogeny]. 47 96


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