Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.1.8 (cholinesterase)
12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The intrinsic innervation of the kidney in Rattus rattus rufescens (Indian black rat) has been studied by cholinesterase technique, under various temperatures, incubation periods and different pH values. The percentage of myelinated nerves was rather high in the medulla region, whereas the non-myelinated nerves dominated in association with the uriniferous tubules and their branches, glomerulus and renal vein in the cortex region. Periarterial AChE-positive ganglia were recorded in the medulla region. The perivenous and periglomerulus plexuses were formed by the non-myelinated nerves and their branches.
...
PMID:Neurohistological observations on the kidney of Rattus rattus rufescens (Indian black rat) as revealed by cholinesterase technique. 8 95

Presence and the relation of the nerve endings with associated structures in the lund of Rattus rattus rufescens (Indian black rat) and Francolinus pondicerianus (grey partridge or safed teeter) has been studied by cholinesterase technique. Dot, plate, and Vater pacini Corpuscles like nerve endings in the lung of Rattus and dot, and bulb like nerve endings with axis cylinder covered with myelinated sheath in the lung of Francolinus were recorded. The nerve endings were AChE-positive.
...
PMID:Histochemical study on the nerve endings in the lung of Rattus rattus rufescens and Francolinus pondicerianus. 61 95

The present investigation was undertaken to study the innervation and acetylcholinesterase (AChE) distribution in the adrenal gland of Rattus rattus rufescens (Indian black rat) by cholinesterase technique. The percentage of myelinated nerves in the cortical zone (cortex) and medulla zone was high. AChE-positive and multipolar ganglia on the outer medulla region, and the ganglia and nerve cells, arranged in chain-like fashion in the chromaffin tissue, were recorded. AChE activity was marked in the cortical zone (in the form of spots) and in the medulla zone (in the form of white and black grains).
...
PMID:Neuro-histochemical study of the adrenal gland of Rattus rattus rufescens (Indian black rat) as revealed by cholinesterase technique. 67 53

An acetylcholinesterase (AChE) activity and a cholinesterase (ChE) activity were localized in mammalian kidneys, using a modified histochemical method of Koelle. The animals studied were mouse, hamster, cat, rat, and guinea pig. The kidneys were excised after in situ perfusion and fixation to eliminate AChE and ChE activities of blood. We carried out a relatively long incubation (up to 4 h) to detect weak AChE and ChE activities in the tissue. The differences in enzymatic activities in the kidneys from these 5 animals were important. The AChE activity was localized in the glomerulus (mouse, hamster, cat, and rat) and in the tubule (mouse, hamster, and rat). The ChE activity was also localized in the glomerulus (mouse and rat) and in the tubule (mouse and cat). An important nonspecific esterase activity was observed in the tubules of rat, guinea pig, and cat. In the thin segment of the loop of Henle, except of cat kidney, no esterase activity at all was observed. Electron microscopy revealed that, in the mouse kidney, both AChE and ChE activities were localized in the endoplasmic reticulum of glomerular endothelial cells and mesangial cells. (An AChE activity was localized mainly in mesangial cells, while ChE activity was localized mainly in endothelial cells). AChE and ChE activities were also localized in the endoplasmic reticulum of tubule cells.
...
PMID:A histochemical localization of acetylcholinesterase and cholinesterase activities in mammalian kidneys. 309 Aug 31

Investigating the possibility that acetylcholinesterase (AchE) and butyrylcholinesterase (BuChE) are regulated in a coordinated manner, we have examined the natural variation in activity of these two enzymes in several tissues of adult male Sprague-Dawley, Fischer-344, and Wistar-Furth rats. Both enzymes varied greatly in mean activity among brain, diaphragm, atria, serum, superior cervical ganglia, and liver. In Sprague-Dawley rats there were also large individual variations with up to a fivefold range of AChE activities and up to a 100-fold range of BuChE activities in a given tissue. Individual variations in cholinesterase activities appeared to be smaller in the inbred Fischer-344 or Wistar-Furth rats. Experiments with internal standards of partially purified AChE and BuChE indicated that the individual variations probably reflected differences in the intrinsic content or specific activity of the tissue enzymes. Comparison of the AChE activities in different tissues of a given group of rats failed to reveal statistically significant correlations in any strain (i.e., the relative activity of any one tissue was no guide to the relative activity of any other tissue in the same rat). This result indicates that the regulation of AChE is tissue-specific. By contrast, BuChE activity showed highly significant correlations among the majority of the tissues examined in the Sprague-Dawley rats, implying that widely dispersed factors can affect the regulation of this enzyme. Body-wide regulation is not necessarily the rule, however, since only a single tissue pair in the inbred Fischer rats and none of the pairs in the Wistar-Furth rats showed significant correlations of BuChE activity. In general, AChE and BuChE activities were not correlated with each other to a statistically significant degree. We conclude that the control of these enzymes normally involves different mechanisms and is strongly affected by the genetic background of the sample population.
...
PMID:Divergent regulation of acetylcholinesterase and butyrylcholinesterase in tissues of the rat. 706 57

Cholinomimetic agents increase blood pressure and heart rate via central muscarinic cholinoceptors in various species. It was reported that i.c.v. injection of the muscarinic M1 and M3 cholinoceptor selective antagonist, 4-DAMP (4-diphenylacetoxy-N-methyl-piperidine methiodide), inhibited the pressor response to physostigmine, while the M1 selective antagonist, pirenzepine, was ineffective. In the present study, the involvement of muscarinic M2 cholinoceptors in central cholinergic hypertension and tachycardia was investigated. Physostigmine (10-80 micrograms/kg i.v.), a cholinesterase inhibitor, and oxotremorine (20-40 micrograms/kg i.v.), a direct muscarinic cholinoceptor agonist, caused a dose-dependent increase in blood pressure. Additionally, physostigmine induced dose-dependent tachycardiac responses. I.c.v. administration of the muscarinic M2 cholinoceptor antagonists, AF-DX 116 and methoctramine, inhibited both physostigmine (60 micrograms/kg) and oxotremorine (20 micrograms/kg)-induced pressor responses at their lower doses used in this study (100 nmol/rat and 10 nmol/rat, respectively). These findings indicate the partial involvement of postsynaptic muscarinic M2 cholinoceptors. The higher doses of the antagonists (AF-DX 116,300 nmol/rat and methoctramine 30 nmol/rat) potentiated the blood pressure increase due to physostigmine but did not affect that due to oxotremorine. The physostigmine-induced tachycardiac responses were influenced similarly by these antagonists. These results suggest the presence and tonic influence of presynaptic inhibitory muscarinic M2 cholinoceptors.
...
PMID:Central muscarinic M2 cholinoceptors involved in cholinergic hypertension. 811 94

A choline amperometric biosensor was assembled and used to measure the anticholinesterase activity due to compounds (which have the property to inhibit cholinesterase enzymes) present in water samples. This parameter can be used as a 'toxicological index', defined as the amount of compound which causes a certain percentage of cholinesterase inhibition equivalent to a known amount of a reference compound causing the same percentage inhibition. The organophosphorus insecticide Paraoxon, which has proved to be a strong inhibitor of cholinesterase enzymes, was chosen as the reference compound. The analysis was carried out by monitoring the decrease of cholinesterase activity in the presence of a pesticide and a substrate specific for the enzyme whose reaction produces choline. The decrease in choline production was measured by the choline sensor and correlated to the concentration of anticholinesterase compound present in the solution. Parameters such as buffer, pH, temperature and incubation time were optimized. The rate constant Ki was calculated experimentally for Paraoxon and used in the anticholinesterase activity measurements at different fixed incubation times. The probe was calibrated with different standard solutions of Paraoxon. The effect of Paraoxon and heavy metals on the choline probe was evaluated. This probe was then used for the determination of anticholinesterase activity of some organophosphorus pesticides, and heavy metals in spiked waters. Samples were also analysed by liquid/liquid extraction and GC determination. Results seem to correlate with acute toxicity expressed as LD50 (oral, rat). Analysis of water samples from different sources in central Italy were analysed for total anticholinesterase activity (TAA) and compared with a reference procedure.
...
PMID:Anticholinesterase activity measurement by a choline biosensor: application in water analysis. 839 50

Adult male albino rats were orally infected with Trichinella spiralis (T. spiralis) larvae (400 larvae/rat). The cholinesterase (ChE) activity was then determined in the serum, brain, spinal cord, liver, stomach, intestine, heart, diaphragm and gastrocnemius muscle of the infected rats at different time intervals (15, 30, 45, 60 and 90 days) after infection. The enzyme activity was inhibited at all the time intervals in the brain, liver, heart and diaphragm while it increased progressively in the serum. In the spinal cord the ChE activity was inhibited at 15, 30 and 45 days postinfection but was markedly increased thereafter. In the intestine, stomach and gastrocnemius muscle the enzyme activity was generally increased. These alterations in ChE activity may be due to the stress effect due to the presence of the larvae in the tissues and/or the toxic effect or their metabolites.
...
PMID:Studies on tissue cholinesterase in experimental trichinosis in albino rat. 1. Effect of T. spiralis infection. 848 86

The objectives of this study were to investigate the protein binding and the in vitro hydrolysis rate of clevidipine and its enantiomers in the rat, dog and man in different biological matrices including blood and plasma from volunteers with deficient pseudocholinesterase activity. The in vitro half-life in blood was 0.6 min (rat), 15.7 min (dog) and 5.8 min in man with normal pseudocholinesterase activity, while the half-life was approximately 9 min in blood from pseudocholinesterase deficient volunteers. The half-life in pseudocholinesterase deficient volunteers was prolonged, although the hydrolysis rates in blood and red blood cells (RBC) were much higher than in plasma, suggesting that esterases located in the RBC are most important in the blood metabolism of clevidipine. A decrease in temperature increased the half-life of clevidipine in blood, whereas dilution of the blood did not affect the in vitro half-life of clevidipine. The albumin concentration affected the hydrolysis rate of clevidipine in RBC suspended with saline. The protein binding of clevidipine and its enantiomers was >99.5% in plasma from all species studied. There was a difference between the free fractions of S- and R-clevidipine in man, 0.43 and 0.32%, respectively, and this stereoselective binding might be the reason for the 10% difference between the in vitro hydrolysis rates of the enantiomers in human blood.
...
PMID:In vitro hydrolysis rate and protein binding of clevidipine, a new ultrashort-acting calcium antagonist metabolised by esterases, in different animal species and man. 1007 76

Tacrine, a reversible cholinesterase (ChE) inhibitor, lowers body temperature by increasing cholinergic activity in the hypothalamus. Its hypothermic effect was significantly greater in female than in male rats at doses of 2.5-12.5 mg/kg. Gonadectomy increased the maximum fall in temperature after tacrine (5 mg/kg) from 1.92+/-0.16 to 2.59+/-0.13 degrees C in males and from 2.96+/-0.25 to 3.63+/-0.27 degrees C in females. Testosterone (10 mg/rat) rats significantly reduced the hypothermia in gonadectomised males and females and abolished the gender difference. Adrenalectomy increased the fall in temperature after tacrine (5 mg/kg) to 2.92+/-0.15 degrees C in males and 4.18+/-0.24 degrees C in females. The sex difference that remained was abolished by four daily injections of corticosterone (5 mg/kg). Plasma ChE can bind tacrine thereby lowering the amount available to the brain. Ovariectomy decreased plasma ChE activity from 2.27+/-0.24 to 1.66+/-0.14, while adrenalectomy reduced it to 1.30+/-0.10 (micromoles acetylthiocholine hydrolysed/ml/h). This enzyme activity was unaffected by gonadectomy and adrenalectomy in males. Brain levels of tacrine, (5 mg/kg), 1 h after injection were 2.41+/-0.35 microg/gm in males and 4.97+/-0.57 microg/gm in females. Gonadectomy increased brain levels in males to 4.05+/-0.51 microg/gm and testosterone restored them to 2.64+/-0.3 microg/gm. The hypothermic effect of tacrine was highly correlated to its brain concentration after the hormonal manipulations. It is concluded that steroids can reduce the pharmacological effects of tacrine by interfering with its entry into the brain.
...
PMID:Steroid hormones mediate sex difference in brain levels of tacrine and its hypothermic effect in the rat. 1168 53


1 2 Next >>

---