Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The myenteric plexus of the small intestine of five C57BL/6J male 5-month-old mice was investigated in whole-mount preparations of the muscularis externa by Giemsa staining and by the acetylcholinesterase (AChE) histochemical technique. 2. The neuronal density was 20212 +/- 3038/cm2 (mean +/- SEM) in the duodenum, 21948 +/- 1488/cm2 in the jejunum, and 25048 +/- 2356/cm2 in the ileum. The difference in neuronal density between duodenum and ileum was statistically significant (P < 0.05). The total serosal surface area of the small intestine was about 30.80 +/- 2.90 cm2, and the total number of neurons was estimated at about 690,000. 3. The neuronal cell and nucleus profile areas ranged, respectively, from 23 to 325 microns 2 and from 6 to 95 microns 2 in the small intestine of the mice studied. There were no significant differences in any of the 3 regions in terms of average neuronal cell or nucleus profile areas. 4. For the histochemical demonstration of AChE, the "direct coloring" copper ferrocyanide method was used. AChE-positive nerve fibers were distributed in the myenteric plexus which was formed by a primary meshwork of relatively large nerve bundles and a secondary meshwork of finer nerve bundles. Most of the neurons of the plexus displayed AChE activity in the cytoplasm though the neurons presented different reaction intensities.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Myenteric neurons of the mouse small intestine. Morphometry and acetylcholinesterase activity. 817 25

Accuracy in measurement of plasma free fatty acids (FFA), and therefore prevention of the in vitro lipolysis, is a crucial step to understand the physiologic role of plasma FFA and their relationships in the pathogenesis of important metabolic disorders such as central obesity, insulin resistance, and diabetes mellitus. As lipoprotein triglyceride-fatty acids are elevated in these states, in vitro lipolysis of triglycerides may artifactually increase FFA. Plasma FFA were measured in subjects before and after heparin administration, under different experimental conditions affecting the in vitro activity of lipoprotein lipase (LPL) and hepatic lipase (HL). Paraoxon, a cholinesterase inhibitor neurotoxin known to block plasma lipolytic activity, and preextraction timing and temperature of collection were tested. Paraoxon was required to prevent triglyceride hydrolysis in: a) preheparin plasma allowed to stand at room temperature (21 degrees C) for 2 h, before being frozen at -20 degrees C (FFA = 1817 +/- 291 vs. 698 +/- 66 microEq/l, P < 0.005, mean +/- SEM, without and with paraoxon, respectively); and b) in postheparin plasma immediately stored at -20 degrees C (FFA = 2682 +/- 357 vs. 1299 +/- 150 microEq/l, P < 0.005, without and with paraoxon, respectively). No difference in the FFA level was found in preheparin plasma collected either with or without paraoxon when: a) the samples were placed in ice and immediately assayed; b) the specimens were immediately frozen at -70 degrees C and assayed 60 days later.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Analysis of techniques to obtain plasma for measurement of levels of free fatty acids. 835 49

We examined the effect of pyridostigmine (PY) at a dose of 30 mg orally three times a day on nonspecific bronchial hyperreactivity in ten normal nonsmokers (NNS), ten smokers (SM), and ten mild asthmatics (AS). We conducted a double-blind, placebo-controlled, crossover trial, randomly assigning subjects to receive either placebo (PL) or PY before undergoing bronchoprovocation challenge with eucapnic voluntary hyperventilation (EVH) using dry gas. Compliance with PY was confirmed by measuring red blood cell acetylcholinesterase (Achase) levels during both days of testing. While taking PL, the mean (+/- SEM) falls in FVC and FEV1 after the bronchoprovocation were as follows: NNS, 1.0 percent (+/- 0.6) FVC and 4.3 percent (+/- 1.0) FEV1; SM, 2.4 percent (+/- 1.1) FVC and 2.7 percent (+/- 1.3) FEV1; AS, 5.3 percent (+/- 2.3) FVC and 11.5 percent (+/- 2.8) FEV1. The mean decreases in FVC and FEV1 while taking PY were as follows: NNS, 1.8 percent (+/- 0.7) FVC and 4.3 percent (+/- 0.8) FEV1; SM, 3.8 percent (+/- 1.4) FVC and 5.2 percent (+/- 1.6) FEV1; AS, 4.4 percent (+/- 1.3) FVC and 11.8 percent (+/- 2.8) FEV1. Within each category, using a paired t test to compare the results on each day of testing, no statistically significant differences were noted. Pyridostigmine at the tested dose has no significant effect on nonspecific bronchial hyperreactivity in normal NNS, SM, or AS.
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PMID:The effect of pyridostigmine on bronchial hyperreactivity. 840 96

Growth hormone (GH) plasma levels reflect a balance between stimulation via GH-releasing hormone (GHRH) and inhibition by somatostatin (SS). Steroids influence GH secretion by modulating SS tone. There is a correlation between the diurnal secretion of GH and cortisol (CORT). Pyridostigmine, the acetylcholinesterase inhibitor, increases cholinergic tone, inhibits SS release and increases the release of GH. We investigated the influence of CORT on pyridostigmine-induced GH responses by testing subjects at 9.00 and 14.00 h. Basal (mean +/- SEM) CORT levels at 9.00 and 14.00 h were 251.5 +/- 18.4 nmol/l and 142.7 +/- 6.7 nmol/l, respectively. Pyridostigmine-induced GH responses were greater at 9.00 h than at 14.00 h (8.7 +/- 1.5 mU/l; 3.0 +/- 1.0 mU/l, respectively, [ p < 0.001]). A positive correlation between CORT and delta GH values was demonstrated (p < 0.0004).
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PMID:Time dependency of pyridostigmine-induced growth hormone response. 873 43

The disposition kinetics of fenvalerate were studied in goats after dermal application of 100 ml of 0.25% (w/v) solution. The insecticide persisted in the blood for 72 h. The mean (+/- SEM) Vd(area) and apparent t 1/2 (beta) were 9.92 +/- 1.44 L/kg and 17.51 +/- 2.65 h, while the AUC and ClB values were respectively 82.15 +/- 7.40 micrograms h/ml and 0.56 +/- 0.05 L/(kg h). Four days after the dermal application, the highest concentration of fenvalerate residues was found in the adrenal gland, followed by the biceps muscle, omental fat, liver, kidney, lung and cerebrum in that order. Fenvalerate caused hyperglycaemia but had no effect on serum protein and cholesterol levels. Serum acetylcholinesterase activities were increased after 24 h but were below the initial values from 48 to 120 h.
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PMID:The disposition kinetics and residues of fenvalerate in tissues following a single dermal application to black Bengal goats. 873 25

The effect of methantheline, a quaternary ammonium compound, on the reactivation by HI 6 of soman-inhibited human erythrocyte acetylcholinesterase (AChE) was investigated in vitro using purified human erythrocyte AChE or washed human erythrocytes. Methantheline itself was found to be a mixed competitive/non-competitive inhibitor of AChE (Kii 360 +/- 70 mumol/l; Ki 240 +/- 10 mumol/l). In all experiments the enzyme was first inhibited by soman for 30 min under conditions preventing ageing (pH 10.0 degrees C) and then ageing was allowed by changing the pH to 7.3 and the temperature to 37 degrees C. Methantheline addition (0.36 or 3.6 mmol/l) at the start of ageing increased the portion of AChE which could be reactivated by HI 6 (0.32 mmol/l) added 5 min later, from 24.6 +/- 1.0% (mean +/- SEM) of the original activity to 42.1 +/- 1.8% or 45 +/- 2.9%, respectively. With HI 6 alone, the portion of AChE activity which could be reactivated 25 min after the start of ageing decreased rapidly with the delay of the oxime addition (100% of the original activity at immediate addition), the half-life being approximately 2.5 min. With methantheline alone (0.36 mmol/l) the AChE activity was lower after immediate addition (37% of the original value), but the loss of activity due to the increasing delay of methantheline addition exhibited a similar half-life as with HI 6. Finally, when methantheline (0.36 mmol/l) was added at the start of ageing and HI 6 at various intervals thereafter the half-life of AChE activity loss due to the delay of HI 6 addition at least doubled, compared to incubations without methantheline.
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PMID:Methantheline improves the reactivation by HI 6 of human erythrocyte acetylcholinesterase inhibited by soman in vitro. 875 Sep

Cholinergic agonists are known to potentiate GHRH-induced GH secretion, probably acting via inhibition of hypothalamic somatostatin release. Their effect is reduced in aging and in patients with Alzheimer's disease. This may be the consequence of age-related cholinergic impairment, which, in turn, could cause somatostatinergic hyperactivity leading to GH hyposecretion. As in Down syndrome (DS) neural alterations have been reported similar to those in aging, including cholinergic impairment, we verified the GH response to GHRH (1 microgram/kg i.v. at 0 min) alone or combined with pyridostigmine (PD), a cholinesterase inhibitor (60 and 120 mg, respectively, in children and adults, orally at -60 min) in 15 DS children (13.5 +/- 0.6 years) and in 11 DS young adults (24.0 +/- 1.2 years). Fifteen normal children (11.9 +/- 0.5 years), 15 normal adults (27.3 +/- 0.9 years) and 16 normal elderly (76.3 +/- 1.5 years) were studied as controls. IGF-I levels showed an age-related reduction both in DS (children vs. adults, mean +/- SEM:354.8 +/- 44.9 vs. 204.4 +/- 29.4 micrograms/l, p < 0.02) and in controls (normal children vs. normal adults vs. normal elderly:281.4 +/- 36.3 vs. 175.4 +/- 11.2 vs. 72.5 +/- 6.6 micrograms/l, p < 0.001). The GH response to GHRH in DS children was higher than in DS adults (areas under curve: 1,197.6 +/- 241.5 vs. 434.4 +/- 83.3 micrograms/l/h, p < 0.01). On the other hand, in normal subjects the GHRH-induced GH rise was similar in children and adults (1,056.2 +/- 128.4 vs. 800.8 +/- 124.5 micrograms/l/h) and both were higher than that in elderly subjects (296.0 +/- 61.0 micrograms/l/h, p < 0.001). PD enhanced the GH response to GHRH both in DS and in normal subjects (p < 0.005). The GH response to PD+GHRH was lower in DS adults than in DS children (1,068.1 +/- 145.7 vs. 1,897.4 +/- 198.8 micrograms/l/h, p < 0.001) as well as in normal elderly subjects with respect to that in normal children and normal adults (832.3 +/- 144.7 vs. 2,172.1 +/- 156.1 and 2,347.6 +/- 322.4 micrograms/l/h, respectively, p < 0.001). The GH response to GHRH alone or combined with PD in DS adults was lower (p < 0.01) than that in normal adults and similar to that in normal elderly subjects. In conclusion, the present data demonstrate that the stimulated GH secretion in DS undergoes an accelerated age-related reduction. They also suggest the existence of a precocious impairment of central cholinergic activity in DS, which, in turn, could cause somatostatinergic hyperactivity and reduced GH secretion.
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PMID:The enhancing effect of pyridostigmine on the GH response to GHRH undergoes an accelerated age-related reduction in Down syndrome. 887 21

The neuropeptide galanin (GAL) is widely distributed in the central and peripheral nervous systems where it often coexists with catecholamines and acetylcholine. Recently we have reported that human GAL (hGAL) in man depresses the release of norepinephrine (NE) and the responses to both assumption of upright posture and insulin-induced hypoglycemia. To gain an insight into the action of hGAL on sympathetic nervous system activity in man, we investigated the effects of a 60-min infusion (80 pmol/kg/min) of hGAL or saline on the release of NE, epinephrine (E) and pancreatic polypeptide (PP) induced by an acetylcholinesterase inhibitor, pyridostigmine bromide (PD), in nine healthy volunteers. PD (120 mg orally) induced a significant rise in plasma concentrations of NE (1.6 +/- 0.04 vs. 1.08 +/- 0.06 nmol/l), E (0.34 +/ 0.05 vs. 0.12 +/- 0.04 nmol/l) and PP (178.06 +/- 33 vs. 37.57 +/- 7.35 pmol/l), whilst it significantly reduced heart rate (HR; 61 +/- 2 vs. 71 +/- 4 beats/min). Changes in plasma levels of PP were determined as an indirect measure of amplification of endogenous cholinergic activity produced by PD. Administration of hGAL blunted the release of NE and PP evoked by PD. The mean (+/- SEM) area under the curve produced by PD of NE (50.05 +/- 3.97 nmol/l.90 min) and PP (8,692.87 +/- 1,724 pmol/l.90 min) was significantly (p < 0.001) reduced by hGAL infusion (2.65 +/- 1.57 nmol/l.90 min and 248.1 +/- 148 pmol/l.90 min, for NE and PP, respectively). hGAL failed to affect significantly the E release evoked by PD. hGAL was able to enhance HR significantly (104 +/- 5 vs. 69 +/- 3 beats/min), and completely prevented the PD-induced slowing of HR. Both PD and hGAL did not alter supine systolic and diastolic blood pressure. We conclude that hGAL significantly reduces the release of NE and PP stimulated by PD-induced enhancement of cholinergic activity. These findings are consistent with a functional interrelationship between GAL and the cholinergic system in man, and may suggest the participation of a cholinergic pathway in the galaninergic modulation of the autonomic nervous system.
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PMID:Acute administration of human galanin in normal subjects reduces the potentiating effect of pyridostigmine-induced cholinergic enhancement on release of norepinephrine and pancreatic polypeptide. 893 Sep 40

We studied the activity of the enzyme pseudocholinesterase (serum cholinesterase) and its sensitivity to inhibition by dibucaine and fluoride in 400 (200 Iranian and 200 Irish) healthy subjects. The results show Irish subjects have significantly higher serum cholinesterase activity than Iranian subjects (7.82 +/- 0.14 vs 5.22 +/- 0.09 u/ml, mean +/- SEM, p < 0.01). Furthermore, the percent of inhibition of enzyme activity by dibucaine (82.19 +/- 0.68 vs 69.29 +/- 0.68) and fluoride (79.90 +/- 70.13 +/- 0.62) was also significantly higher (p < 0.001) in Irish than in Iranian subjects. One subject (Iranian) with very low pseudocholinesterase activity and a dibucaine number below 20 (atypical) had a history of apnoea following succinylcholine (suxamethonium). These data indicate that the frequency of atypical and heterozygote genes for cholinesterase activity leading to prolonged apnoea is much higher in Iranian than Irish populations. This study emphasises the importance of ethnic pharmacology.
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PMID:Ethnic differences in the frequency distribution of serum cholinesterase activity. 905 23

Acetylcholine (ACh) was detected in the blood and plasma of beagle dogs using a specific, sensitive radioimmunoassay. The mean basal ACh contents in the blood and plasma of beagle dogs were 451 +/- 65 and 83.5 +/- 12.3 pg/ml (+/- SEM, n = 7), respectively, and were lower than the contents in humans reported previously by our laboratory. Oral administration of KW-5092 (10-30 mg/kg), a gastroprokinetic agent with acetylcholinesterase (AChE) inhibitory and ACh release enhancing activities, caused a dose-dependent increase in the ACh content of both the blood and plasma, as well as several behavioral side effects due to peripheral cholinergic stimulation. The size of the increase in the plasma ACh content at each dose of KW-5092 was greater than that in the blood, indicating that KW-5092 caused the increase in the blood ACh content through elevation of the plasma ACh content, by inhibition of AChE and facilitation of ACh release. These results demonstrate that the blood ACh of beagle dogs is present mainly in the blood cells and to a lesser degree in the plasma, and that KW-5092 increased the blood ACh content mainly by increasing the plasma ACh concentration.
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PMID:Oral administration of KW-5092, a novel gastroprokinetic agent with acetylcholinesterase inhibitory and acetylcholine release enhancing activities, causes a dose-dependent increase in the blood acetylcholine content of beagle dogs. 914 9


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