Plasma Pseudocholinesterase Activity Research Articles

Blood Plasma Pseudocholinesterase as a Potential Biomarker of Autoimmune Diseases

We studied the blood plasma butyrylcholinesterase (BChE, pseudocholinesterase) activity as a potential marker for differentiating such autoimmune pathologies as type 1 diabetes mellitus (DM1), autoimmune thyroiditis (AIT) and rheumatoid arthritis (RA) from diseases having similar symptoms but different etiology. The blood plasma pseudocholinesterase activity was analyzed for patients with different types of diabetes mellitus. We showed its fivefold increase in DM1 compared to the control group, while in the second type of diabetes, which is metabolic pathology, it decreases two times. It was demonstrated that the activity of blood plasma BChE in patients with AIT and RA also increased fivefold compared to the group of patients without autoimmune disorders. Thus, the butyrylcholinesterase activity increases in diseases of an autoimmune nature, whereas in metabolic pathology it has the tendency to decrease; it indicates the adequacy of the selected criterion for the further development of a screening test-system that would allow differentiation of autoimmune diseases from the diseases of another origin, but with similar symptoms.

Neuromuscular pharmacodynamics of mivacurium in adults with major burns

Mivacurium is metabolized by plasma pseudocholinesterase (PChE) enzyme, which is decreased in burns. We tested whether the decreased metabolism of mivacurium due to decreased PChE activity can overcome the pharmacodynamic resistance to non-depolarizing relaxants previously seen in major burns. Thirty adults with 35 (13)% [mean (sd)] burn were studied at 5-91 post-burn days and 31 non-burns matched controls. Mivacurium 0.2 mg kg(-1) was administered as a single bolus. Neuromuscular block was monitored with single-twitch response using TOF-Watch™. Onset time (drug administration to maximal twitch suppression) and spontaneous recovery were measured. Onset time was significantly prolonged in burns when compared with non-burns (115 vs 90 s; P<0.001). The PChE levels were lower in burns [1432 (916) vs 2866 (731) IU litre(-1); P<0.001] and the neuromuscular recovery to 50% of baseline twitch height was prolonged in burns (41 vs 26 min; P<0.001). There was a significant correlation between PChE and time to 50% recovery for the whole group together (r=-0.6; P<0.001). The dibucaine numbers were not different. The prolonged onset time suggests resistance to neuromuscular effects, whereas the prolonged recovery suggests increased sensitivity. This divergent response can be explained by qualitative and quantitative changes in acetylcholine receptor expression causing resistance and decreased PChE activity causing sensitivity. Despite using a relatively large dose of mivacurium (0.2 mg kg(-1)) in the presence of decreased PChE levels, this did not overcome the resistance resulting from up-regulated receptors.

The relation between plasma lipid levels and pseudocholinesterase activity in hypothyroidism.

The relation of plasma lipids and pseudocholinesterase (PChE) activity was studied in rats made hypothyroid by treatment with propylthiouracil (0.05% in drinking water for 28 days) and in hypothyroid patients prior and after L-thyroxine-therapy (1. week 25-50 microg, 2.-4. week 100 microg daily). In rats, thyroid hormone deficiency caused a significant increase in plasma and adipose tissue PChE activity as well as total plasma cholesterol (TC) concentration, and a decrease in plasma triglyceride (TG) concentration. In contrast to rats, thyroid-deficient humans demonstrated a decrease in plasma PChE activity and an increase in both TC and TG, in comparison with euthyroid controls. After one month's therapy with L-thyroxine, reversion of PChE activity and lipid concentrations occurred. The opposite changes of PChE elicited by thyroid hormone deficiency in men and rats are similar to the respective changes in lipoprotein lipase (LPL) activity, observed by other authors. The inverse correlation between both PChE and LPL activity and TG concentration suggests that PChE, similarly to LPL, may be involved in TG hydrolysis.

Markedly Prolonged Paralysis After Mivacurium in a Patient Apparently Heterozygous for the Atypical and Usual Pseudocholinesterase Alleles by Conventional Biochemical Testing

Markedly Prolonged Paralysis After Mivacurium in a Patient Apparently Heterozygous for the Atypical and Usual Pseudocholinesterase Alleles by Conventional Biochemical Testing

Pseudocholinesterase Activity in Human Cerebrospinal Fluid

Pseudocholinesterase (PCHE) activity and dibucaine numbers (DN) in the cerebrospinal fluid (CSF) and plasma of 10 ASA physical status 1 and 2 patients were measured using a kinetic method. CSF had a mean PCHE activity of 0.018 +/- 0.013 unit/ml with a DN of 59 +/- 4. Whereas, PCHE activity and DN in the plasma were 0.960 +/- 0.12 units/ml and 84 +/- 3, respectively. We also measured PCHE activity and DN in the CSF and plasma of 4 patients in whom there was a recent history of intraventricular bleeding. These patients had a CSF PCHE activity of 0.340 +/- 0.07 units/ml (DN = 78 +/- 3) and a plasma PCHE activity of 0.950 +/- 0.10 units/ml (DN = 82 +/- 2). Our data show that there is a low activity of PCHE in CSF, 1/20-1/100th that of plasma. Our data also show that PCHE activity increased to 1/4 to 1/2 that of plasma in CSF of patients with bleeding into CSF.

Inhibitory effect of quinidine on plasma pseudocholinesterase activity in pregnant women

The effect of quinidine at therapeutic and subtherapeutic concentrations on pseudocholinesterase activity in the plasma of 16 normal pregnant women was studied. The mean plasma pseudocholinesterase activity in the absence of quinidine (control) was 0.67 +/- 0.11 U/ml. The mean pseudocholinesterase activity in the presence of quinidine at concentrations of 0.5, 1.0, 2.0, and 5.0 micrograms/ml 0.48 +/- 0.09, 0.38 +/- 0.09, 0.29 +/- 0.10, and 0.19 +/- 0.09 U/ml, respectively. At therapeutic concentrations needed to treat cardiac arrhythmias (2 to 5 micrograms/ml), quinidine inhibited pseudocholinesterase activity by 60% to 70%. All the plasma samples had a normal dibucaine number (78 to 85). We recommend caution when succinylcholine and/or ester-type local anesthetics are used in pregnant women receiving quinidine.

Pulmonary toxicity of the insecticide fenitrothion in the rat following a single field exposure.

The pulmonary toxicity of the organophosphorus insecticide fenitrothion was evaluated following a single exposure of rats to the field formulation, at the site of an aerial spraying. Four groups of 40 Sprague-Dawley rats (including a control), set in wood enclosures, were placed under the aerial lines of the spraying aircraft. The degree of exposure was monitored at the ground level by air sampling and visual evidence of droplet activity deposition. Plasma pseudocholinesterase activity and pulmonary alveoli ultrastructure were used as indices to the fenitrothion exposure. Rat lungs were examined under light and electron microscopy at days 3, 7, 21, 60 and 180 after the exposure. Although a few signs of toxic lung injury were observed at days 3 and 7 there was no cholinergic crisis nor an effect on the pseudocholinesterase activity within 12 h in the exposed animals, when compared with controls. The alveolar toxic reaction was limited to small and discrete foci, and was entirely reversible within a period of 2 months. On a morphological basis it is thus concluded that a single field exposure to fenitrothion did not induce any permanent change in the alveolar area of the rat lung.

Plasma pseudocholinesterase: A potential marker for early detection of obesity

Plasma pseudocholinesterase activity, body weight and food intake showed significantly higher values in obese (ob/ob) mice than their lean littermates starting at the age of 35 days. The enzyme activity also showed a good positive correlation with age, body weight and food intake in all the mice from this age. Analysis of the data also indicated that between 35 and 58 days of age, pseudocholinesterase activity appeared to be more sensitive than body weight measurements in predicting obesity. Diabetic (db/db) mice on restricted diet, showed no significant difference in plasma pseudocholinesterase activity between the pre and post restricted blood samples. In contrast, diabetic mice on a non-restricted diet showed a significant increase in enzyme activity during the same interval of time. This suggests a relationship between hyperphagia, pseudocholinesterase and obesity.

Cholinesterase enzymes in the blood of patients with Alzheimer's disease

Plasma pseudocholinesterase activity was about 100% higher in patients with Alzheimer's-type dementia than in similar age controls. Red cell acetylcholinesterase activity tended to be lower in patients than controls. Administration of lecithin substantially increased plasma choline levels but did not alter activity of either of the cholinesterase enzymes.

Species variation in plasma cholinesterase activity

1. Plasma from 26 animal species has been examined for pseudocholinesterase activity, measured against butyrylcholine, and the electrophoretic mobility of an acylhydrolase. 2. There is similarity in activity between the species in each Order but considerable differences between some Orders. 3. Plasma pseudocholinesterase activity is unlikely to provide other than a very approximate guide to the susceptibility of species to paralysis by succinylcholine.

The effect of the ingestion of a hypolipotropic diet on the plasma pseudo-cholinesterase activity of spayed female rats.

It has been shown previously that the ingestion of a diet low in lipotropic factors induces a highly significant elevation in the plasma pseudo-cholinesterase activity of adult and weanling male rats (Hawkins and Nishikawara, 1951). This elevation is not observed when supplements of choline, betaine or methionine are added to the basal diet. The triethyl homologue of choline is not as efficient as these compounds either in lowering liver lipids or in preventing the rise in the pseudo-cholinesterase activity. In female rats, on the other hand, the ingestion of a hypolipotropic diet leads to a significant depression in the plasma pseudo-cholinesterase activity. The level of this enzyme in the plasma and liver of female rats is four to five that in the same tissues of male rats (Zeller and Birkhauser, 1941; Beveridge and Lucas, 1941; Mundell, 1944). The higher level of estrogen in the female rat has been shown by Sawyer and Everett (1946)

Some Effects of Protein Depletion and 2-Acetylaminofluorene on Activity of Rat Plasma Pseudocholinesterase

SummaryEvidence is presented for the identity Df the plasma pseudocholinesterase of dog and rat and that the latter enzyme is stable when stored at low temperatures. Protein starvation is accompanied by a decrease in rat plasma pseudocholinesterase activity. The activity of this enzyme has been shown to increase markedly in rats fed 2-acetylaminofluorene before any gross evidence od hepatoma can be detected. As the hepatoma develops and liver protein concentration declines, the pseudocholinesterase activity of the plasma decreases from this high level.