Activity of cholinesterases in a young and healthy middle-European population: Relevance for toxicology, pharmacology and clinical praxis.

ABSTRACT

The activity of human cholinesterases, erythrocyte acetylcholinesterase (AChE; EC 3.1.1.7) and plasma butyrylcholinesterase (BChE; EC 3.1.1.8) represents an important marker when monitoring exposure to pesticides/nerve agents, and may also be used in occupational medicine in diagnosis and prognosis of some diseases. In this study "normal/baseline" AChE and BChE activity has been investigated in a young and healthy population, with subsequent evaluation of several intra-population factors including sex, age (categories 18-25, 26-35 and 36-45 years old) and smoker status. The modified Ellman's method was used for enzyme activity assessment in 387 young and healthy individuals (201 males and 186 females aged 18-45). A significant inter-sexual difference in AChE and BChE activity was found (AChE 351±67 for males and 377±65 for females, (µmol/min)/(µmol of hemoglobin), p<0.001; BChE 140±33 for males and 109±29 for females, µkat/l, p<0.001; mean±SD). Despite the finding that mean AChE activity somewhat decreased whereas BChE activity grew within the age categories of the tested subjects, no significant effect of age on cholinesterase activity was found (p>0.05). Smoking influenced cholinesterase activity - AChE activity in smokers was elevated (approx. 3% in males; 8% in females) relative to that in non-smokers (p<0.05). Smoking was found not to have any effect on BChE activity. Reference values based on confidence intervals for AChE and BChE activity were established. The presented results might be useful in routine clinical practice where the monitoring of blood AChE and plasma BChE activity is crucial for prognosis and diagnosis of organophosphate poisoning, in occupational medicine and in relevant mass casualty scenarios.