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Cholinesterase in the blood
Last reviewed: 05.07.2025
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Cholinesterase in the blood is one of many important and necessary enzymes, which for brevity in the medical world is called CE.
True, real cholinesterase is found mainly in the muscle tissues of the skeleton, in the tissues of the nervous system, a small amount of it is found in red blood cells - erythrocytes. Such cholinesterase is called acetylcholinesterase or AChE.
Another CE was called serum or pseudocholinesterase, but not because of its "falseness", but rather because of some secondary functions. Cholinesterase works mainly on the hydrolysis of acetylcholine, which in turn, as an important neurotransmitter, carries out the transmission of nerve impulses.
[ Why is cholinesterase determined in the blood?
The level and activity of CE helps to diagnose the degree of intoxication, clarify the condition and assess the functioning of the liver. Also, before serious surgical intervention, an analysis for CE is carried out to exclude all possible complications and risks.
In the serum, the level of such necessary cholinesterase is detected to assess the condition of the liver, to determine the degree of intoxication. Acetylcholinesterase is the first to react to any poisoning, a 40% drop in its level is considered a serious threat to health, when AChE is below 80% of the norm, nervous paralysis may occur, and its zero activity requires resuscitation. Cholinesterase is also important for assessing liver function. If cholinesterase reduces its activity by 40-50%, this is a signal of signs of acute hepatitis. A 70% decrease in the level of CE activity is evidence of the terminal stage of cirrhosis or an oncological process in the liver. Cholinesterase can be activated above the required level in various diseases, this is a sign of coronary heart disease (CHD), diabetes is also possible. Cholinesterase is also elevated in genetic hepatosis with hyperpigmentation - Gilbert's syndrome. It should be noted that cholinesterase in the blood can be absolutely normal in latent hepatitis, which occurs without obvious clinical symptoms. In such cases, a more thorough, detailed diagnosis is necessary.
Cholinesterase in the blood, its normal level and changes
Normal cholinesterase levels range from 5300 to 12900-13000 units/L.
A decrease in cholinesterase occurs with all chronic diseases associated with the liver, with developing cirrhosis, after surgical operations and the prescription of certain medications. Also, a sharp decrease in cholinesterase is possible with acute intoxication, oncological processes and myocardial infarction. In addition, many pregnant women have low cholinesterase in the blood, especially in the third trimester.
Increased cholinesterase signals hypertension, possible nephrosis, diabetes of all types, some mental illnesses (MDP), oncological processes in the mammary glands, acute alcohol addiction. In addition, in the first trimester, pregnant women may have increased cholinesterase, this is considered normal.
Cholinesterase in the blood is an important biochemical indicator directly related to other enzymes – transaminases. If cholinesterase is reduced, transaminase activity increases, and vice versa. If cholinesterase in the blood is normalized with the help of adequate therapeutic measures, this indicates that liver function has been restored.
What role does cholinesterase play in the blood?
In recent years, the functions of cholinesterase have become more clear thanks to multiple studies. In addition to the fact that this enzyme actively transmits nerve impulses, another property of CE was discovered more than twenty years ago – hydrolysis of excess acetylcholine. Thus, in Alzheimer's disease, with a decrease in activity and "depletion" of AChE, their function is taken over by pseudocholinesterase.
Serum enzyme can rightfully be called protective. Cholinesterase successfully protects the body from various toxins, especially carbamates, organophosphorus and others, which, unfortunately, are present in huge quantities in food today (pesticides, nitrates). Cholinesterase in the blood also copes well with poisoning with strong ether poisons - sarin and other similar ones, with an overdose of psychoactive substances. Cocaine intoxication can be neutralized with drugs containing synthetic CE. Regulation of the state of cell membranes, participation in the formation of peptides (molecular compounds of residual amino acids), choline metabolism - this is far from a complete list of functions that cholinesterase in the blood performs.
Where is cholinesterase produced?
Cholinesterase type II, that is, serum cholinesterase, is synthesized in the liver, partly produced by the pancreas, and cholinesterase enters the blood through its secretion by the liver.