Red Cell Cholinesterase

General Information

There are normally 2 cholinesterase enzymes, one found predominantly in erythroocytes, lungs, spleen and nervous tissue (acetylcholinesterase). The other, found in plasma (cholinesterase or pseudocholinesterase), is synthesised mainly in the liver. Acetylcholinesterase is responsible for the prompt hydolysis of acetylcholine released at the nerve endings to mediate transmission of the neural impulse across the synapse. The degradation of acetylcholine is required for the depolarisation of the nerve so that it is repolarised in the next conduction event.

Acetylcholinesterase may be measured for the diagnosis and monitoring of poisoning with organophosphate or carbamate insecticides such as Parathion, Sarin and Tetraethyl Pyrophosphate. Reduced levels will be observed with poisoning, whether acute or chronic. Levels will return to normal as the affected erythrocyte population is replaced. This is the preferred test, but see also Cholinesterase - plasma, which can be substituted and may be valuable to detect repeated exposure.

Use the code CHOLIR  for RBC cholinesterase analysis for assessment of occupational exposure.