Influence of different ways of euthanasia on the activity of cholinesterases in the rat

We studied the influence of four methods of euthanasia (decapitation, exsanguination via cardiocentesis following ether anaesthesia, Nembutal anaesthesia, or immersion in a CO2 atmosphere) on the activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in the brain and in the blood of mature female rats. A significant decrease was observed in the activity of AChE in the whole blood in the group treated with Nembutal. There were no significant changes in the activity of BChE with any method of euthanasia. Euthanasia in a CO2 atmosphere was the best technique with respect to the results indicating lack of affect on the activity of AChE and BChE in the periphery and the brain, as well as from the point of view of the welfare of the animals.