Cholinesterases belong to esterases and represent important animal enzymes with multiple biological function. Acetylcholinesterase (AChE) plays the key role in cholinergic neurotransmission, whereas the function of butyrylcholinesterase (BuChE) is still unrevealed. Both enzymes seem to act as neurogenic factors during the early embryogenesis and later on they may participate in some pathological alteration. In humans, these degenerative changes are related to the deposition of pathologic proteins in the brain and with the progress of the Alzheimer’s dementia (AD). Both AChE) and BuChE become recently the target for the most frequently used therapy of AD – cholinesterase inhibitors.

        Key words: acetylcholinesterase, butyrylcholinesterase, Alzheimer’s dementia