Cholinergic neurotransmission occurs in motor, autonomic and central nervous synapses and requires very rapid inactivation of its transmitter, acetylcholine (ACh). Acetylcholinesterase (AChE) rapidly hydrolyzes ACh to acetate and choline, thereby inactivating it. AChE is found in the neuromuscular junction anchored to the basal lamina which runs between the nerve terminal and muscle membrane. AChE is also found outside the nervous and neuromuscular system in blood, lymph, germ and liver cells suggesting a role for AChE not related to cholinergic transmission. Another less specific cholinesterase, butyrylcholinesterase (BChE), seems to contribute to the regulation of the ACh concentration in the synaptic cleft.