Acetylcholine is a neurotransmitter in the brain and in skeletal muscles, where it causes muscle contraction. (however, acetylcholine inhibits cardiac muscle contraction.) the enzyme acetylcholinesterase, or ache, catalyzes the hydrolysis of acetylcholine and is necessary for normal muscle function. if acetylcholinesterase is inhibited, for example by nerve agents such as sarin, acetylcholine can build up in the synapse, causing paralysis and eventually death. draw the products of the hydrolysis of acetylcholine. include the appropriate hydrogen atoms at physiologic ph.