Butyrylthiocholine: A sulfur-containing analog of butyrylcholine which is hydrolyzed by butyrylcholinesterase to butyrate and thiocholine. It is used as a reagent in the determination of butyrylcholinesterase activity.Butyrylcholinesterase: An aspect of cholinesterase (EC 184.108.40.206).Thiocholine: A mercaptocholine used as a reagent for the determination of CHOLINESTERASES. It also serves as a highly selective nerve stain.Benzoylcholine: The benzoic acid ester of choline.Acetylthiocholine: An agent used as a substrate in assays for cholinesterases, especially to discriminate among enzyme types.CholinesterasesAcetylcholinesterase: An enzyme that catalyzes the hydrolysis of ACETYLCHOLINE to CHOLINE and acetate. In the CNS, this enzyme plays a role in the function of peripheral neuromuscular junctions. EC 220.127.116.11.Cholinesterase Inhibitors: Drugs that inhibit cholinesterases. The neurotransmitter ACETYLCHOLINE is rapidly hydrolyzed, and thereby inactivated, by cholinesterases. When cholinesterases are inhibited, the action of endogenously released acetylcholine at cholinergic synapses is potentiated. Cholinesterase inhibitors are widely used clinically for their potentiation of cholinergic inputs to the gastrointestinal tract and urinary bladder, the eye, and skeletal muscles; they are also used for their effects on the heart and the central nervous system.Kinetics: The rate dynamics in chemical or physical systems.