Figure 16-18 Acetylcholine (ACh) release, diffusion across the synaptic cleft, binding to receptors on the end-plate membrane, and hydrolysis by acetylcholine esterase (AChE) in the absence of blocking drugs. (From Stiller R: Neuromuscular blocking agents. In Wingard L, Brody T, Larner J, et al [eds]: Human Pharmacology: Molecular to Clinical. St. Louis, Mosby-Year Book, 1991.)