الفهرس 
Pharmacology of vecuroniumOnly 14 pages are availabe for public view
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Abstract
The neuromuscular junction consists of a prejunctional motor nerve ending separated from a highly folded postjunctional membrane of the skeletal muscle by a synaptic cleft. Neuromuscular transmission is initiated by arrival of an impulse at the motor nerve terminal with an associated influx of calcium and a resultant release of the neurotransmitter, acefylcholine. Acetylcholine binds to nicotinic cholinergic receptors on postjunctional membranes, causing a change in membrane permeability to ions, principally potassium and sodium. These changes in permeability and movement of ions cause a decline in the transmembrane potential from about -90 mV to -45 mV (threshold potential) at which point a propagated action potential spreads over the surfaces of skeletal muscle fibers leading to muscular contraction. Acetylcholine is rapidly hydrolyzed (within 15 msec) by the enzyme acetylcholinesterase, (repolarization) and preventing sustained depolarization. Acetylcholinesterase is primarily located in the folds of the endplate region, placing it in close proximity to the site of action of acetylcholine.