(2) Voltage-dependent calcium gates open, allowing calcium to enter the axon terminal."End-plate acetylcholine receptor: structure, mechanism, pharmacology, and disease".
Research methods edit José del Castillo and Bernard Katz used ionophoresis to determine the location and density of nicotinic acetylcholine receptors (nAChRs) at the neuromuscular junction.This allowed the researchers to determine that the nicotinic receptors were localized to the motor endplate in high density.The 30 nanometer cleft between nerve ending and endplate contains a meshwork of acetylcholinesterase (AChE) at a density of 2,600 enzyme molecules/micrometer2, held in place by the structural proteins dystrophin and rapsyn.
"Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies".A b c Swash, Michael; Schwartz, Martin.
It functions very similarly to botunlinum neurotoxin (BoNT) by attaching and endocytosing into the presynaptic nerve terminal and interfering with snare protein complexes.Spinal muscular atrophies are disorders of lower motor neuron while amyotrophic lateral sclerosis is a mixed upper and lower motor neuron condition.Autoimmune disorders, in the case of neuromuscular diseases, tend to be humoral mediated, B cell mediated, and result in an antibody improperly created against a motor neuron or muscle fiber protein that interferes with synaptic transmission or signaling.
This usually starts with the observation of bulk, possible atrophy or loss of muscle tone.References edit Levitan, Irwin; Kaczmarek, Leonard (August 19, 2015).