The nervous cells trigger the
muscle are the motor
. The neurotransmitter of
motor neurons is . When a
motor is excited the
current flows along membrane of its
until reaching the at the
neuromuscular (the neural
impulse zone between the
extremity and the ). Near
the axonal the depolarization
allows entrance of calcium into
the axon ( that calcium also a
relevant role ). The calciumions
stimulate neuron to release
in the synapse.

then binds to
receptors in the surface of the
, the permeability of
membrane is altered an action
potentialis . The depolarization
is conduced along the
to the sarcoplasmic that thus
releases ions for the
contraction.