Chemical Synaptic Transmission at Peripheral Synapses
In the preceding chapter it was shown how transmission along a nerve fiber occurred by brief all-or-nothing impulses and that this impulse propagation depended on two main factors: first, the cable-like properties of the nerve fiber, the conducting core being ensheathed by a relatively resistant membrane; and second, the large and momentary increase in sodium conductance of this membrane when its resting potential was suddenly diminished. As a consequence, the extremely poor cable-like transmission along the nerve fiber is amplified at each segment in a self-regenerative manner. The all-or-nothing character of the propagation derives from the amplification that each segment of the nerve gives to the attenuated signal transmitted in the manner of a cable from the adjacent active region.
KeywordsSynaptic Vesicle Nerve Terminal Nerve Impulse Postsynaptic Membrane Neuromuscular Transmission
Unable to display preview. Download preview PDF.