Hereditary neuropathies are diseases of the peripheral nerves that are genetically passed from parent to child. The most common of these is Charcot-Marie-Tooth disease type 1. It is characterized by weakness in the legs and, to a lesser degree, the arms -- symptoms that usually appear between mid-childhood and age 30.
1 Chlorine ions are colored yellow in the VRML model. 2  Sodium (Na +) and potassium (K +) are positive ions. 3  They are found on both sides of the membrane. 4  Na + ions are in greater concentration outside the neuron whereas K + ions are more concentrated inside the neuron. 5  Na + ions are colored pink in the VRML model.
When the action potential reaches the terminal, it activates voltage-dependent calcium channels, allowing calcium ions to flow into theterminal. In the resting state, neurotransmitters are stored in vesicles at the pre-synaptic terminal. Most neurons contain at least two types of synaptic vesicles, small (about 50 nm diameter) and large (70-200 nm diameter). Neurotransmitters are released in quantal units as each vesicle contains a given amount of transmitter.