1.   These channels are normally closed, but the membrane around a particular sodium channel may become depolarised causing the channel to open.

2.   So we can express then the overall form of the action potential in terms of the differential activity, first of sodium channels and then of potassium ac channels.

3.   Evolution seems to have er devised a large number of specific inhibitors for sodium channels but not for potassium channels.

4.   Researchers decided to take a look at the gene that encodes the sodium channel in muscle.

5.   Woolf is particularly interested in certain abnormal sodium ion channels that are only expressed in sensory neurons that have been damaged.