Page 185 - The Miracle of Hormones

Communication in Nerve Cells

In the picture on
the left you see a
patient with Par-
kinson's disease
working with her
doctor. In their at-
tempt to find a
cure for Parkin-
son's, scientists
continue to do re-
search on this
disease.

The Electrical Communication Between Neurons

At every moment, every nerve cell experiences a complex conver-
sion. Communication via neurons is an operation that occurs when elec-
tro-chemical or chemical messengers generate an electrical signal.
In order to understand electrical communication, we must first con-
sider another balance mechanism: the marvelous balance formed by the
electric charge in nerve cells, the ions. Ions perform an important func-

tion within neurons; there is one positively charged sodium and potassi-
um ion, two positively charged calcium ions and one negatively charged
chloride ion. In addition, there are some negatively charged protein mol-
ecules.
In its resting state, a neuron is negatively charged. In this state, neg-
atively charged proteins and various ions are within the nerve cell. Com-
pared to the number outside, there are more potassium ions and less
chloride and sodium ions inside the neuron. These are not arranged at
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random, and this proportion is specially determined and maintained.
The message left on the membrane receptors in the nerve cell initi-
ates a serial operation in the cell that is reminiscent of the domino effect.
In the course of this operation whose details are not yet fully known, it is

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