Page 115 - The Miracle of Hormones

The Adrenal Glands

There are highly efficient refineries within tiny cells converting fat to sugar.

In emergencies it gives priority to the nourishment of the

brain and heart:

Cortisol molecules go into operation in emergencies and produce a
drop in the body's utilization of sugar. But here is another wonder; the ef-
fect of the emergency is not felt on vital organs such as the brain and the
heart. To give an analogy, just as in times of emergency, economic resour-
ces are deployed in particular areas of a nation, so the cortisol molecules
give a mobilization order and give priority to the nourishment of the
heart and the brain, curtailing the nourishment of other cells. 32
How do cortisol molecules know that some cells are more vital than
others?

It arranges the contraction and constriction of the blood

vessels:

Earlier we saw that blood vessels are not rigidly fixed pipes, but be-
cause the muscles around them can contract and relax, the diameter of
the vessels can be changed when the need arises. The command to be-

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