Page 116 - The Miracle of Hormones

THE MIRACLE OF HORMONES

come narrow reaches the blood vessels by means of various hormones.
Cortisol arranges the response of the blood vessels to the constricting
and dilating factors that affect them, and thus performs another impor-
tant function in emergencies. 33
How does cortisol know the system according to which the muscles
around the blood vessels contract, and how can it organize the response
of these vessels to the contraction-dilation factors of the system?

It checks the movement of water:

Cortisol prevents fluid from entering cells when it is not required.
Thus, it helps to maintain the stability of the blood volume. How does a
cortisol molecule know that fluid has a tendency to enter the cells? And
how does it know the methods required to keep the fluid outside? More
importantly, how does it determine when fluid must be kept outside the
cells, not all the time, but just at those times when it is necessary?

In times of danger, to prevent a rise in body tempera-
ture, it inhibits the production of the relevant hormone:

Another wonderful effect of the cortisol hormone is seen in the case of
high fever. A rise in body temperature is a sign that the human body is
fighting an illness. This rise in temperature requires that a person rest and
sleep. The rise in temperature is not a side effect of the sickness; fever is a
specially adjusted security precaution to force a person who is fighting an
illness to rest. The rise in temperature is caused by the "temperature cen-
ter" in the brain, which is activated by a substance called IL-1 (interleukin).
Cortisol is also designed to deal with excessive body temperature.
When a person is in danger of death due to high body temperature, cor-
tisol lowers the temperature by inhibiting the production of IL-1, which
activates the temperature center. 34
How does cortisol know that IL-1 raises a person's body tempera-
ture and that high body temperature is dangerous for a human being?
How does it know where IL-1 is produced and how does it make a deci-
sion to inhibit its production?

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