Page 84 - The Miracle of Hormones

THE MIRACLE OF HORMONES

the amount of calcium in the blood. This will give you a better idea of the
importance of the wonderful work these cells do.
If the parathyroid cells conclude as a result of their measurement
that the amount of calcium has fallen too low, they immediately secrete
parathormone. At this stage, the cells demonstrate another conscious
activity: They "understand" that the level of calcium has fallen and take
appropriate action to restore the deficiency.
Put yourself in the place of the parathyroid cells and think: If you
were aware that the calcium level in the blood had decreased, what rem-
edy would you use to increase the level of calcium?
To answer this question you would have to be a scientist with every
means at your disposal to investigate the human body. If people had no
knowledge about calcium in the body, it would be necessary to do years
of research and receive assistance from the best biochemists in the world.
There would be only one purpose for this effort—to find sources of calci-
um that could be used in the body.
Finally, at the end of your research you would learn that there is a
great amount of calcium stored in the bones and that some calcium
leaves the body in the urine. You would learn that calcium comes into the
body from food through the intestines.
In the light of this, the three measures you could take to increase
blood calcium are:
1. Borrow some of calcium from the bones.
2. Find a way to recover the calcium excreted in the urine.
3. Arrange to have more calcium taken from the food.
But each one of these functions takes us into a different field of
expertise.
Before deciding on the first choice, you would have to persuade the
bone cells to lend you a portion of the calcium they have stored in the
bones. The bone cells (osteocytes) do not want to lose any of the calcium,
which is very important to the bones. However, you must find a chemical
formula that will allow the bone cell to release some of its stored calcium
into the blood. In order to find this formula, you will have to be aware of

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