What are chromaffin
wonder where that surge of energy comes from when you hear the
starting gun at the beginning of a race?
measure, it comes from the release of adrenaline into the blood
stream. The cells that release the adrenaline in response to the
gun blast are deep within your adrenal glands (you have two of
them located just above your kidneys). These adrenaline-containing
cells are called "chromaffin cells" because someone
found that they show up under the microscope when stained with
chromium salts. Much more is now known about "chromaffin
cells." For example, it is known that when these cells are
stimulated to release adrenaline, they also release enkephalins,
small opiate-like peptides, that some people say are responsible
for the euphoria that runners sometimes feel when they go jogging,
some so much that they bcome addicted to jogging.
us get back to the adrenaline that is released from the chromaffin
cells into your blood stream. Where does it go ? What does it
do? Well, for a start, adrenaline is a hormone and stimulates
cells in other organs and tissues far away from the adrenal gland.
It influences the muscle of your heart, increasing the force of
contraction so blood can be pumped to peripheral tissues (such
as leg muscles) more quickly and effectively, so you can start
your race as quickly as possible. Another site of action is the
liver, where it increases the rate of release of sugar from your
liver into the blood stream, as well as increasing the destruction
of toxic materials. Release of adrenaline from chromaffin cells
in the adrenal medulla can be increased up to 5-fold in response
to fear, pain, and physical exercise.
of what we know about chromaffin cell function comes from studies
in several laboratories over the last 10 years, using chromaffin
cells in cell culture. Large numbers of chromaffin cells (more
than a million) are present in the adrenal glands of cattle which
provide a ready source of experimental material at minimal cost.
Chromaffin cells are obtained by simply perfusing the adrenal
gland through its central blood vessel with a solution of collagenase,
which breaks down the material that holds the chromaffin cells
together in the intact adrenal medulla.