The Hormones Secreted
by the Pituitary Gland
Before going on to consider the names of the pituitary
hormones, it is worth repeating that the purpose of
this site is to examine those amazing things that happen
in the hormonal system that astound even the world of
science, and to consider more closely the creative art
of God. For this reason, it is better to concentrate
on how this system functions, rather than on the names
of the hormones. The complex Greek and Latin terms used
in medicine and biology are a deterrent for many people.
And sometimes these Greek and Latin terms just make
the operations of a very simple mechanism more difficult
to understand (or to prevent us from appreciating the
wonder that occurs in an amazing process). The majority
of experts in medicine or biology may not apprehend
the wonders that are before them owing to the magic
of these words. For example, they know in great detail
how the pituitary gland is structured and how it functions,
but they never think about the source of the intelligent
consciousness that this tiny piece of flesh demonstrates.
For this reason, we repeat that it is not necessary
to daunt readers unacquainted with medical literature
by devoting space to definitions of these terms. We
will only briefly mention the names of the hormones
and in the following pages we will examine the great
wonders of which they are the vehicles.
The pituitary gland is composed of two parts: the anterior
and the posterior glands. Each part secretes different
The Anterior Pituitary Gland
Commands come continually to all parts of the
body from the pituitary gland. By means of these
commands, a considerable number of the perfect
operations in the body occur.
The anterior pituitary gland secretes six different
hormones, whose functions have been determined. Some
of these hormones that act on other hormonal glands
are called "tropic hormones." They are designed to direct
the hormonal system. In the following pages we will
examine the functions of the tropic hormones together
with the structure and functions of the hormonal glands
that they affect. Another group of these hormones stimulate
the tissues of the body. The names of these hormones
are as follows:
Hormones which stimulate other endocrine (hormone)
glands (Tropic Hormones):
1. Thyroid-stimulating hormone (TSH)
2. Adrenal gland stimulating hormone
(adrenocorticotropic hormone - ACTH)
3. Follicle-stimulating hormone (FSH)
4. Luteinizing hormone (LH)
Hormones that act on body tissues (Non-tropic
5. Growth hormone (GH)
6. Prolactin hormone (PRL)
The Posterior Pituitary Gland
The posterior section of the pituitary gland is the
location where the hormones produced by the hypothalamus
are stored. Under the right circumstances, these hormones
are secreted by a command from the hypothalamus. These
1. Vasopressin (antidiuretic hormone)
The Miracle of Growth: The Growth
A one-year old baby is about twice as heavy and 50%
as long as on the day he was born. In one year, he gains
weight at an amazing rate. He also grows longer, and
his body grows in proportion. What causes a newly born
baby who weighs three kilograms and is 50 centimeters
long at birth to become a fully grown adult weighing
80 kilograms and measuring 1.80 meters twenty years
The answer to this question is hidden in the growth
hormone found in an amazing molecule secreted by the
In order for a baby to become an adult, he must grow.
The growing process happens in two different ways. Some
cells increase their bulk; other cells divide and multiply.
What directs and ensures these two processes is the
The growth hormone is secreted from the pituitary gland
and affects all of the cells of the body. Every cell
knows the meaning of the message sent to it from the
pituitary gland. In compliance with this message, it
grows or multiplies.
For example, the heart of a newly born baby is about
one-sixteenth the size of an adult heart, yet the total
number of cells in the baby's heart is the same as that
in the adult heart. As the body develops, the growth
hormone affects the heart cells individually. Every
cell develops according to the command given to it by
the growth hormone. As a result, the heart grows and
becomes an adult heart.
The growth hormone works like an expert sculptor.
Over a period of time, it turns a 50-cm. long
into fully grown adult of 180 cm.
The multiplication of the nerve cells
stops when the baby is six months old and still lives
inside the mother's womb. From this time until birth
and from birth to adulthood, the number of nerve cells
remains constant. The growth hormone commands the nerve
cells to increase in size. When the period of growth
of the nervous system has come to an end, it has reached
its final form.
In the picture at the bottom we see an adult heart.
While still in the embryonic stage, a baby's heart
develops under the supervision of the growth hormone.
In the picture at the top, we see the developing
heart that appears as a red nodule.
Other cells in the body (for example, muscle and bone
cells) divide and multiply throughout their period of
development. Again, it is the growth hormone that informs
the cells how much they must divide.
In the light of these circumstances we must ask this
How is it that the pituitary gland knows the correct
formula according to which the cells must divide and
grow? It is amazing that this piece of flesh, the size
of a chickpea, controls all the cells of the body and
causes them to grow by dividing or increasing their
bulk. Another question that must be asked is: who charged
this piece of flesh with this function? Why do these
cells throughout their lifetime send messages commanding
other cells to divide?
Here again we see the flawless excellence of God's
creation. Cells located in one small area ensure the
orderly division of trillions of other cells. However,
it is impossible for these cells to observe the human
body from outside to determine how much the body must
grow and at which stage it must stop growing. These
unconscious cells, in the darkness of the body, without
even knowing what they are doing, produce the growth
hormone (and cease producing it) when necessary. A perfect
system has been created that controls every stage of
growth and secretion of this hormone.
Obeying the growth hormone, our cells construct
our faces with perfect balance and symmetry. The
cells meticulously obey the command they receive
and grow in proportion to one another. Otherwise,
the symmetry in the human face would not be possible;
if the nose grew too large, the cheekbones may
not develop. Or, if the eye grew but the eye sockets
did not, the eye would not be able to perform
It is another wonder that the growth hormones command
some cells to increase in size and others to multiply
by cell division because the hormones that reach each
kind of cell are identical to each other. How the cell
that receives the command must react is written in its
genetic code. The growth hormone issues the command
to grow; how that growth will occur is recorded in the
cell. This shows the power and magnificence of creation
at every point in the development of the human body.
Yet another very important point is the fact that the
growth hormone affects most body cells. If some cells
obeyed the growth hormones and others did not, the result
would be a disaster. For example, if the heart cells
obeyed the commands of the growth hormone but the cells
in the rib cage refused to multiply and grow, what would
happen? The growing heart would be squeezed in the undersized
chest cavity and die.
The growth hormone ensures that all of the organs
in the body grow proportionately to one another.
For example, development of the organs in the
abdominal cavity and of the chest cavity is proportionate.
If the growth of the chest cavity stopped and
the heart continued to develop, the rib cage would
crush the heart and cause death.
Or if the bone of the nose grew but the skin on it
stopped growing, the bone of the nose would tear the
skin and become exposed. The harmonious growth of muscles,
bones, skin and other organs is ensured by the obedience
of each individual cell to the growth hormone.
The growth hormone also gives the command
for the development of cartilage at the ends of the
bones.1 This cartilage is like
the unformed shape of a newly born baby; if it does
not grow, the baby cannot grow. The cells in this area
cause the bone to grow lengthwise but how do they know
that the bone must grow in this way? If this bone grew
sideways, the leg would not lengthen; it could even
rip the skin and be exposed. But everything is planned
and this plan is written in the nucleus of every cell.
Another astonishing fact about the
growth hormone is when it is secreted and how much.
The growth hormones are secreted in exactly the right
amount and at the time when the period of growth is
most intense. This is very important because, if the
amount of hormone secreted were more or less than what
is needed, the result would be quite undesirable. If
too little hormone is secreted, dwarfism occurs, and
if too much is secreted, gigantism is the result.2
So, for this reason a very special
system for regulating the amount of this hormone secreted
in the body has been created. The amount of this hormone
secreted is determined by the hypothalamus, which is
recognized as the director of the pituitary gland. When
it is time for the growth hormone to be secreted, it
sends the "growth hormone-releasing hormone" (GHRH)
to the pituitary gland. And when too much growth hormone
has been released into the blood, the hypothalamus sends
a message (the somatostatin hormone) to the pituitary
gland and slows down the secretion of the growth hormone.3
Every bone cell in the body knows where it will
be, what shape it will have, and how large it
will grow. They obey without error the commands
they receive from the growth hormone. This communication
among its cells allows the body to grow in proportion.
Yet how do the cells that compose the hypothalamus
know how much growth hormone there should be in the
blood? How do they measure the amount of growth hormone
in the blood and made a decision based on this amount?
In order to explain just how great a wonder this is,
let us consider an example:
Let us imagine that we have used a special device and
reduced a person to several millionths of his original
size, that is, to the size of a human cell. We have
put him in a special capsule beside one of the cells
in the region of the hypothalamus.
The job of this person is to count the number of growth
hormone molecules in the capillaries passing in front
of him. He determines if there is a reduction or an
increase in the number of these molecules. It is well
known that there are thousands of different materials
contained in the blood. It is impossible for a human
being (if he is not an expert in the field) to know
from the molecular structure if something in front of
him is a growth hormone or something else. But the person
we placed in the hypothalamus must recognize with certainty
the growth hormones among millions of other molecules.
Moreover, he must check the amount of the hormone at
How can the unconscious hypothalamus accomplish this
task, which seems very difficult even for a human being?
How does it measure at every moment the amount of growth
hormone in the blood? How does it distinguish the growth
hormone from other molecules? These cells do not have
eyes to recognize molecules, or brains to evaluate a
situation. But they put into effect the commands given
to them in perfect a system that God has created.
If a little too much or too little growth hormone
is secreted, the results are dynamic. If too little
is secreted, dwarfism occurs; if too much, gigantism
is the result. For this reason, God has created
a special system to regulate the amount of growth
The growth hormone is not only secreted
in the developmental period but also continues in adulthood.
Under these circumstances you would expect that people
would continue to grow and become gigantic. But this
does not occur.4 When a person
reaches a particular size, his cells do not continue
to divide and grow. Scientists still do not know why
this happens. It is known that thanks to a very special
system, cells are programmed not to divide and grow
any more after a certain time. Given this situation,
a person should think about the Power that created this
perfect program. This shows us another wonder of God's
It is not very difficult to understand how important
it is that trillions of cells stop dividing and growing
together at the correct time. If some of these cells
did not stop dividing as others did, the result would
be terrible. For example, if the eye cells continued
to divide and multiply after the other cell groups have
ceased to do so, the eye would be squeezed in its socket
After speaking about trillions of cells suddenly stopping
their activities, there is something else worth remembering.
Cancer is a disease that we have been fighting for decades
and still have not conquered; it is caused by one single
cell continuing to divide out of control. This example
permits us to better understand the delicate balance
that exists in the body.
In adulthood, the growth hormone continues
to have an influence on a few special cells and stimulates
these cells to divide and multiply. This is another
wonder of creation that serves a special purpose. This
cell division no longer causes the body to grow, but
serves to repair and regenerate the body. For example,
skin cells and red blood cells continue to divide causing
our bodies to gain 200 million new cells every minute.5
These cells replace old and damaged cells. By this means,
the total number of cells remains constant.
The growth hormone has a special design by which it
brings several factors into use to ensure cell division
It is not possible for us to count the number
of growth hormone molecules in our body's capillary
vessels or to easily determine a rise or fall
in that number. But the cells that make up the
hypothalamus select the growth hormone from among
the thousands of different materials in the blood
and make the required adjustments.
For cell division and growth to occur, it is first necessary
that the cells increase in size, which is possible only
through an increase in their amount of protein. So,
the growth hormone has a special function in accelerating
the production of protein in the cell.
In the above photographs, we see a woman at 16,
33 and 52 years of age who has a condition caused
by excessive secretion of growth hormone during
adulthood. This condition is characterized by
disproportionate growth in the jaw, hands and
It is known that protein production occurs as the result
of a complex process. Scientists have been able to understand
only some of the superficial elements in this process
after long years of research. In order to produce one
molecule to accelerate the operation of this system,
it is necessary to know all aspects of it. The fact
that the growth hormone has a design that enables it
to speed up the production of protein is a proof that
the system that produces protein and the growth hormone
are created by God to act in harmony with each other
and perform their functions according to His command.
The growth hormone not only ensures the acceleration
of the synthesis of protein, but also ensures that the
requisite amount of raw material enters the cells for
this purpose. The main material needed for the synthesis
of protein is amino acids, the building blocks of protein.
As if they were aware of this information, the growth
hormone stimulates the cell membrane so that it can
receive more amino acids.
In order to speed up the synthesis of protein, the
metabolism of the cell must also be accelerated and,
to this end, the growth hormone cooperates with other
hormones. The thyroid hormone secreted during the period
of growth accelerates the metabolic activities of the
In the above picture of a growth hormone. It is
too small to be seen with the naked eye but it
acts within the body with a high level of consciousness,
intelligence and sense of responsibility. It is
a wonder how it is able to make a perfectly formed
human being. But the One Who actually creates
this wonder is God, the Lord of all the worlds.
In order for all this to happen, one more very important
thing is needed: energy. Even if all the systems we
have mentioned so far were perfect, they would be of
no use without a source of energy. Without energy, the
growth process could not occur. But the human body has
been so perfectly planned that this need too has been
provided for. In addition to all these intricate functions,
the growth hormone performs one more very important
duty. It ensures the release of fat molecules to mix
with the blood. In this way, each molecule will serve
as a source of fuel fulfilling the cell's energy needs.
When the growth hormone reaches the cell, it attaches
itself to the appropriate receptor on the membrane.
When the receptor is stimulated, the growth hormone
begins to perform its function.
When reading about the activities of the growth hormone
in the body, it is important to recall that what accomplishes
this is a lifeless, unconscious molecule formed by the
combination of a few atoms that have no hands, eyes,
or brain. It is remarkable that a lifeless bit of matter
can know when and where to go in the body, and when,
how and by what means to stimulate it. Unconscious atoms
cannot write messages and send them to one another,
but this wonderful event happens when some molecules
interact with each other. They immediately know what
they must do and then do it. For example, when some
molecules interact with the growth hormone, they immediately
begin to divide. Others decide to take more amino acids.
And for this it is only necessary to respond to the
growth hormone. How can such a conscious and organized
activity continue without interruption in the body?
To claim that all these wonderful balances came to
be in the course of time by the operation of chance
flies in the face of scientific fact and logic. This
is because only one deficiency could destroy the whole
system. In order for a living thing to survive, its
whole system and all its organs must come to be at the
same time. Everything reviewed so far about the growth
hormone and these delicate interrelated balances demonstrates
the fact that human beings were created perfectly as
a complete organism. Concerning the excellence of creation,
God says in the Qur'an:
He is God-the Creator, the Maker, the
Giver of Form. To Him belong the Most Beautiful Names.
Everything in the heavens and Earth glorifies Him. He
is the Almighty, the All-Wise. (Qur'an, 59: 24)
2 Arthur C. Guyton, John E. Hall,
Textbook of Medical Physiology, 10. Edition, W.B. Saunders,
3 Biological Science: A Molecular Approach, BSCS Blue
Version, 6. Edition, Colorado 1990, p. 521
4 The Incredible Machine, Washington D. C. National
Geographic Society, 1986, p. 226
5 The Incredible Machine, pp. 222, 225