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- [Voiceover] It's time to start moving

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into the actual glands
and going gland by gland

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through the body.

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We'll start with the hypothalamus.

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The hypothalamus is up in
the bottom part of the brain.

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It's really the homeostatic
control center of the brain.

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It helps to coordinate
the brain's activity,

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helps to process information
entering and exiting,

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helps to coordinate
all the hormone control

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of pituitary glands.

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So it's linking the nervous
system and endocrine system.

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It actually makes two of its own hormones.

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It makes antidiuretic
and it makes oxytocin.

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So by producing these two
hormones, it's playing the part

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of endocrine but it's also
playing the part of nervous

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because it's making these
hormones with nervous tissue.

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Now the hypothalamus is going
to control the secretions

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of the pituitary gland.

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Controlling because it
sends down stimulatory

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or inhibitory signals
to the pituitary gland.

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Ha ha, that pituitary gland.

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Lot of times you can hear it

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referred to as the master gland.

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Now, master gland, maybe, maybe not.

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Can think that the
hypothalamus controls it,

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but a lot of times you'll
think of it as master gland.

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Secretes eight different hormones

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that control other endocrine organs.

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And that's why it's a lot of times

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referred to as the master gland.

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It has a front and back,
anterior, front, posterior, back.

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So the anterior and posterior pituitary

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both make up the overall pituitary gland.

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The posterior pituitary is
connected to the hypothalamus

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and that means it can
receive the two hormones

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the hypothalamus produces.

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The hypothalamus produces
antidiuretic hormone

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and oxytocin.

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So it's produced in the hypothalamus

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and then transported to
the posterior pituitary.

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The posterior pituitary will store

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and then secrete those two hormones.

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So antidiuretic we already
said is being stored

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in the posterior pituitary,

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but it's meant to conserve water.

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Helps to balance the water in your bodies.

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The more antidiuretic hormone you have,

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the more water is being conserved.

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The more water is being kept in your body.

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Oxytocin.

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Oxytocin is going to interact

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with uterine contractions during labor.

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It deals with milk ejection

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as the infant is starting to feed.

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So oxytocin and antidiuretic hormone.

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Both produced by the hypothalamus,

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but stored and secreted through
the posterior pituitary.

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So here's a look at that
posterior pituitary.

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All of it is at the back
half of the pituitary gland.

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Now the posterior pituitary
could have a nursing infant,

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the stimulus is received,
travels up the spinal cord

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to the hypothalamus.

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It causes the cells in the hypothalamus

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to release more oxytocin.

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Oxytocin is transported
down to the mammary glands.

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So it's a feedback cycle.

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The stimulation of the nursing infant

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causes more milk production
and more milk ejection.

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But it's all helped by
the hormone oxytocin.

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Now to go to the front
side of the pituitary,

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go to the anterior pituitary.

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We still are controlled
by the hypothalamus.

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But in this case, the hypothalamus
is not producing hormones

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that are stored by the anterior pituitary.

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Instead, the hypothalamus
is producing, releasing,

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inhibiting hormones.

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So if our releasing hormone comes down,

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the anterior pituitary
releases that hormone.

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But if an inhibiting hormone comes down,

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the anterior pituitary will not

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release that particular hormone.

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So here we have ACTH, and
abbreviations are perfectly fine.

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ACTH stimulates the adrenal gland.

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Makes the stuff called cortisol.

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TSH, thyroid stimulating hormone.

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Well, thyroid stimulating,
it stimulates the thyroid.

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Causes the thyroid to be functional.

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FSH and LH, so
follicle-stimulating hormone

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and lutenizing hormone.

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Both will help stimulate
growth, development,

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and functionality of the gonads.

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So the ovaries and testes.

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But these two hormones
are typically not produced

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until puberty is reached.

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They happen to appear at the age of 10-13,

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well, that varies, sometimes
a little bit earlier,

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sometimes a bit later,
everyone goes through puberty

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at their own rate.

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But once an individual
is producing FSH and LH,

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they'll start to initiate
sexual maturation.

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It'll help with the development
and process of puberty.

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Prolactin helps with milk production.

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Growth hormone.

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Well, really, growth hormone does a lot.

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It makes things grow, which makes sense.

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So it has major effects on
the bones and the muscles.

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And most of its action is during childhood

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and early adolescence,

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when the largest amount of
growth is occurring in the body.

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Alright, we start with the hypothalamus.

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It can either give a releasing
or inhibiting hormone,

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goes down to the pituitary,

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and the pituitary can produce
these six major hormones.

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ACTH goes to the adrenal cortex,

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TSH goes to thyroid,

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FSH and LH head down to
the ovaries and testes,

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and yes, both males and
females have both FSH and LH.

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Prolactin, mammary glands.

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Growth hormones, mainly the skeletal,

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but muscles, and bones.

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So here are the basic
six hormones produced,

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stored, and secreted from
the anterior pituitary.


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Well, just like any other system,

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there are disorders, there's problems.

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We have the term hypersecretion
and hyposecretion.

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Well, hypersecretion is
when you have too much.

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Hyposecretion is when you have too little.

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In the case of diabetes insipidus,

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you have hyposecretion
of antidiuretic hormone.

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That means that there's not
enough antidiuretic hormone.

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Well, if there's not enough antidiuretic,

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that means the body's not
conserving water properly,

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which can lead to dehydration.

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So diabetes insipidus.

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Gigantism: hypersecretion of
growth hormone in children.

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That means there's too much
growth hormone in a child.

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They are growing faster
than the average child.

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Acromegaly.

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Acromegaly is still extra growth hormone,

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but it's extra growth hormone in adults.

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So that means really,
gigantism and acromegaly

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have the same problem:
too much growth hormone.

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Difference is, in
gigantism, the individual

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becomes very tall, but
everything's in proportion.

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Arms, legs, hands, feet,
everything looks normal, just big.

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While in acromegaly, now
things are not in proportion.

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The hands, the feet, the
face will be overgrown

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compared to the rest of the body.

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They get larger, more fit.

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Pituitary dwarfism.

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Well, we have hyposecretion,
so not enough, growth hormone.

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In this case, the individual
ends up with short stature.

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If a person's identified
to have pituitary dwarfism

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during childhood, they can be treated

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by actually being given
extra growth hormone.

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Extra growth hormone during childhood

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can potentially help to
increase the rate of growth.

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This is gonna show you the
idea of pituitary gigantism

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and pituitary dwarifsm.

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I'm willing to bet you
could probably guess

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which one is the gigantism
and which one is the dwarfism.

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Actually, that little guy
in the hand, dwarfism.

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The big guy holding him, gigantism.

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Here is acromegaly.

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These pictures are all
of the same individual

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throughout their life.

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The top left, young girl,
looks totally normal.

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Top right, you get a young female.

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You might say the face
is a little bit larger

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at this point, but not much yet.

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Bottom left.

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Look at how the forehead,
the nose, the jawline

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has increased in size.

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Bottom right, you can see
how the facial features

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are much larger and much coarser.

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The progression of acromegaly.

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The hypersecretion, or
too much growth hormone

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after typical growth has ended.