MARIAN DIAMOND: We began with
the thyroid in the last lecture
and stopped just as we were
developing the follicles.
Said it was made
up of follicles.
And one way to
look at a follicle
is to think of a
bunch of grapes.
All those grapes would
be individual follicles.
But we're going to
cut through them.
So these represent follicles.
And we'll see that they're
lined with epithelium.
And so forth.
And some say this is
cuboidal epithelium.
But as we'll see,
its dimensions will
depend on the functional state.
Sometimes it will be higher.
Sometimes it will be flatter.
Now the follicles
are filled with what
is called a colloid, which
is a gelatinous substance.
So the green is colloid, the
jelly-like, we could say,
consistency.
And it contains the storage
form of the thyroid hormone.
The storage form of
the thyroid hormone.
What's that called?
Thyroglobulin.
Thyroglobulin.
The circulating form of the
thyroid hormone is called--
circulating form of thyroid
hormone equals what?
T3, Triiodothyronine.
Triiodothyronine.
Now, you can see we have
this iodine component
in the hormone.
So you need iodine in your
diet to form the hormone.
If you have low
iodine, the hormone
that is coming
from the pituitary,
from the anterior
pituitary hormone, which
is called TSH, thyroid
stimulating hormone,
acts on the follicles to
produce the thyroid hormone.
But if there's not
enough iodine to form,
the TSH keeps trying,
stimulating that follicle,
that group of follicles.
And what happens?
The thyroid enlarges.
And we form the condition--
what do we call the
very, very large thyroid?
A goiter.
You don't see goiters on people
who live close to the sea.
They get their products from
the sea and rich in iodine.
Where would you might see
those who don't get this?
The foothills of the Himalayas.
The women working in the
fields there have huge necks
with beautiful women.
But the public health didn't
even get in to get it there.
Maybe now, but when I was there,
they all had huge goiters.
So now if you have
an individual--
let's ask the question first.
What's the purpose
of a thyroid hormone?
What does it do?
It regulates the metabolic
rate of all tissues.
And it functions
in the development
of the nervous system.
You need the thyroid
hormone to develop
a healthy nervous system.
Helps develop the
nervous system.
So there are some people who
just don't have enough thyroid
hormone.
If you're a child and you don't
have enough thyroid hormone--
so hypothyroid as a child,
what do we call the condition?
A cretin.
Cretin.
Severe hypothyroid-- this
is severe hypothyroid.
Hypothyroid as adult, what
is the term that's used?
Myxedema.
Myxedema.
And what are the symptoms?
This would be then decreased
mental and physical activity.
Sometimes children even
using a derogatory term
for a playmate when
they're not too bright,
they just call them a cretin.
But you recognize
there's a reason because
of the reduced thyroid activity.
So let's see.
One other hormone that's coming
from the thyroid is calcitonin.
What does calcitonin do?
It lowers calcium,
blood calcium.
Lowers blood calcium.
So again, that basic
introduction to your thyroid
gland.
Let's move on to
our parathyroid.
Very important gland.
The parathormone,
you've studied.
Product.
What does it do?
It will raise calcium.
How does it raise calcium?
It acts on what cells?
Osteoplasts, right, which break
down the bone and liberate
calcium.
Parathormone is
essential to life.
Can get neuromuscular
problems severe
without the parathormone.
What's the location of
your parathyroid glands?
Well, para means near
thyroid, so we're
going to have-- remember
the isthmus of the thyroid
was over the second, the
fourth tracheal rings.
And then it was by a lobe.
This is our thyroid gland.
This was the isthmus.
Review, review, review.
And these little parathyroids,
there are four of them usually,
are on the posterior surface
of the thyroid gland.
That's why parathyroid.
So in green we've put in
four parathyroid glands.
It took a long time
for them to find those.
They would take out thyroids
for various reasons,
not knowing that
[INAUDIBLE] on the posterior
surface of thyroid were
these little glands.
All right, let's move
on to the next one.
Be the adrenal, what's it mean?
Ad, near, renal, kidney.
So we'll see-- whoops,
sorry, little big.
Have our kidney.
And on the superior
pole of the kidney,
just like a little hat up here,
will be the adrenal gland.
There are, of course, two
of them, one on each kidney.
And so they're on the
superior pole of the kidney.
Are they retroperitoneal,
or are they
within the peritoneal, cavity?
Is the kidney retroperitoneal?
So are the adrenal
retroperitoneal?
Sure.
Is the ureter retroperitoneal?
Sure.
All right.
So it's retroperitoneal.
Clinically, you'll get
stressed with this.
Peritoneal may seem
minor now, but it's not.
Now the adrenal
has two components.
It has an adrenal medulla
and adrenal cortex.
Medulla would be inside then,
so this is my adrenal medulla.
And most of the
adrenal is the cortex.
So if we look at the
adrenal medulla first,
it's of neural origin.
Quick review.
Remember our nervous
system was forming
from a sheet of ectoderm.
And then it folded,
forming our neural groove.
And up on these neural folds we
had neural crest cells forming.
Neural crest.
So as the differentiation
continues,
the neural curve drops
down, forms our neural tube,
and our neural crest
cells are found here
between surface ectoderm
and our old tube.
What does a neural tube form?
The what?
And what else?
Your whole brain.
Your whole CNS.
CNS.
And these neural crest
cells migrate out.
Some of them will form
DRGs, but others will
form adrenal medulla cells.
So the adrenal medulla is
coming from neural crest cells.
Now these cells,
these cells which
form the adrenal medulla
will allow the cells then
to form hormones in a category
called caticholamines.
So adrenal medulla
forms caticholamines.
And these will
include two hormones.
Let's give epinephrine.
Epinephrine acts like the
sympathetic nervous system.
Sympathetic nervous system.
So example, is it going to speed
the heart or slow the heart?
Speed the heart, sure.
And the other caticholamine
norepi or norepinephrine.
And it is, for example,
a vasoconstrictor,
constricts the blood
vessels, vasoconstrictor.
Now the majority of the adrenal
will be the adrenal cortex.
And it will have two main
classifications of hormones.
It will have the
glucocorticoids,
and the mineralocorticoids
Glucocorticoids
and mineralocorticoids.
What are our glucocorticoids?
Cortisol and hydrocortisone.
What are they doing for you?
I can hear some noises, but
I can't hear specifically.
They are released
during stress, right?
They affect every
cell in the body.
So when you have
excess glucocorticoids,
they can reduce immune function.
Reduce immune function.
But they also reduce cerebral
cortical structure in excess.
Another reason why you've got
to learn to monitor your stress.
What disease do they
take cortisol for today?
I hear a lot when
my students come in.
You heard of lupus?
When the immune system
is attacking the body,
you want to cut down that
immune system activity.
You take cortisol.
But then, again, you see what
it's doing to cerebral cortex.
Always choices.
We took out the
adrenals of rats,
and the cerebral cortex
grew tremendously.
We don't recommend
it, but it shows
that the cortisols are
keeping a dampening on it,
especially when stressed.
So we try not to
get into stress.
And look around at final
time, do we succeed or not?
We try to help.
Mineralocorticoids.
What are they?
Mineralocorticoids will
be adjusting, regulating
water and electrolytes.
So number two is regulating
and electrolytes.
What's the example of
a mineralocorticoid
that we've given you already?
Aldosterone, good for you.
Example aldosterone.
Where does aldosterone act?
Distal convoluted tubule, right.
And what's it doing then?
Increasing water and sodium.
Right, electrolyte.
Increases water
and electrolytes.
And in this case,
it will be sodium.
All right, so your adrenal
cortex and adrenal medulla
have very different functions,
but they're put together
into one single gland.
What diseases are there
of the adrenal cortex?
Addison's disease and
Cushing's disease.
Addison's disease, which
will be hypofunction
adrenal cortex,
low blood pressure,
frequently pigmented
skin, and other symptoms.
Just so you're
familiar with the terms
that are related
to abnormalities
of the adrenal cortex.
Cushing's disease.
How many have heard
of Harvey Cushing?
Anybody?
Different era.
He was a great neurosurgeon.
Everybody in medicine had
heard of him 50 years ago.
Cushing's disease
is hyperfunction
of a adrenal cortex.
The simple function will
be high blood pressure.
High blood pressure
plus obesity.
So when you learn your
endocrine glandular
normal function and then
abnormal function either hyper.
Now we go on to the
anterior pituitary.
how many have had the
endocrinology course here?
Not many.
I was just thinking
endocrinology
is the whole
semester and here we
try to get this across to
you in an hour and a half.
So let's look at
the pituitary gland.
What bone surrounds
the pituitary gland?
Sphenoid.
What do we call a specific area?
Sella turcica.
Good.
All right, so we
know its location.
Turkish saddle.
Now it has two components.
we have a neurohypothesis.
And we have an adenohypothesis.
The a neurohypothesis.
Is the posterior pituitary,
and the adenohypothesis
is the anterior pituitary.
What does hypothesis mean?
First thing they learned
about the pituitary
if they took it out,
animals stop growing.
It means "to grow."
In fact, the first work
was done in Argentina.
They took that out, But they
encroached on the hypothalamus.
You have your ventral medial
nucleus of the hypothalamus.
When you injure that,
you get a fat rat.
So they said, the effect
of taking out the pituitary
is obesity.
Then they realized the mistake.
So you watch over history
the refining of technology
to find out the true
function of an area.
So neurohypothesis,
posterior pituitary,
obviously has neural origin.
It's coming from the
floor of the diencephalon.
The adenohypothesis is coming
from what's called a stomodeum,
but we're just got a call
it the roof of the mouth
in the embryo.
So very different origin.
This is a roof of mouth.
What do we know about
our neurohypothesis?
The posterior pituitary.
Hormones.
We have two.
One we've talked about
it just recently,
anti-diueretic hormone.
Where's the anti-diueretic
hormone acting?
Collecting duct.
Good for you.
What do we call a
condition when we don't
have anti-diueretic hormone?
Water's passing through?
What did we say it was?
Diabetes insidious.
Good for you.
All right, then
the other hormone
coming from the posterior
pituitary, what's it called?
Oxytocin?
Where does oxytocin act?
In the female,
during birth oxytocin
acts on the uterus to induce
contractions for birthing.
How many of you have
watched a birth?
A few.
Did you find that
the most thrilling
experience in your life so far?
Probably.
Yes.
All right, in the male, why
does the male need oxytocin?
Oxytocin acts on
his vas deferens.
We'll study the male
reproductive system
like we'll study
the females soon,
but I'm just going to put
it in here to complete.
Acts on the smooth muscle
of the vas deferens.
So it gives strong contractions
during ejaculation.
Sperm.
Ejaculation.
All right, where are these
two hormones produced?
Are they produced in
the posterior pituitary?
No.
Where are they produced?
They are produced
in the hypothalamus.
They're just stored
in the pituitary.
Produced in hypothalamus,
stored in pituitary.
All right then, let's look
at the anterior pituitary.
We will look at
five hormones here.
Just a word about each.
And they are given names
with regard to the hormone
that they're dealing with.
So the first one will
be the and of And 50%
of the cells in the
anterior pituitary
deal with somatotrophs,
of somatotrophs,
growth hormone making the
news a great deal lately.
People have discovered it.
and you take growth hormone?
Interesting to ask
these questions.
Why or why not?
Then we have corticotrophs.
They make up about
20% of the cells.
This is percent of cells
in anterior pituitary.
Now the corticotroph
that's most used is ACTH.
Have you heard of ACTH?
ACTH, coming from the
anterior pituitary.
ACTH stands for
adrenocorticotrophic hormone.
adrenocorticotrophic hormone.
So where does ACTH act?
So what's one hormone
that it would liberate?
Cortisol?
Aldosterone?
We just listed them.
Then we gonadatrophs.
And they account for about 5%.
What would these
gonadatroph hormones be?
Follicle stimulating hormone
and luteinizing hormone follicle
stimulating hormone, FSH,
and luteinizing hormone.
FSH equals follical
stimulating hormone.
So what it's going.
To be acting on, the
follicles of the ovary, sure.
What hormone will be released?
Estrogen. Somebody has had this.
It's not the follicle
itself, as we'll
see when we study the
female reproductive system
but it's a tissue on the
outside of the follicle.
Then the LH is
luteinizing hormone.
So from its name, one
what's it acting on?
Corpus luteum.
Corpus luteum.
And what hormone does the
corpus luteum produce?
Progesterone.
But this is all in the female.
What is follicle stimulating
hormone doing for the male?
I want to take this off and
I'll continue with my other two.
Sorry.
So FSH in male will be
acting on the tubules that
produce the sperm, the
seminiferous tubules.
We'll just put
tubules right now.
Tubules in testis, because
we'll have this when
we study male reproduction.
Acts on tubules in
testis to produce sperm.
What is luteinizing
hormone doing in the male?
The testis has cells
called interstitial cells.
It's acting on interstitial
cells in testis.
We'll see this
with the male when
we do the reproductive system.
And what did those
interstitial cells produce?
testosterone.
All right, so much
for our gonadatrophs.
We have two more.
Thyrotrophs.
Gross now who can put two
and two together and tell me
what the thyrotroph is?
Thyroid stimulating
hormone, sure.
We just had it, TSH Thyroid
stimulating hormone.
And thyroid stimulating hormone
is going to be producing what?
T3 setps-wise, and that's
for metabolic rate.
And nervous system development.
And that takes us now,
what's the fifth one?
Mammotroph.
Mammotroph.
The mammotroph
will be prolactin.
Prolactin.
Carl Nickle, professor
here, worked on prolactin.
It's the biogenic hormone.
Everything is
influenced by prolactin.
It's amazing how much
action it has on our bodies,
but primarily it acts on the
mammary glands to secrete milk.
Do you have time to enjoy
playing with things, memories
when they slide in when you're
trying to do something else?
I remember when we
first went to Harvard
we were playing a word game, and
they were acting out things--
what do they call it, charades?
And they were trying to get
the key thing was tit for tat,
and I was such a
biologist, just full of all
of this coming from Berkeley,
and I said, mammary gland,
and it just brought
down the house.
That was so strange to
call a tit a mammary gland.
But anyhow, that's what
slid into my memory.
I just have to share
with you the fun
of having this brain
that has, for all
those years, that little
bit of information
that I never shared
with anybody.
But anyhow let's
look at some slides.
Oh, I should have put
mammary glands work 20%
and thyrotrophs were 5%.
That'll give you your 100%
Somatotrophs were 50%.
Corticotrophs were 20%.
Gonadotrophs 5%.
Thyrotrophs 5% Mammotrophs 20%.
But it gives you an idea of
the proportion of function
of these hormones coming from
that little anterior, which
is no bigger than
the size of a pea.
And half of it is
going to human growth
hormone for your skeleton
and your muscles.
And the whole
gonadotrophs are only 5%
for their very important
function for reproduction.
Sort of an interesting
proportion there.
We only have a few
slides with this section.
Coming back.
I think we are
losing our batteries.
You see that little
tiny green dot?
Not very well.
Do we have another pointer?
At the bottom of the DVD player.
I see it, OK.
I'll put this one out so
you'll pick it up so--
I'll put it here.
Thank you.
There we go.
So our thyroid that we
mentioned with the isthmus
and bi-lobed, filled with
follicles loaded with colloid.
And the colloid holds
the storage form
of a thyroid hormone in it
in the form of thyroglobulin,
liberates it out into
the vascular system
to act on cells
all over the body,
to regulate their
metabolic rate.
And it's called T3
or triiodothyronine.
On the posterior
surface of the thyroid
we have the parathyroids.
Four of them.
Essential to life to
regulate your calcium.
Don't underestimate the
role of calcium in the body.
Then we had the adrenal.
Can we have the next one?
I think I have a few more
of the thyroid just to show.
Oh, this is the parathyroid
acting on an osteoplast.
That's a big one.
It's dissolving the bone
to liberate the calcium.
In the next one, what are these?
Colloid follicular cells.
They are acted upon by the TSH
from the anterior pituitary
to form the storage
form, the thyroglobulin.
When it's liberated out into
the bloodstream then it's Te.
The next slide,
very active thyroid.
Can't call these
colloidal cells.
In the next one, what
do you think this is?
Adrenal, did you say?
You think it's adrenal?
Why do you think it's adrenal?
what's the adrenal look like?
does it have a
medulla and a cortex?
Yes.
This is the adrenal.
You can see that the majority
of it will be cortex.
Next slide, and then this
will show the pituitary.
Different names have been
given over the period of time.
The pars systolic, the anterior
lobe or the adrenal hypothesis,
adenohypothesis.
Pars nervosa is posterior lobe
because it's of neural origin,
coming from the floor
of the diencephali.
The anterior lobe has migrated
up from the roof of the mouth.
Some say the nasal
pharynx, but it's
the general region of
the most superior part
of your digestive system.
And then you can
see how rich it is
in veins and arteries carrying
hormones from the hypothalamus
down to act on the anterior
pituitary and posterior
pituitary.
Next one.
Is that all?
All right, that's it.
If Eva is here.
