MARIAN DIAMOND:
Mentioned previously,
antidiuretic hormone, ADH, will
act on the collecting ducts
to absorb water.
And if we have reduced ADH,
what disease do we develop?
Diabetes insipidus.
Diabetes insipidus.
And what does that mean then?
If this is antidiuretic, this
hormone we get rid of it,
then we have diureysis, which
is just excessive urination.
What does diabetes mean?
Diabetes means to pass through.
And with this kind
of diabetes, it's
water that's passing through.
So when you interrupt
this path in the rat,
the rat just sits by the
water fountain all day long.
Water's just passing through.
It has no antidiuretic hormone.
I put this in at this
time because you usually
talk about obesity and
diabetes, but there
are two kinds of diabetes--
one for water passing through
and diabetes mellitus.
So what's passing through here?
What does mellitus mean?
It means honey.
They didn't give it sugar,
they just knew it was sweet.
So this is sugar
passing through.
So you don't, after
having a class like this,
just say somebody has diabetes.
Is it diabetes mellitus or
is it diabetes insipidus?
All right, you can see
there's a big difference.
All right, with that now, let's
go to our collecting ducts.
We've got to get--
we formed urine,
this whole nephron
was secretory.
It was forming the urine.
It was our nephron.
Now we take the urine, we're
not going to be changing it.
It's just got to get
out of the kidney.
And so let's see
how it gets out.
So we, once again,
go back to our kidney
where we showed we had
a medulla and a cortex.
This was our medulla.
This was our cortex.
And we have all these collecting
ducts coming down now.
They've been up here collecting
from all these nephrons.
We'll just make a lot
of them coming in.
And they come down into a
pyramid shape down here.
So we speak about the
pyramids of the kidneys.
These are the
pyramids in medulla,
and it's just their arrangement
of collecting ducts.
But we want to find
out how they're
pouring the urine into the
next stage leaving the kidney.
So we'll have these
pyramids coming in.
And they'll be coming into
what are called calyces.
And these will be
receiving the pyramids.
And then we'll have
these coming together,
they'll eventually
come together.
So we'll have the minor calyces.
Calyx is singular for just this
one, and then we have major.
Just so you are
familiar with the term
where did they come from
when you study kidneys.
A major calyx would be
two coming together.
And then the major calyces
come together and will form--
clean this up a bit
here, excuse me--
they'll form the
pelvis of the kidney.
And then that's the
pelvis of the ureter.
This will be the
pelvis and our ureter
will be here as
we continue down,
but that gives us a
general idea of how this--
let's call this
pelvis of ureter,
or ureter, whichever you like.
And now you can see this
pelvis is down here,
so we're leaving the kidney.
We had put in pelvis
in previously.
So let's follow our ureter.
How big is your ureter?
How long?
The ureter, it's
about 10 to 12 inches.
And it's conveying, [? then, ?]
the urine from the kidneys
to the urinary bladder.
And it will have what's called
transitional epithelium.
This is one we haven't
encountered before.
Transitional
epithelium lines it.
Transitional epithelium.
What does that mean?
It means that it can
change its shape.
So if you have a lot
of urine coming down,
it gets thinner as
the ureter expands.
But when there's no
urine, it can contract.
And you see changes
in the epithelium,
so it can change shape--
--on flow of urine.
And then it will
have the-- the ureter
will have the smooth muscle
layers, two smooth muscle
layers.
Now what's interesting about
the production of urine down
the-- the transport of
urine down the ureter
is that it's not just
a continuous flow.
There are intermittent
contractions
every two to three minutes.
The walls contract
and pass urine along.
So it's not a continuous flow.
So it's not just
gravity working.
So you can still be passing
urine down your ureter
if you're standing
on your head because
of this controlled
constriction going down.
So now we want to bring
the urine into the bladder.
And how does it do that?
What part of the
bladder does it enter?
Let's look at a lateral
view of the lower abdominal
wall in the pill cavity.
So this is just a lateral view.
And we'll have the
kidney with its pelvis,
and its ureter coming down.
Ureter a retroperitoneal,
as is the kidney
we mentioned last time.
And we're coming in
now to the posterior
aspect of the urinary bladder.
I put this a little
too far away.
Let me pull it over.
This is a female bladder.
So this is the urinary bladder.
And we're entering in the
posterior inferior bladder.
And why is this
important to know?
You've heard of hysterectomies
when they remove the uterus.
Well, we'll see in a minute
that the uterus is back here.
Sometimes when they remove the
uterus, they nick the ureter.
So a constant flow of urine is
coming out from that female.
I was in the hospital
when the lady next to me
it happened to her.
So, you don't
forget those things.
All right.
Let's look now at anterior
view of the urinary bladder.
Again, we'll just
take the female.
And we'll see two little holes
here in this posterior wall.
These are for the
entrance of your ureter.
And this is your urethra to
take the urine to the exterior.
Clinicians will refer to
the trigone of the bladder.
What do they mean by trigone?
If we put a hypothetical
line a cross
between the ureters and
down to the urethra,
this area here is the trigone.
Now a question you might ask
when the bladder contracts
for you to urinate, what
prevents the urine from going
back up you're ureters?
There's a fold of
mucous membrane
over the opening of the
ureter to prevent or reflux.
Prevent reflux.
Now what can we say
about the bladder?
Well, it's a hollow organ.
It's lined, again, with
transitional epithelium,
because after your
urinate, it shrinks.
Epithelium has to be adaptable.
So it has transitional
epithelium.
And then lots of smooth muscle.
They call the smooth muscle
of the bladder the detrusor
muscle.
You'll see that term.
Detrusor muscle.
And the muscle will
have stretch receptors.
It's the stretch
receptor stimulation
that lets you know when
you need to urinate.
It has stretch receptors--
--that indicate time to urinate.
Also medically, they use the
term micturition for urination.
I don't know, but I
checked the books today
just to be sure that the new
books are still using it,
and they do.
So interchangeably,
urination or micturition.
So the texts say
that the bladder
has the capacity to hold up
to 700 or 800 cc's of urine.
Capacity to hold
700 to 800 cc's.
Just a little side point.
Many of the fellows
used to say they
didn't like to take
girls as transport--
transport them down to
Los Angeles from Berkeley,
because they had to stop
too many times for the girls
to urinate.
So they asked me,
whose bladder is
bigger, the male or the female?
And I'm still on
the search for that.
I called UCSF Department of
Urology, and they guessed.
But I can't find a book.
So if you find out
if females have
smaller bladders
than males, that's
why they urinate
more frequently,
or the fact that their pelvis
has an additional organ down
there, it has the uterus,
so the area is smaller.
Who knows.
But anyhow, if
anybody feels insulted
if somebody asks them
how many times they
have to stop going from
Berkeley Berkeley to LA,
you'll understand why
the question arises.
All right, let's see.
That gets us
through the bladder.
And now we want to
look at the urethra.
Urethra obviously
differs considerably
between males and females.
Urethral, as we said, goes
from bladder to exterior.
In the female, the urethra is
about 1 and 1/2 inches long.
In the male, it's between
7 and 8 inches long.
Let's take the female first.
Her whole urethra is
surrounded with smooth muscle.
Smooth muscle
surrounds whole So,
it's called the
internal sphincter.
Internal sphincter.
And it says, "it's under
control to prevent dripping
coming from the bladder."
Quote unquote textbook.
Whereas the external
sphincter is at the opening.
External sphincter.
And of course then, that's
going to be voluntary,
so it's skeletal muscle.
Now in contrast as
we look at the male,
let's take an anterior view.
We'll have the urinary
bladder and the urethra.
And we'll start with then
putting in structures
surrounding the urethra.
Let's begin with
the prostate gland.
We'll discuss this in
greater detail when we do
the male reproductive system.
Right now, we're just trying
to get urine out of the body,
so this is a prostate gland.
And then we have what's called
the Urogenital diaphragm.
Skeletal muscle.
Urogenital diaphragm.
So we'll stop for a
moment with those,
because we have then
between the prostate
and the bladder our
internal sphincter.
This represents our
internal sphincter.
And that of course
is smooth muscle,
and again, prevents dripping.
And the urogenital
diaphragm then
represents the
external sphincter.
You might expect the
external sphincter
to be down at the opening as
it is with the female urethra,
but his external sphincter is
here and that skeletal muscle.
So we divide the urethra
into three divisions.
Three divisions of urethra.
The first one will be
the prostatic division.
Prostatic division.
The second one will
be the membranous--
it's this part of the urethra
in our urogenital diaphragm,
so it's called
membranous division.
And the major part will
be the cavernous urethra.
Cavernous urethra
will be in the penis.
And we'll see that when
we develop the penis
with the male
reproductive system.
So we have roughly, the
prostatic is 1 inch long.
The membranous varies
with the literature-- some
say 1/2 an inch long to 1 inch.
And then that leaves
the cavernous up
to maybe 7 inches long, so
those are the various divisions
with--
let's be sure that I've given
you the majority of things
I wanted to give you here.
Oh, it's interesting
just to know
that the epithelium does vary
within the urethra of the male.
The epithelium of male urethra.
First part is going
to be transitional.
And then we're going to
have stratified columnar.
Some say it's pseudostratified,
so in case you read that.
Or.
And then we have
stratified squamous.
But the urethra in the male
will be used for both sperm.
We'll show how
the sperm come in,
but when the sperm
are coming in,
this will close so
that the urine does not
occur at the same time that
the semen is using the urethra.
All right.
Now with that, we begin
a whole new system--
our endocrine system.
What are some basic
characteristics
of our endocrine system?
We have in this system,
individual ductless glands.
Individual ductless glands.
And these glands are
rich in capillaries.
We need the blood supply,
because the endocrine glands,
they form and secrete hormones.
And these hormones have
specific target organs.
What do we mean by that?
We just had an example.
We had aldosterone
just to review.
And what was the target
organ for aldosterone?
STUDENT: Distal
convoluted tubule.
MARIAN DIAMOND: Distal
convoluted tubule.
So we learned not
only the glands,
but their target organs.
And each of these individual
organs has its unique cytology.
Cytology.
So now, what are our
endocrine glands?
These you know, it's just a
matter of putting them together
in a unit.
Names of endo glands.
One we've already studied--
the pineal gland.
Then we have the gonads,
the ovaries, and the testis,
the testes, plural.
What's the big one on the
anterior aspect of your neck?
Thyroid.
What's on the back
of the thyroid?
STUDENT: Parathyroid.
MARIAN DIAMOND: Parathyroid.
We had it with our osteoclats.
We have seven of them,
so what's the sixth?
We've studied it a little
bit, produces our aldosterone.
Adrenal cortex, adrenal gland.
We'll put adrenal.
And then what's the master
of the endocrine symphony.
The pituitary.
The conductor of the endocrine--
I should say, the pituitary.
So, let's look at these briefly.
The pineal.
We knew that was posterior
part of the epithalamus.
And it controls your
circadian rhythm.
Let's put regulates,
better word.
It regulates circadian
rhythm, produces melatonin.
Many people were
taking melatonin
to reduce jet lag until we
started letting them know
what else melatonin can do.
It can inhibit the gonads
in their development.
You know anybody
taking melatonin today?
Isn't it interesting
how it dropped out?
Everybody was so eager
till they found out
that this additional
concomitant here.
All right, that's basically what
we've learned about the pineal.
Of course, you can have a
whole course on the pineal.
The ovaries and
testis we're going
to cover when we study the
male and female reproductive
systems, but just briefly.
The ovary, will house
the ova, the eggs.
And they'll mature
in their maturation.
You notice I was very careful
to say that the ovary does not
develop the ova.
Where are the ova developed?
They are developed
in the yolk sac.
They migrate into the ovary
to mature and develop.
So ova originate in yoke sac.
The ovary does not produce them,
it allows them to mature there.
We produce two hormones here.
What are the two hormones
coming from the ovaries?
Estrogen and progesterone.
Produce estrogen
and progesterone.
Now in contrast, the testis
do produce the sperm.
They'll mature elsewhere.
We'll see when we develop it.
So the testes, plural,
do produce sperm.
The hormone coming
from the testes?
Testosterone.
Everybody anybody knows.
Steroid coming from the
testis as its name implies.
And then our next one
will be the thyroid.
We can say a little
more about thyroid,
because this is the only chance
we'll have to discuss it.
What does thyroid mean?
Shield.
We're familiar with
the thyroid cartilage.
So we would have a
shield of cartilage.
As we look at the larynx, this
would be the thyroid cartilage.
What cartilage was
immediately inferior?
STUDENT: Cricoid.
MARIAN DIAMOND:
Cricoid, good for you.
Cricoid cartilage.
And then we start our
rings of cartilage,
that are surrounding what?
Is it the trachea?
They're not complete
rings as you know,
so we'll put in a few of these
here with a purpose in mind,
so these are tracheal rings.
So now we can put in
our thyroid gland.
The thyroid gland is a bilobed--
meaning it has two lobes--
bilobed gland.
The lobes are connected
by an isthmus.
Connected by isthmus.
And the isthmus will cover,
thank you, the second
and fourth tracheal cartilages.
Isthmus of covers two
to four cartilages.
So we've got two here.
Here's one, two,
three four, five.
So we'll put in our isthmus
over two, down over four,
and then we'll have
the lobes out here.
So we can mark off our
gland in this fashion.
So now, as young anatomists,
when somebody says,
does the thyroid gland
cover the thyroid cartilage?
And what can you answer.
STUDENT: No.
MARIAN DIAMOND: No.
It's just independent down here.
Let's look at our
slides and then
we'll continue this next time.
Could I have first slide place?
This is a slide of the ureter.
And you can see this
epithelium, it's all collapsed.
This is what we
call transitional,
so it doesn't look like any
epithelium you've seen before.
But when the ureter is
full, this will stretch out.
But you can see the
other muscle layers
in the ureter, which will allow
for these spaced contractions
every two to three minutes.
And the next one?
Now this is transitional
epithelium in the bladder.
And the next one.
And this is a section through
the human urinary bladder.
Here's the epithelium here.
And you can see how
much smooth muscle
is in the wall that's going
to contract to expel urine,
going in many directions
with its stretch receptors.
And the next one.
And this now is
the male bladder.
And you could see
the orifice are
opening for that ureters,
the trigone, the urethra,
the prostate.
And the next one.
And now this is the back, so
this will bring in more things
than we see.
We'll get these when we study
the reproductive system.
We have the seminal
testicles, we
have the vas deferens
bringing in the sperm.
They'll meet here in
the prostatic urethra,
but here's the ureter coming
down with the seminal duct here
and the seminal vesicles
inferior to the ureter.
And the next one.
And now we get the
whole male urethra.
Up here, we had our internal
sphincter, the urinary bladder
here, the prostate here,
the prosthetic urethra,
the membranous urethra here
with the urogenital diaphragm
here giving us a short--
it's definitely shorter
than an inch, isn't it?
The new literature saying this--
we used to say always
a half inch here.
This is an inch.
And then we come down to
the cavernous urethra,
which we'll see
will be surrounded
by the cavernous
portions of the penis,
but that's roughly seven.
But internal sphincter,
external sphincter.
Next one.
And this is showing what?
What's it look like?
It's ciliated.
I'm going to skip it.
It looks like oviduct,
and doesn't belong.
Next one.
Now, as we look at the
male, a lateral view
of the male pelvis, here we have
our sigmoid colon coming down
our rectum coming
down to the anus
and the external anal
sphincter down here.
Here we have the
male urinary bladder
with prostate,
prostatic urethra,
the urogenital diaphragm, the
membranous urethra, and then
coming on out into
the cavernous urethra.
And the next one.
Now this one gets us up
to the pineal gland here,
posterior epithalamus.
Here's our thalamus.
Next one.
And this is the ovary where
we have the ova have arrived.
All the ova are going to
be there much before birth
and they'll be in different
stages of development
during your reproductive period.
You do not get new ova in
your ovary after birth.
And the next one.
And this is the lumen --
I'll be finished in a
second-- of the testis,
and these are the developmental
stages of the sperm.
These are called acrosomes
We'll learn about those
on the developing sperm.
And the next one.
And this shows the thyroid
gland here with its isthmus
and its lobes, trachea
beneath, thymus down here.
Next one.
I think that we'll talk
about the internal aspect
of the thyroid, but it's
a unique characteristic
of its cellular structure like
no other organ in the body.
So we'll learn that next time.
Enjoy your afternoon.
