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Hi and welcome to Neurophysiology 101. It has occured to me that many of you have questions related
to autonomic dysfunction that require an understanding of normal neurophysiology. After all, how can
you understand
what's abnormal if you don't know what's normal? How can you understand
pathophysiology if you don't know physiology?
I am by no means infallible here. That is why I've chosen to place this in the advice column. I did work
for six years as an RN on a Neurology floor, and I do still remember some stuff despite having
autonomic dysfunction!
This is how I understand the system and I freely interject opinions! Also ,
spelling and grammer have never been
my best attributes.
OK, let's get started.
Some of this you already know, but let's review anyway.
PART 1: Basic anatomy of the nervous system, especially focusing on the sympathetic branch of the
autonomic nervous system.
The three general divisions of the nervous system are:
1. Central
nervous system (brain and spinal nerves)Your MOTOR pathways are in this system. They
carry impulses from the brain
to nerves supplying your muscles so you can move. Your SENSORY nerves
pathways are in this group too - they make
you feel things.
2. Peripheral nervous system (cranial nerves and spinal nerves)These are the CRANIAL nerves in
your
head. They control movement of your eyes, lips, mouth, nose, etc.
3. Autonomic nervous system (sympathetic
and parasympathetic systems)
Naturally, we will go into detail with #3. I just wanted to make sure you understand
that #3 has
NOTHING to do with the nerves that move your body or make you taste, smell, hear, etc.
Autonomic or "automatic" nervous system is an "involuntary" system that is supposed to keep a
constant state inside
the body despite changing external conditions.
It is made up of two parts: the sympathetic and the parasympathetic
nervous systems. (I think they
should have named it the "pathetic" nervous system because of what it does to us
when it
malfunctions, but nobody asked my opinion when it was named.)
Since the sympathetic system
is the cause of POTS and NMH, lets go there first.
First you have to remember basic spinal anatomy. The CERVICAL
vertebrae are in the neck, the
THORACIC vertebrae are behind the chest and abdomen , and the LUMBAR vertebrae are
just above
the tailbone. The SACRAL vertebrae or just SACRUM are the last.
The SYMPATHETIC nerve
fibers originate between the first thoracic and second lumbar vertebrae. Now
that's a long distance and sympathetic
nerve fibers come off each of the vertebrae from T1 (the first
thoracic vertebrae all the way down to L2)You're
talking about 14 vertebrae here, folks!
The sympatheitc nerve fibers, coming off the first four vertebrae, end
in all areas of the heart. Here is a
list of all the sympathetic nerves and what they innervate (what they supply):
There is a branch of the sympatetic nerve trunk that goes upward but does not come off the cervical
vertebrae. These nerves are called the "Superior cervical ganglion"
Superior cervical ganglion--------innervates
the glands in the eyes, the parotid gland in the brain, glands
in your mouth and neck
T1, T2, T3,T4
All four innervate the heart and lungs
T5, T6, T7, T8, T9
All 5 come together to form
part
of something called the CELIAC
GANGLION and from there innervate
the stomach and pancreas
T10
T11 ------------------------------ These three also form part of the
T12 celiac ganglion
and innervate parts of the stomach, pancreas,
adrenal glands (they sit above
each kidneys) and part
of the gut.
L1 ------------------------------ Meets up with some of the nerve fibers from T5-T12 to form the
Superior mesenteric ganglion that
innervates the first part of the
large intestine and the
small intestine.
L2 ------------------------------- Also meets up with some of the
nerve fibers
from T5-T12 to form the Inferior mesenteric ganglion
that innervates the colon, rectum
and bladder.
Remember how there was a branch up at the top that didn't come off any vertebrae?? Well, there is a
branch at the bottom that is right in front of the SACRUM, but doesn't originate from the sacrum. These
nerves innervate
the "reproductive organs".
Branches from all ganglia(nerve fibers) also serve blood vessels, sweat glands,
and hair follicles.
Bored with anatomy yet???? I am.
Lets move on to what happens when you stimulate
these babies!!!
You can stop here and allow a brain rest.
PART 2" Normal function of the sympathetic
nervous system.
With stimulation, these nerve endings give out a neurotransmitter (a fancy name for a chemical)
called
NOREPINEPHRINE. This causes the following to happen to the heart. (now remember this is NORMAL).
1. increased heart rate
2. increased conduction speed through the AV node (don't worry about it , it's just
an electrical node
that helps keep the old ticker ticking)
3. Increased contractility of the heart
(it beats harder not just faster)
4. Peripheral vasoconstriction (don't panic, I don't expect you to know what
that means; peripheral
means farther away from the central core of the body like the nerves in your hands and feet
would be
peripheral nerves. Peripheral blood vessels would be those in your hands and feet, arms and legs.
Vasoconstriction, I think you all know, means narrowing of blood vessels, making them smaller
inside.)So, it means
"making little blood vessels far away from the heart get narrow."
WHY THE HECK A BETA BLOCKER??????????????
Now bear with me on the next part. It's going to get a bit technical, but when we're done, you'll
understand
why so many doctors order beta blockers like Inderal, Tenormin, Toprol, etc. to treat us.
Sympathetic nerve
pathways as you saw before, innervate the adrenal glands ( remember - those little
glands above each kidney?)
When stimulated the adrenals release CATECHOLAMINES (norepinephrine and epinephrine) into the
blood stream. By the
way, epinephrine is the fancy medical term for adrenaline. They are the SAME
thing.
These 2 neurotransmitters
interact with Adrenergic receptors found in the cell membranes of the heart
and blood vessels. Don't worry about
the terminology here, just remeber that there are RECEPTORS
that soak up these chemicals in the heart and blood
vessels.
The RESPONSE of the heart and blood vessels depends on the type and location of the receptors
involved. There are 3 types of receptors.
OK, this is where it gets hairy. Stick with me, it will be worth
it in the end, I promise! This is where you
begin to appreciate what a physician has to learn and remember to become
a neurologist or a
cardiologist. (So I guess we should be more patient with them, but I can tell you right now,
I'm NOT!!!!
Guilty as charged!)
First I have to explain your blood vessel system: Think of a plumbing
project in your home. It's a closed
system of pipes with water in them. If you add more water, the water pressure
will go up. If you take
water out of the system, the water pressure will go down. If you replace all the pipes with
smaller
pipes and still have the same amount of water, the water pressure will go up. If you replace the pipes
with larger ones, the water pressure will go down. Ditto for your blood vessels and blood pressure. So
know you
understand basic blood pressure control. (Keep this in mind, you'll need it later)Well, you're
welcome to cheat
and scroll back up.
THE THREE TYPES OF RECEPTORS:
1. ALPHA - They are adrenergic (there's
that technical word again) receptors located in peripheral
arteries and veins. Remember what peripheral means? Farther
away from the core of the body? So they
are found in small blood vessels in the legs and arms. Right?
WHEN STIMULATED: they produce a very strong VASOCONSTICTIVE effect.(Shrink those little babies!)
Can you see how
stimulation of this system can cause high blood pressure??? Please say YES! You
know, smaller pipes, same amount
of water.... increased pressure.....
2. BETA 1 - Adrenergic(Oh, I'm sooo sick of this word) receptors that
are mostly in the heart.
WHEN STIMULATED: causes an increased heart rate (fast pulse), increase AV node conduction
(sound
familiar?), and increased force of heart contractions. This can cause increased blood pressure.
3. BETA 2 - Adrenergic (YUCK) receptors found in the walls of arteries and in the bronchial walls. (In the
lungs)
WHEN STIMULATED: cause smooth muscles to dilate (get bigger, open up) causing VASODILATION (get
bigger,
open up) of arteries and bronchi (You know, the smaller branches that look like tree branches
that are in the lung?)
You have smooth muscles in your bladder, gut, lungs...
Generally speaking: Epinephrine acts on ALPHA and BETA
2 receptors and norepinephrine acts on
ALPHA and BETA 1 receptors.
Now I know I promised this would
be all about NORMAL stuff, but this is the perfect place to add in a
little pathophysiology:
If you have
POTS, can you see that misfiring of these nerves can cause the BETA 1 receptors to receive
too much stimulation?
That would cause an increase in heart rate (hence the fast pulse you feel) an
increase in the force of the beat
(hence the palpitations you feel) and increased electrical activity that
keeps the heart hyperactive. Initially
this response causes a rise in blood pressure.
Now do you see why the doctors give you beta blockers. Please
say YES!!!
Those beta blockers, like Tenormin and Toprol,are "beta 1 selective adrenergic blocking agents." Now,
blocking the beta 1 receptor will cause a drop in your normal heart rate. Doctors hope that it will dull
that hyper
effect we get when the nerve misfires. I know that it has helped some people, but the
reason it doesn't work for
others is because, some people keep misfiring so badly, once the nerve is
stimulated that they just pump out tons
of chemicals. This is no match for the dose of beta blocker
you're on, Think of it as the nerve having a seizure.
Sometimes it's a mild seizure that only lasts a few
seconds and the medication can handle it. But for some its a
"grand mal" seizure that lasts for minutes
at a time.
Now some of you are thinking, ah why is this
used for treatment for high blood pressure? Well, because
stimulation of the beta 1 receptors causes high blood
pressure, and doctors want to dull this response,
but I can tell you right now that these medications only help
people who have mild to moderate high
blood pressure. They won't do too much for severe hypertension, they are just
not strong enough, and
often high blood pressure is a combination of factors that have gone wrong. Hence, some people
are
on beta blockers and water pills to control their high blood pressure.
I would encourage those
who have POTS to try the beta blockers to see if they help for you. (Well, you
might as well try, there isn't much
else out there, you know!)
So now I think we've answered the frequently asked question: Why the heck am I on
a blood pressure
pill?????
There is one more thing we have to discuss. Your body likes to stay in
balance. When it detects a too
rapid pulse, it will eventually try to drive your blood pressure down. Think of the
plumbing system. If
you increase the speed of the water flow, you don't need as much pressure to get it to where
it needs
to go, like making all the pipes slant down, so that gravity facilitates flow. Some people with POTS will
drop their pressure as their pulse races away, others have very little drops in pressure. Those who do
drop their
pressure, tend to faint more quickly. This is only in POTS. In NMH, the first thing that happens
is your pressure
drops, Why you ask? Scroll back up and read what happens when beta 2 receptors are
stimulated, because that's you!
You have smooth muscle receptors in your gut, lungs, etc... and it
causes those and the blood vessels to VASODILATE
(open up, get bigger) Soooooo... think of the
plumbing system again. You just replaced the pipes with bigger pipes
and you didn't increase the flow.
Drop in pressure, right? So blood pools in the gut vessels, the lung vessels,
the bladder vessels and
their isn't enough pressure to get that blood back up to the brain. Hence, your kissing
the floor again!
Doctors try to keep your blood pressure higher overall by asking you to increase fluids and salt.
Now
there is another malfunction involving the adrenal glands and the kidneys, that will also cause massive
losses of water and salt, which leads to decreased blood pressure. This is called the renin - angiotensin
- aldosterone
system and involves hormones controlled also by the sympathetic branch of the
autonomic nervous system. I don't
want to go there now because I have only run into one or two
people in the forum that have this type of autonomic
dysfunction and one of them is an RN It's also a
very complicated system to explain.
Well that takes
us to the end of this section of neurophysiology.
I would like to do more. The next topic would continue this
discussion and go over the parasympathetic
nervous system. Those of you with vaso-vagal syncope will find your problem
root cause in this system.
I would also like to go through baroreceptors and other things that influence our
symptoms, including
what the medical community thinks causes the muscle aches and the fatigue.
I
would like to discuss the role of serotonin and why certain antidepressants that increase serotonin
levels help
with the brain fog.
Lastly, I'd like to go over the current theory of why we get this. I'm no authority, and
there may be
more theories out there then I am aware of, but we good get a grip on the main ones.
However, this is a lot of data to convey. If you read this and find it too technical or not pertinent or
inaccurate,
please let me know.
If this isn't helpful, then there is no sense to keep going. I know that usually you have
to surf many
web sites to get one answer. When you find it, it is sometimes too technical to understand. I did this
because I have been getting the same questions asked over and over again, and instead of
responding individualy
it was easier for me to just post the info here in the forum for everyone.
Now, if there are errors, let me
now, but I won't stand corrected! (get it, STAND corrected, ha ha ha!)
Yuck, bad joke!
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Welcome to Neurophysiology 201.
I'm hoping you're here because you got something out of Neurophysiology
101!
Before we get started, I found a helpful website to illustrate what nerves are in the parasympathetic
and sympathetic systems and what they do. Now don't be insulted by the name of the website. I'm not
dumbing you
down, I just liked the pictures.
Go to: faculty.washington.edu/chudler/auto.html
Nice pictures,
simple explanations, right?
Okay, on with the show:
PARASYMPATHETIC NERVOUS SYSTEM
Remember it's the other branch of the autonomic or automatic nervous system.
I have seen in the most recent
literature, a reference to the third branch of the autonomic nervous
system called the "enteric" system. In my day,
that fell under the parasympathetic. If you'd like to pick it
out separately, go ahead. The entire enteric autonomic
system only innervates (supplies) the gut.
The parasympathetic nerves arise from something called the DORSAL
MOTOR NUCLEUS of the VAGUS
NERVE in the MEDULLA OBLONGATA.(What???) They start around the brain stem, you know the
bottom
of the brain before it becomes the spinal cord?
They are made up of the cranial nerves. There
are 10 cranial nerves involved in the parasympathetic
system. You may say, "I thought there were 12 cranial nerves!".
Well, there are, but the last two only
deal with motor movement that we can control. We're only interested in the
ones that can also cause
movements we can't control!
Now I'm not going to list all 10 cranial nerves,
because you can go to the website I just mentioned and
look at them. Besides, as soon as I mention them, you're
going to recognize them. Like, the first cranial
nerve is Olfactory -smell. Number two is Optic-vision, etc. The
parasympathetic cranial nerves deal a lot
with secretion. Lubricating tears in the eyes, nasal secretions from the
nose, secretion of acid in the
stomach, etc. Again, were talking about things we can't control.
WHEN
STIMULATED: The parasympathetic system releases a neurotransmitter (chemical) called
ACETYCHOLINE. Acetycholine
does the opposite of norepinephrine. (Which, as you learned in 101, is
produced by the sympathetic nervous system.)
PARASYMPATHETIC STIMULATION CAUSES:
1. a decrease in the rate of the SA node firing (just another
one of those electrical things that causes
your ticker to keep ticking)
2. a decrease in heart rate
3. the contractility of the heart is decreased (the force of the beat is decreased)
Notice how
1-3 are the opposite of what happens in the sympathetic nervous system!
Now cranial nerves #9 and #10 are the
biggies here! #9 is the GLOSSOPHARYNGEAL and #10 is the
VAGUS.
We'll focus mainly on the Vagus nerve
because it is HUGE and innervates (supplies) just about every
internal organ you can think of. Like the heart, lungs,
stomach, liver, intestines, bladder, etc.
The Glossopharyngeal innervates (supplies) something called the carotid
sinus. You know where your
carotid artery is? There is one on either side of your throat, and they are the ones
that supply lots of
blood to your brain. You can easily find your pulse (heartbeat) by placing two fingers on the
carotid
artery. It is not a deep artery, so it's easy to feel. Behind those arteries on either side, is a cavity
called
the carotid sinus. It has something in it called baroreceptors that we are going to talk about later.
Basically this carotid sinus monitors your blood pressure and pulse and sends out signals to the brain
like:
"1pm, and all is well"
"2pm, and all is well"
Unless it picks up a problem, like your blood pressure
has just gone up. Then it sends out a signal like:
"3pm, and all is not well; picking up an increase in pressure"
The vagus nerve is then stimulated by the medulla oblongata and heart rate and blood pressure go
down.
So that takes us to the good old vagus nerve.
Since it innervates (supplies) so many systems,
any little glitch can cause it to fire. Soooooo, you end
up dropping your heart rate and your blood pressure and
you're kissing the floor. YOU HAVE
VASO-VAGAL SYNCOPE! You are much more likely to faint with little warning. Most
people with POTS can
feel their heart rate increasing, and this gives them a little warning. It also keeps blood
flowing to the
brain. In vaso-vagal syncope, the poor brain is losing blood supply from both systems: the heart
rate
and the blood pressure. No increase in pulse, no increase in blood pressure, unless your sympathetic
nervous system realizes that you're in a jam!
Now to answer a specific question someone asked me. The vagus
nerve joins up with some of those
enteric fibers and supplies the gall bladder and bile ducts. If the vagus nerve
misfires in that area, you
are going to have gall bladder spasms and duct spasms. Sorry, sad but true!
So, some of you might be saying, "Well what about those of us who only get vaso-vagal syncope when
we turn our heads
too far to the left or right?". You people have either cut off the blood supply to the
carotid artery by turning
your head too far, or you've just inadvertently stimulated the baroreceptors
that live there. Or, you could have
done both!
Let's talk about baroreceptors now.
The changes that occur NORMALLY in the parasympathetic
and sympathetic nervous systems happen
because important receptors are located throughout the body and these receptors
send messages
around. (You know like:"1pm and all is well").
There are actually three groups of receptors.
(Hey, it's never that simple!)
1. Baroreceptors. (Long, long ago, we called these pressoreceptors) You already
know that some live in
the carotid sinus. (Remember, the little cavity behind your carotid artery in your neck?)
Well, the rest
live in the walls of the AORTA (the really big artery that carries blood away from your heart and
to your
body).
These baroreceptors get stimulated whenever they sense an increase in the blood presssue
of your
arteries. Then they send a message up to the brainstem, the vagus nerve gets called into action,and
the heart rate and blood pressure drop. Normally, just a wee bit. But watch out if they're
dysfunctional!!!!!! When
arterial pressure goes down enough, the baroreceptors send fewer messages
to the brain stem. Then sympathetic vasoconstriction(smaller
pipes) occurs and blood pressure and
heart rate go up again. Can you see how this is really a constant tug of war?
2. Stretch receptors. They are in the VENA CAVA ( the really big vein that goes to your heart) and in
parts of the right side of your heart. These receptors react to changes in blood pressure due to not
enough fluid
or too much fluid in the blood system. When your blood pressure decreases (because you
didn't drink any fluids today),
stretch receptors send a signal to the brain and the brain stimulates the
sympathetic system to compensate. Well,
I bet you can tell me in your sleep that the blood pressure
and heart rate will go up if the sympathetic system
gets stimulated! When your nurse forgets about
your IV and the whole bottle runs in over 15 min - you're waterlogged
and you're going to stimulate
these receptors. Then, it sends a signal to the brain to decrease heart rate and blood
pressure.
3. Chemoreceptors. Don't really need to talk about these. They go into action when you are exposed
to
things like too much carbon dioxide or when your blood gets too acidy (like in kidney failure).
Well, that about sums up the parasympathetic system.
I think the next topic will be about the theories. What
they think causes the glitches. I've received a lot
of e-mails about this one, so I think it should be next.
Again, all feedback is appreciated.
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NEURO-PATHOPYSIOLOGY 301
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CAUSATION THEORIES, otherwise known as, "WHAT THE
HECK HAPPENED TO ME THAT I'M NOW
AUTONOMICALLY DYSFUNCTIONAL?"
Well before I start on
this one, I need to apologize, in advance, to anyone who really does have
Attention Deficit Disorder. I'm
not making fun of you in this piece, I'm just trying to illustrate a point.
I also need to apologize
to all science fiction fans.
Lastly, I need to apologize for my warped sense of humor. It is a coping
mechanism I've developed after
having POTS for over 20 years, and vaso-vagal syncope for over 30 years. I
really need to be able to
laugh at myself and my disease. Also, if you don't like it, you don't have to read
it! Just skip over the
weird parts.
First, you have to understand where viruses go when
they are done beating up your body. They become
dormant along your nerve tracks. Really, I'm not kidding.
All viruses go there!
Just to convince you, I'll tell you about the chicken pox virus. Remember when
you or an older family
member had the chicken pox? And you've all heard of shingles, right? Well, shingles
is simply a
re-outbreak of the dormant chicken pox virus along the nerve tracks. Shingles are painful lesions
that
break out along the nerve tracks on only one side of your body. When the lesions break open and are
weeping, they contain live chicken pox virus! So, if you break out in shingles, it just means that you must
have had chicken pox sometime in your life, and something triggered a re-outbreak. Usually we see
shingles
in elderly folks whose immune systems are weak and can no longer keep the virus dormant. If
you have shingles,
stay away from people that have never had chicken pox and that haven't been
vaccinated for it.
Now lets talk about AUTO-IMMUNE THEORY. We already know that certain diseases are caused by our
own bodies
attacking us. For instance, in multiple sclerosis, the body attacks and destroys it's own
myelin sheath (the
covering around motor nerves). The body creates AUTO-IMMUNE antibodies
(self-killing antibodies) that attack
it's own tissue. Currently, as far as I know, the autoimmune antibody
theory is the main one for what causes
autonomic dysfunction. So , you may ask, "How the heck does
that happen?"
Well, you asked
for it.
Every time a virus enters our bodies, a group of antibodies are formed to try to kill off the
virus. So,
picture a whole class of antibodies being taught to recognize the intruder virus, attack it, and
kill it. But
some of these antibodies aren't the brightest, we'll call them "idiot antibodies". On top of
it , some of
these idiot antibodies have attention deficit disorder. The regular idiot antibodies and the
ADD ones,
make up only about 10% of all the antibodies in the classrooom. Some just can't learn the structure
of
the virus because they're either not bright enough, or they are too restless to listen carefully. The
instructor finishes the class by telling the antibodies that a chemical will come after them to call them
back, when they've finished their work. We'll call this guy, Officer O'Malley Antibaddy. Well, unfortunately,
the ADD idiot antibodies where too restless to stay until the end of the class. They left early and started
hunting down viruses. Soon the other healty antibodies and the rest of the idiot antibodies joined the
fight.
(Oh, the plot thickens!)
Go to the next post if you'd like to keep reading.
Some of the antibodies have already done a fine job of destroying a
virus cell and causing it to lie
dormant along an innocent nerve fiber. Along comes your worst nightmare:
an ADD idiot antibody. It
recognizes the virus and begins beating it. In the process, he's destroying the
nerve fiber the virus is
laying in. Other antibodies try to stop him, but he's really putting his heart and
soul into this. He has
now graduated to the title: Auto-immune ADD idiot antibody. If you're REALLY lucky,
Officer O'Malley
Antibaddy will come along at that moment and arrest the autoimmune ADD idiot antibody and
give him
30 years to life for abuse of a corpse. This will leave the poor nerve fiber damaged and inflammed,
but
not completely destroyed.
Well, if the nerve fiber, or the cells of the nerve fiber,
are not completely destroyed, it will take SEVERAL
MONTHS TO TWO YEARS for the nerve fiber to heal. Hence
we have those individuals who have a bad
case of autonomic dysfunction after an infection, but after 2 years
are doing significantly better.
What if Officer O'Malley Antibaddy isn't able to stop this auto-immune
ADD idiot antibody in time? The
nerve cells or fibers are completely destroyed. Nerve fibers such as these
do not spontaneously
regenerate.
Yes folks, I'm afraid they are dead, deceased, ceased to
exsist....,etc.
SONG IN MEMORIUM:
"Oh my darlin', Oh my darlin', Oh my darlin' nerve
o' mine"
"You are lost and gone forever, dreadful sorry, nerve o' mine"
You should sing
to your autonomic nervous system every day, I know I do! (Hey, it works for plants,
doesn't it?)
Second verse. Please sing along:
"Oh my darlin', Oh my darlin', Oh my darlin' brain o' mine"
"There's a minor, defect-finder, in yer post-ganglion"
(applause, applause, accolades...What....The Country
Music Awards????........Best New Neurology
Song.....)
Anyway, not all antibodies become
autoimmune antibodies because they're idiots. Some perfectly
healthy antibodies will attack nerve fibers even
if there isn't a dormant or active virus attached. Maybe it
happens something like this: A perfectly normal
antibody goes out of the classroom and begins
searching for the virus. He floats along until he comes to the
liver. He sees some of his buddies have
dropped into the Liverpool Pub for a few. He decides to join them
and help the liver do some
detoxification.
Once he's had his fill, or gets kicked out, he
continues on his way, hunting viruses. Coming upon an
innocent nerve fiber with no dormant virus, the antibody
says, "Hey, you look (hic..), you look(hic..), you
look jus' like this virussss I'm suppos' kill!" Although
the nerve fiber tries to convince the antibody that
he is not in fact a virus, the antibody doesn't listen.
He has now graduated to a full fledged auto-
immune-idiot antibody. If you're lucky, and Officer O'Malley
Antibaddy comes along, the auto-immune
idiot antibody will receive 30 years to life for assault with intent
to do bodily harm and for destruction of
a public transportation system. Again, the damage to the nerve could
be temporary if the nerve is just
inflammed, or permanent if the nerve has been destroyed.
In summary, we don't know why these antibodies attack the dormant virus in the nerve. We also don't
know why
some antibodies attack and destroy nerves that don't contain viruses. We only know that it
does happen. Testing
for autoimmune antibodies after having autonomic dysfunction for a long time, is
futile. The antibodies will
be long gone. You may never again make that antibody and you may never
damage any other nerve fibers. Some
of us will produce the antibodies again during a viral invasion, and
chances are high that they will cause
further damage to the autonomic nervous system. The abstract
that was on the forum a few weeks ago, (and forgive
me, I don't remember the title) was trying to prove
this theory. They had found that many people with POTS
and NMH have nerve damage in their legs.
Go to the next post to read on.
So, that takes us to the glitches. Once the end nerve fibers are damaged or destroyed, they will
over-react or under-react to a stimuli. Other nerves, that would never have been stimulated if the whole
system
remained intact, are sparked. The wrong message can travel up through the autonomic nervous
system and trigger
other wrong messages. We all know the results of that!
You might be feeling a little depressed right
now because it has dawned on you that there is no way to
cure this. The damage has been done. However, there
is hope on the horizon. Researchers are working
on ways to get nerves to regenerate. Specifically, they are
working with motor nerves that involve
voluntary movement. They are working to try to help people like actor
Christopher Reeves; people who
are quadriplegic. All motor neuron pathways are similar. If researchers do
make a breakthrough, it will
benefit all of us. Until then, we can only treat the symptoms and try to avoid
the triggers.
So let's get into some of those nasty symptoms and what causes them. Here is an example
of POTS and
NMH:
"Captain, I've detected an alien neurogenic field surrounding the ship!"
"Can we break free of it, Mr. Sulu?"
"We can try, sir."
"All available
power to the engines." "Whenever you're ready, Mr. Sulu."
"Aye, Captain!"
WHAP
"No effect sir, we can't break free."
"Red Alert! All hands to battle stations!" "Mr. Scott, I need more
power to the engines."
"Captain, I kinna do that! She's under a strain as it is!"
"Scotty,
I've got to have that extra power. Shut down all non-essential systems on decks 5 through 14
and reroute power
to the engines!"
"Captain,the engines will overload!"
"Scotty, the lives of 400 crewmen
are at stake, I need power now!"
"Aye Captain, rerouting power."
"Mr. Sulu. Bring us hard
about and try again."
"Yes sir!"
WHAP
"No effect sir." "We are still trapped
in the neurogenic field."
"Captain, the engines are at critical levels, I dunna think they'll stand another
run!"
"Sir, the neurogenic field, it's....gone, sir."
"What?, scan for the field."
"Scanners detect nothing in a 10 light-year radius, sir."
"Cancel red alert. Scotty, shut down engines, all
stop!"
"Mr. Spock, what do you make of this?"
"Curious, Captain. I believe the alien neurogenic
field was simply an illusion, that it never really
exsisted."
"Why would an alien being create
such a thing?"
"Most likely to protect themselves from intruders."
"So we were never really
in any danger?"
"Correct, Captain."
"Mr. Scott, damage report."
"Well,
the engines took quite a beatin', sir. The matter-antimatter waste system is backed up."
"How soon until
engines are at 100% efficency?"
"They'll be at 80% in two or three days, sir, but never at 100%. Not unless
we get to a starbase and
have her overhauled for two weeks!"
"Any other damage, Scotty?"
"Aye, decks 5 through 14 have blown several power grids, it'll take several days to replace them all!"
"Begin repairs immediately!"
"Aye, Captain."
Now pretend that the ship is stuck in a temporal
time loop, that repeats itself over and over again.
Just in case you missed the symbolism:
The alien neurogenic field is the stimulus that sets off the autonomic nervous sytem.
The Red Alert is the
reaction to the preceived threat your body sees because of the misfiring of nerves
along the autonomic system.
The shutting down of decks 5 through 14 is the way our body shuts down non-essential systems in
order to get enough blood to the heart and brain.
The matter-antimatter backed up waste system is (do I really
have to spell it out???) Well, it's
constipation.
The burnt out power grids symbolize fatigue.
The overloaded engines also symbolizes weakness and fatigue.
What REALLY causes the
fatigue, weakness, and joint pain?
Go to the next post if you want to read on.
OK, we were at "what realy causes the fatigue, weakness, and joint pain?"
Well, let's see. In
POTS, your heart rate is going around as though it just ran the Boston Marathon. In
NMH, your pressure can
go so low that hardly any blood is getting around. In vaso-vagal syncope, your
heart rate and blood pressure
are so low that blood is getting around very sluggishly.
Blood cells are supposed to give oxygen and nutrients
to tissue cells as they float by through the blood
stream. Tissue cells are supposed to give up all waste
products to the blood cell. The blood cell will carry
the waste products to the kidney and liver. Then the
blood cell will go pick up more oxygen at the lung.
Now, bear with me here.
If the
blood cells are going around too fast, they cannot stop long enough to give up all their oxygen
and nutrients
to the hungry cells. They also aren't around long enough to collect the waste products and
properly dispose
of them. We feel tired and weak because our muscle cells aren't getting the oxygen
and nutrients to keep going.
If the blood pressure and pulse are low, the blood is getting around so
sluggishly, it's not feeding the cells
fast enough, and it isn't getting there to remove waste products.
Also, pooling blood gets concentrated, and
loss of tissue oxygen causes build up of lactic acid (a waste
by-product). This builds up in muscle tissue
and causes cramps and muscle aches. It may take some time
before the body is able to clean up the mess. Less
oxygen and nutrients to the brain will cause the
"brain fog" we all love so much.
"Due to
recent autonomic activity beyond our control, oxygen levels will remain low for the next few
hours". "The
waste management team is backed up for several days. Please continue to leave all waste
products curbside
and they will be collected as soon as possible. We apologize for any inconvenience
this may have caused."
Well, at least that's how I understand the system!
ANOTHER THEORY:
You have all heard of the Chiari Malformation that infants are born with. They are born with a very small
opening in the skull where the brain and spinal cord meet. Parts of the brain are squished. The defect is
repaired as soon as possible in infants.
This theory suggests that people with autonomic dysfunction have
a smaller than normal opening at the
base of the skull, but not small enough to cause the obvious symptoms
that an infant presents with who
was born with a real bad defect. Some people may have been born with a slightly
smaller opening, and
some may have had it damaged in an accident.
The theory is that a small
piece of brain gets squished, enough to cause the autonomic nervous system
to misfire. Some people with autonomic
dysfunction have had MRIs that show a small opening that is
squishing part of the brain. Now, they can opt
to have surgery to open up the hole and unsquish the
brain. But let's take a closer look at that. For one
thing , it is MAJOR NEUROSURGERY! They have to cut
the back of your brain and spinal column open! And guess
what? What do you think has happened to
those nerve fibers that have been squished for the last 20, 30,40,or
50 years? Yah, well, they are
probably DEAD! Yes, they got destroyed from years of pressure on them. So, many
neurosurgeons won't
do the surgery because they know that you won't come out any better. That isn't to say
that, if you've
had a recent accident, the brain is squished and that's confirmed by MRI, and the nerves are
simply
inflammed, that this surgery wouldn't work for you; It probably would, but it would take almost two
years to know for sure if the surgery helped.
Many researchers believe that both theories are accurate.
That some people have autonomic
dysfunction because of an autoimmune antibody malfunction, and some have autonomic
dysfunction
because of damage where the brain meets the spinal column.
If any of you
know of other theories, please post!
Would like to address "managing symptoms" next time.
That ends this post!
Bye!
I found a website that describes autoimmune diseases and how they are caused. It's a bit technical
because
it gets into T cells and B cells, etc. You can browse through the whole thing or click on
"autoantibodies".
Remember, with autonomic dysfunction, this cause is just a theory. There could be a
glitch along any part
of the immune system. This website is good because it goes through all of the
known glitches that occur in
the immune system and gives specific examples of diseases.
You won't find autonomic dysfunction listed here
because it has not yet been proved that it is an
autoimmune disease.
Good luck!
Rita
www.niaid.nih.gov/publications/autoimmune/autoimmune.htm
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