MG Awareness Month: Vocabulary Lesson

It's June and that means it's Myasthenia Gravis Awareness Month. What is myasthenia gravis? Well, here's the description from Medscape: "Myasthenia gravis (MG) is a relatively rare autoimmune disorder in which antibodies form against acetylcholine nicotinic postsynaptic receptors at the neuromuscular junction of skeletal muscles."
 
If that made sense there is no need to read further. You won a video of a cat riding a Roomba.

On the other hand, if you read that sentence from Medscape and it sounded like, "Myasthenia gravis (MG) is a relatively rare sumthin-er-other-immune condition where thingamajigs form against doohickey dealiebopper thingamabob whatchamacallits at the humminahuh of whatchamawhoozit." Have no fear, I have a painless vocabulary lesson for you.

Our vocabulary words for today are: autoimmune, acetylcholine, nicotinic postsynaptic receptors, neuromuscular, and skeletal muscles.

1. Autoimmune
 Contrary to popular belief this does not have anything to do with vaccinating your car against muffler failure. An autoimmune condition is when the immune system goes haywire and mistakes regular normal parts of the body as dangerous and attacks them.

2. Acetylcholine
Acetylcholine is the main ingredient in nail polish remover. No, wait that's acetone. Sorry. Actually I am not really sure what acetylcholine is. Let me Google it.

Wikipedia says: "Acetylcholine (ACh, pron. ah-See-tul-KO-leen) is an organic, polyatomic cation that acts as a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms, including humans."

Well, that just cleared everything right up.

Let's try that again, using words that don't cost 25 bucks a piece. Ready? Acetylcholine is a substance that activates muscles.

3. Nicotinic Postsynaptic Receptors
 What is that, some kind of newfangled ashtray that disposes of nicotine after use?

Wikipedia says: "Nicotinic acetylcholine receptors, or nAChRs, are cholinergic receptors that form ligand-gated ion channels in the plasma membranes of certain neurons and on the postsynaptic side of the neuromuscular junction. As ionotropic receptors, nAChRs are directly linked to ion channels and do not use second messengers (as metabotropic receptors do). Nicotinic acetylcholine receptors are the best-studied of the ionotropic receptors."

There are actually people who understand words like these! I am not one of them. If you are not either, here's the simple version. Picture a game of catch. One person throws the ball, and the other person catches it.  The nervous system throws the acetylcholine ball. The muscles catch the acetylcholine with nicotinic acetylcholine receptor mitts. Once the acetylcholine ball is caught, muscles move.

4. Neuromuscular Junctions

Neuromuscular is a 25 dollar way of saying nerves and muscles. Neuromuscular junctions are where nerves and muscles meet up.

5. Skeletal Muscles

A skeletal muscle is any muscle you can move by thinking about it. Can you move your index finger, hold your breath, chew a cookie? You're using skeletal muscles.


Vocabulary Review
 1. Autoimmune

a.) A vaccine to prevent cars from breaking down
b.) When an unhealthy immune system mistakes part of the body as foreign and attacks it.

2. Acetylcholine

a.) An ingredient in nail polish remover.
b.) A substance that activates muscles

3. Nicotinic postsynaptic receptors

a.) A politically correct term for Newfangled Ashtrays.
b.) Receptors on muscle fibers that receive acetylcholine

4. Neuromuscular

a.) A therapist who specializes in treating sad and neurotic muscles
b.) Muscles and nerves

5. Skeletal muscles

a.) Skeletons don't have muscles. That's why they look so creepy. Duh!
b.) Muscles you can move by thinking about them.

Easiest test ever. Well done. You got a gold Star.

Now that we have learned some new words, let's take another look at that sentence from Medscape: "Myasthenia gravis (MG) is a relatively rare autoimmune disorder in which antibodies form against acetylcholine nicotinic postsynaptic receptors at the neuromuscular junction of skeletal muscles."

Remove all 25 dollar words...

Myasthenia Gravis, MG is a relatively rare disorder where the immune system mistakes critical parts of the human body as dangerous and attacks them. In MG the immune system attack is targeted at the junction where nerves and muscles meet. In all people, receptor sites on muscle fibers act like catcher's mitts. It is their job to "catch" acetylcholine, a substance that activates muscles. This how nerves tell muscles to move.

In MG, the receptor sites on muscles are destroyed by the immune system, stripping the receptors of their catcher's mitts. Without a way to catch acetylcholine effectively, the muscles are not able to move properly. The attack is focused only on muscles a person can move by thinking about them. The muscles of the heart and gut are spared. Without properly functioning skeletal muscles, people with MG experience rapid muscle fatigue.
 There, now you know more about MG. Congratulations! You just won a cat riding a Roomba.