Nerve Excitement
Janelle Klein MSN, ARNP
I remember sitting in my Anatomy and Physiology class as Mrs. Applegate methodically drew a nerve cell on the board. Her cheerfully shrill voice added important details which I, along with over 200 students, frantically attempted to capture in our notes. She started with a few squiggles and a straight line. She added sheaths, a nucleus and many, many more details. We students were so focused on taking notes, that few of us noticed that we had just copied a picture of a person complete with smiling mouth, nose and eyes.
The nostalgia of that quietly imaginative moment comes strongly to my mind when I see, real life pictures of nerve cells posted on the online Cell Center Database. Those pictures show how beautiful nerve cells are!
This nerve is a purkinje cell in the brain.
Your nerves are the primary message system of your body. Nerves are bundles of cells that carry electrical signals. The wiring of your computer or car carries electrical signals also but our body is impressively more complex. Between connecting nerve cells, there are microscopic gaps where chemicals transmit the signal to the next nerve. Not only do these chemicals transmit the signal, they can increase, decrease or otherwise change the signal. This gap is called the electrochemical junction and the chemicals are called neurotransmitters.
Your body's most abundant excitatory (signal increasing) neurotransmitters are the amino acids (proteins), glutamate and aspartate. While your body makes all the glutamate and aspartate you need, you also get it naturally from food. Walnuts, mushrooms, grains, tomatoes and grapes are a few foods that are high in glutamate. Seaweed and beans are naturally high in aspartic acid, an amino acid your body uses to make aspartate.
The exciting effect of glutamate and aspartate give our taste buds and our brains a pleasurable feeling, making many of the high glutamate and aspartic acid foods favorite staples in our diets. Without our exciting neurotransmitters, life would be pretty depressing and dull. In fact our bodies would stop working.
Our bodies observe strict laws of balance. Natural foods containing glutamate and aspartate have them bound in fiber, bound in amino acid chains and packaged with other protective nutrients. All this helps them to be distributed to our blood stream in a controlled manner. Specialized cells called astrocytes, collect and dole out glutamate and aspartate to the electrochemical junction in a manner that gets the best action without overdoing it.
It all works beautifully unless - something goes wrong. Excitatory neurotransmitters can be a problem in the following conditions:
1) If tissue is damaged, excessive amounts of glutamate can be released, causing damage to nerve cells. Your brain blood vessels have very tightly packed together cells in the blood vessels of the brain (the blood brain barrier) which prevent many substances from getting to many of the nerves and organs of your brain. Many things can cause the blood brain barrier to be interrupted either briefly or permanently. Fever, head injury, low blood sugar and infections are just a few.
According to a research review in American Journal of Neuroradiology 22, P 1821, 2001."Glutamate excitotoxicity is the final common pathway resulting in neuronal injury for many seemingly unrelated disorders, including ischemia [lack of blood flow], trauma, seizures, hypoglycemia [low blood sugar], hypoxia [lack of oxygen], and some neural degenerative disorders."
There is a lot of research going into ways to protect our nerve cells from the damaging effects of glutamate when we get sick. There is even a drug out now attempting to block the effect of glutamate to prevent progression of alzheimers. Research has also shown magnesium and vitamin C can also be protective.
2) If the body is given refined excitatory neurotransmitters in food or supplements, damage can occur to the nerve cells.
Research has shown that nerves exposed to high levels of glutamate will begin firing rapidly. If the glutamate is not removed, or can not be removed, the nerve will swell up and burst. Not good!
Dr. Olney, an early researcher of the effects of glutamate on nerve cells, made this astounding statement in the Journal of Child Neurology in 1989, "The amount of MSG in a single bowl of commercially available soup is probably enough to cause blood glutamate levels to rise higher in a human child than levels that predictably cause brain damage in immature animals.”
While some dismiss concerns of excitotoxity from food by claiming the blood brain barrier prevents glutamate from reaching the brain, a closer look finds that there are amino acid transport systems in the blood brain barrier that readily move glutamate from our blood stream, into our brain.
A good rule of thumb is to make sure any glutamate and aspartate you give your body is bound in real food, in its naturally grown state and avoid food, supplements and medications with added refined amino acids. Natural foods contain vitamin C, magnesium and a multitude of other properties which help prevent excitotoxicty. Foods, as grown, are carefully designed packages. Adding to or taking away from that design and balance can cause problems. It is always the best plan to eat food as close to its natural state as possible.
For more information on this topic, and find added ingredients to avoid, CLICK HERE to watch a free informational video.
Coming soon- An article about the neurotransmitters that relax your nerves.