What’s A Neurotransmitter?

Neurotransmitters are molecules that regulate brain function. They are chemicals which relay messages from nerve to nerve both within the brain and outside the brain. They also relay messages from nerve to muscle, lungs, and intestinal tracts. They can accentuate emotion, thought processes, joy, elation and also fear, anxiety, insomnia and that terrible urge to over indulge in food, alcohol, drugs, etc. 

In short, neurotransmitters are used all over the body to transmit information and signals. They are manufactured and used by neurons (nerve cells) and are release into the synaptic clefts between the neurons.

These brain chemicals communicate information throughout our brain and body. They relay signals between nerve cells, called “neurons.” The brain uses neurotransmitters to tell your heart to beat, your lungs to breathe, and your stomach to digest.  They can also affect mood, sleep, concentration, weight, and can cause adverse symptoms when they are out of balance. Neurotransmitter levels can be depleted many ways. As a matter of fact, it is estimated that 86% of Americans have suboptimal neurotransmitter levels.  Stress, poor diet, neurotoxins, genetic predisposition, drug (prescription and recreational), alcohol and caffeine usage can cause these levels to be out of optimal range.

There are two kinds of neurotransmitters – INHIBITORY and EXCITATORY. Excitatory neurotransmitters are not necessarily exciting – they are what stimulate the brain. Those that calm the brain and help create balance are called inhibitory. Inhibitory neurotransmitters balance mood and are easily depleted when the excitatory neurotransmitters are overactive.

Inhibitory Neurotransmitters

• SEROTONIN is an inhibitory neurotransmitter – which means that it does not stimulate the brain.  Adequate amounts of serotonin are necessary for a stable mood and to balance any excessive excitatory (stimulating) neurotransmitter firing in the brain.  If you use stimulant medications or caffeine in your daily regimen – it can cause a depletion of serotonin over time.  Serotonin also regulates many other processes such as carbohydrate cravings, sleep cycle, pain control and appropriate digestion.  Low serotonin levels are also associated with decreased immune system function.
• GABA is an inhibitory neurotransmitter that is often referred to as “nature’s VALIUM-like substance”.  When GABA is out of range (high or low excretion values), it is likely that an excitatory neurotransmitter is firing too often in the brain.  GABA will be sent out to attempt to balance this stimulating over-firing.
• DOPAMINE is a special neurotransmitter because it is considered to be both excitatory and inhibitory.  Dopamine helps with depression as well as focus, which you will read about in the excitatory section.

Excitatory Neurotransmitters

• DOPAMINE is our main focus neurotransmitter.  When dopamine is either elevated or low – we can have focus issues such as not remembering where we put our keys, forgetting what a paragraph said when we just finished reading it or simply daydreaming and not being able to stay on task.  Dopamine is also responsible for our drive or desire to get things done – or motivation.  Stimulants such as medications for ADD/ADHD and caffeine cause dopamine to be pushed into the synapse so that focus is improved.  Unfortunately, stimulating dopamine consistently can cause a depletion of dopamine over time.
• NOREPINEPHRINE is an excitatory neurotransmitter that is responsible for stimulatory processes in the body.  Norepinephrine helps to make epinephrine as well.  This neurotransmitter can cause ANXIETY at elevated excretion levels as well as some “MOOD DAMPENING” effects.  Low levels of norepinephrine are associated with LOW ENERGY, DECREASED FOCUS ability and sleep cycle problems.
• EPINEPHRINE is an excitatory neurotransmitter that is reflective of stress.  This neurotransmitter will often be elevated when ADHD like symptoms are present.  Long term STRESS or INSOMNIA can cause epinephrine levels to be depleted (low).  Epinephrine also regulates HEART RATE and BLOOD PRESSURE.

How do we measure neurotransmitters?

Normally the neurotransmitter is released in response to an electric signal. After binding to the receptor site on the second neuron, the chemical is then recycled. However, only about 60% of the neurotransmitter is recycled. The rest is carried away in the blood stream and excreted in the urine. We can measure urinary levels of neurotransmitters, and get a good idea of their levels within the body.

We measure neurotransmitters directly. It has been found that blood and saliva levels are not particularly useful. Some of the neurotransmitters, epinephrine in particular, have wildly fluctuating levels depending on the person’s sate of mind. (If we are approaching them with a needle to draw blood, the levels will be very high within a few seconds, so blood levels do not give us a picture of the person’s rising neurotransmitter levels.)

Urine levels seem to be representative of what is actually going on in the system.

When we see low urinary levels we can be sure that the body’s stores are low. When we see high urinary levels, the issue is more confusing. In over 90% of cases we can be sure that although levels are apparently high, this only relates to biological activity of the hormone. In actual fact, the total body stores are almost certainly low.

We see this particularly in people who are taking antidepressant medication, especially serotonin reuptake inhibitors like Prozac and Paxil. These medications prevent the nerve cells from taking Serotonin back out of the system (hence the name, re-uptake inhibitors).

However, since the levels are high at the synaptic junction, the body thinks that the levels are high overall, and makes every effort to get rid of as much serotonin as possible. Since the neurotransmitters are excreted in the urine, we therefore see high urinary levels. Not only does the body try to get rid of the neurotransmitters, it also stops making them, in an effort to reduce the levels at the synaptic junction. In the long run, total body stores are depleted, and eventually the urine levels will fall.

Highly depressed moody people are extremely low in serotonin and norepinephrine, but will probably have high urinary levels because they are losing so much at any given point in time.

If they have insomnia, it is likely that their dopamine and/or PEA levels is high.

Highly agitated anxious irritated people will probably have high epinephrine, norepinephrine and dopamine, and relatively low serotonin levels. They may also have markedly elevated PEA levels.

In addition, the sex hormones influence multiple neurotransmitters. Estrogen has an anti-dopamine effect, in addition to inducing the formation of new synapses.

Progesterone increases the effect of GABA and reduces neurotransmitter activity. Estradiol decreases the level of the enzyme which inactivates the serotonin and dopamine (monoamine oxidase, MAO), thus effectively increases the effects of serotonin and dopamine, where progesterone decreases their effects.

DHEA enhances the effect of serotonin and norepinephrine, thus it enhances cognitive function and reduces depression. Cortisol inhibits the release of catecholamines, and increases the effect of GABA, thus reducing anxiety.

TREATING NEUROTRANSMITTER IMBALANCES:

1. We can increase our dietary intake of tryptophan. American diets tend to be high in carbohydrate and low in protein.
2. We can increase our amount of exercise. Exercise leads to more efficient use of insulin, thus reducing insulin resistance and decreasing the amount of food which is stored as fat. When the cells process nutrients better, they make neurotransmitters better.
3. Reduce our intake of caffeine and alcohol. Caffeine makes the body think is it under stress, which raises the cortisol level, raises the insulin level, and causes carbohydrates to be deposited as fat.  Alcohol will deplete seretonin levels over time.
4. Make sure that blood chemistry is in balance.
5. We can supplement the needed amino acids and cofactors,so that the body can make the required neurotransmitters.

MIMICS OF DEPRESSION:

• Hypothyroidism can cause a picture similar to depression, and is easily correctable.
• Vitamin B12 and folate deficiencies can also cause a depression like mimic.