Biology of Depression and Anxiety–by Allison Nabours, ND, LM

Imbalances in communication between the brain and the body can have serious effects to your health both physically and mentally. Depression, anxiety and other mood disorders are thought to be in part related to imbalances with neurotransmitters. The four neurotransmitters that are thought to play a major role in regulating mood are Serotonin, Dopamine, GABA and Norepinephrine. Each person has a unique neurochemistry that factors in to their state of mental health. In addition, these four aren’t the only players in the neurotransmitter soup that affects one’s mood. For example, levels of histamine, PEA, glycine, and glutamate also affect mood. This is why many patients experience extreme frustration when trying to find either the right supplemental support for their neurotransmitters or the correct medication. I would like to explain the function of the major neurotransmitters to shed a light on the multitude of factors that influence the biology of mental health.
Serotonin is an inhibitory neurotransmitter in the brain that has an enormous influence over many brain functions. It is synthesized, from the amino acid L-tryptophan, in brain neurons and stored in vesicles. The functions of serotonin are numerous and appear to involve control of appetite and digestion, sleep cycle, pain control, memory and learning, temperature regulation, mood, behavior (including sexual and hallucinogenic behavior), cardiovascular function, muscle contraction, endocrine regulation, and depression. 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.  Low serotonin levels are also associated with decreased immune system function.
Norepinephrine also known as noradrenaline is an excitatory neurotransmitter that is produced by the adrenal medulla or made from dopamine. High levels of norepinephrine are linked to anxiety, stress, high blood pressure, and hyperactivity. Low levels are linked to lack of energy, focus, and motivation.

Epinephrine also known as adrenaline is a neurotransmitter and hormone essential to metabolism. It regulates attention, mental focus, arousal, and cognition. It also inhibits insulin excretion and raises the amounts of fatty acids in the blood. Epinephrine is made from norepinephrine and is released from the adrenal glands. Low levels have been correlated with fatigue, lack of focus, and difficulty losing weight. High levels have been linked to sleep problems, anxiety and ADHD.

Dopamine is responsible for motivation, interest, and drive. It is associated with positive stress states such as being in love, exercising, listening to music, and sex . When we don’t have enough of it we don’t feel alive, we have difficulty initiating or completing tasks, poor concentration, no energy, and lack of motivation. Dopamine also is involved in muscle control and function. Low Dopamine levels can drive us to use drugs (self medicate), alcohol, smoke cigarettes, gamble, and/or overeat. High dopamine has been observed in patients with poor GI function, autism, mood swings, psychosis, and children with attention disorders.

GABA (Gamma amino butyric acid) is the major inhibitory neurotransmitter in the central nervous system. It helps the neurons recover after transmission, reducing anxiety and stress. It regulates levels of norepinephrine, adrenaline, dopamine, and serotonin, and is therefore a significant mood modulator.
I would like to emphasize that it is important in both depression and anxiety to understand your unique neurotransmitter picture. This can be done in several ways including a complete history of your mental health including a history of supplement and medication usage and their effect on mood and behavior as well as specific neurotransmitter testing that is done by testing levels within your urine. Mental health is a very complex and important component to your overall health. If you are suffering from mood disorders including depression and anxiety we can help you understand your unique picture in order to get the help you deserve.