Serotonin is an important neurotransmitter, which is a chemical responsible for transmitting nerve impulses between nerve cells. Formed by the pineal gland, which is located in the brain, serotonin is found primarily in the brain, the lining of the digestive tract and in blood platelets.
Function of Serotonin in the Brain
This neurotransmitter affects mood, emotions, sleep and appetite. The concentration of serotonin in the brain is controlled directly by its reabsorption by the nerve cells that produce it. Serotonin is an opiate-like chemical that helps us maintain a happy feeling. It keeps our moods in balance by helping us sleep, calming anxiety and relieving depression.
Consequences of Serotonin Deficiency on Mood
An imbalance in serotonin levels influences mood enough to lead to depression, anxiety and panic attacks. Possible causes of a serotonin deficiency are low brain cell production, not enough tryptophan in the diet and the inability of serotonin to reach the receptor sites. Depression, anxiety and the occurrence of panic attacks adversely affect a person's ability to function normally. Suicide is a potential consequence of major depression. Antidepressant medications know as selective serotonin reuptake inhibitors are effective in reducing the symptoms of depression.
Function of Serotonin in the Gastrointestinal Tract
Serotonin is localized in the cells of the mucosal lining and neurons of the gastrointestinal tract. It inhibits the secretion of gastric acid, controls smooth muscle function and stimulates the production and the release of gastric and colonic mucus. Ninety-five percent of the body's total serotonin concentration is located in the gut.
Consequences of Serotonin Deficiency in the Gastrointestinal Tract
A serotonin imbalance, improper reabsorption and faulty communication in neurotransmission between serotonin and the brain may be possible causes of many gastrointestinal disorders. Irritable bowel syndrome is one disorder linked to serotonin imbalance. Medications that are serotonin receptors effectively stimulate intestinal contractions and reduce the symptoms of abdominal pain and constipation associated with irritable bowel syndrome.
Serotonin in Platelets
Serotonin is found in platelets, which are disk-shaped, colorless components of blood essential to the clotting process. The staff of the website Pharmacorama explains that platelets do not make serotonin but absorb it from plasma. Serotonin released from platelets has a localized effect on the blood vessels, where it is released. Serotonin acts as a vasoconstrictor to prevent bleeding following injury and to aid in the healing process. High levels of serotonin in the blood vessels in the head precipitate migraine headaches.
Food Sources of Tryptophan
Tryptophan is an amino acid that leads to the synthesis of serotonin. Animal sources with the highest concentration of tryptophan include chicken, turkey, lean beef, lamb, salmon, tuna and shrimp. Other food sources include dairy products, bananas, nuts and soybeans.
