Serotonin (24 hour urine)

General Information

Serotonin Is a chemical involved in the transmission of messages between nerve cells. The test measures the amount of serotonin in the blood.

Serotonin is obtained from the amino acid tryptophan. It is produced as needed by special cells of the nervous system, mainly the brain, as well as the bronchi and gastrointestinal tract. More than 90% of serotonin in the blood is found in platelets.

Serotonin is metabolized in the liver and its metabolites, mainly 5-HIAA (5-hydroxyindoleacetic acid), are excreted in the urine.

Serotonin affects all functions of the human body - from emotions to physical activity:

• Promotes control of peristalsis;
• Regulates mood;
• Controls the sleep-wake cycle;
• Participates in blood clotting, etc.

Normally, serotonin is present in small amounts in the blood and therefore in the urine. Large amounts of serotonin and 5-HIAA can be produced continuously or some intermittently Carcinoid tumor By. Carcinoid tumors are slow-growing masses that can form in the gastrointestinal tract (especially the appendix) and lungs, although they can affect other organs as well. Serotonin produced by carcinoid tumors can cause facial redness, diarrhea, rapid heartbeat, and wheezing, especially when the tumor has spread to the liver. This group of signs and symptoms is called Carcinoid syndrome.