What many people do not understand is that serotonin also plays a role in gastrointestinal disorders. In fact, the majority of our serotonin is produced in the gut, roughly 95%. Serotonin is produced in the enterochromaffin cells (EC) in the intestinal mucosa.Serotonin is produced, and then it bonds with its receptors.hat many people do not understand is that serotonin also plays a role in gastrointestinal disorders. In fact, the majority of our serotonin is produced in the gut, roughly 95%. Serotonin is produced in the enterochromaffin cells (EC) in the intestinal mucosa.
Early signs of mono in teens: 1  Early symptoms of viral infectious mono disease in teens are similar to flu symptoms. 2  Fever with shivering. 3  Teens may get headaches, severe fatigue, and pain in the muscles.  Sore throat with swollen tonsils, a common flu symptom, is also seen in mono.
The most common symptoms of mono are: 1  Fever, which may range from 101Â°F (38.3Â°C) to 104Â°F (40Â°C) , and chills. 2  Sore throat, often with white patches on the tonsils (which may look like strep throat). 3  Swollen lymph nodes all over the body, especially the lymph nodes in the neck.4  Swollen tonsils.5  Headache or body aches.ot everyone infected with the virus that causes mono (Epstein-Barr virus, or EBV) has symptoms. This is especially true for young children, who may have a fever but no other symptoms. People ages 15 to 24 are most likely to have obvious symptoms.