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.
About half of those who have mononucleosis have enlargement of the spleen, usually 2 to 3 weeks after they are infected. The incubation periodâthe time it takes symptoms to appear after a person becomes infected with the virusâcan be 4 to 6 weeks.Symptoms of mononucleosis usually last for 1 to 4 weeks, but it might take as long as 2 months before you feel well enough to resume all of your normal activities.he most common symptoms of mononucleosis are fever, sore throat, and swollen lymph glands in the neck, under the arms, and in the groin area. Other symptoms include the following: 1  fatigue. 2  muscle aches or weakness.