LCEC analysis of 5-hydroxytryptamine and norepinephrine in the human gastrointestinal tract

The mucosal content of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) in different parts of the human gastrointestinal tract has been studied. Peroperative biopsies of normal mucosa were collected during various gastrointestinal operations. The amines were extracted and assayed by liquid chromatography with electrochemical detection (LCEC). The concentration of 5-HT was generally approximately 12 times higher than the NE concentration and the highest concentration for both amines was observed in the duodenum, 14 micrograms/g and 1.5 micrograms/g wet weight for 5-HT and NE respectively.