Urinary Excretion of 5-Hydroxyindolacetic Acid in Diarrheal States, with Special Reference to Nontropical Sprue

Abstract

URINARY excretion of the serotonin metabolite, 5-hydroxyindolacetic acid, was studied both in normal subjects and in patients with a variety of diarrheal states. Three observations led to this investigation. Circulating 5-hydroxytryptamine (serotonin), which is secreted in large amounts by the tumor, causes the cramping abdominal pain and diarrhea of the malignant carcinoid syndrome.^{1 , 2} Parenterally administered serotonin has a marked effect upon the gut of man and animals.^{3 , 4} The precursor of serotonin, 5-hydroxytryptophan, produces nausea, abdominal cramps and borborygmi in human beings.⁵ Subjects and MethodsTwenty-four-hour specimens of urine were collected from 30 normal adults (house-staff and hospital personnel) and from . . .