SOME OBSERVATIONS ON THE ESTIMATION OF TRYPTAMINE IN TISSUES

SUMMARY The method of Hess and Udenfriend (1959) for the estimation of tryptamine in tissues, is demonstrated to allow the carry over of tryptophan to the final extract, resulting in falsely high values for the amine. A modification of the original method is described, incorporating ion-exchange chromatography, which gives complete separation of these components. Using this method, tryptamine is found neither in the brain of normal guinea pigs, nor in animals treated with l-tryptophan. It is found only when l-tryptophan is administered following pretreatment with an amine oxidase inhibitor.