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Updated: Jun 26, 2026

A Plate-Based Assay for the Measurement of Endogenous Monoamine Release in Acute Brain Slices
Published on: August 11, 2021
Uptake of 5-hydroxytryptamine by platelets
Abstract:
Human blood platelets were incubated with 5-hydroxytryptamine and with tryptamine and the uptake of each amine measured. The uptake of tryptamine, unlike that of 5-hydroxytryptamine, was linearly related to the concentration of the amine in the surrounding fluid, was similar in amount at 0 degrees and 37 degrees C and varied directly with the pH of the solution. When both amines were present together the uptake of 5-hydroxytryptamine was depressed. The antagonism of tryptamine was found to be competitive, and the possible site of its action is discussed. The effect of a number of other substances on the uptake of 5-hydroxytryptamine by platelets was examined; of these imipramine, cocaine and chlorpromazine were more potent and dihydroergotamine and lysergic acid diethylamide somewhat less potent than tryptamine in inhibiting uptake.
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