Br J Pharmacol Chemother. 1961 Jun;16(3):284-95. doi: 10.1111/j.1476-5381.1961.tb01087.x.
British journal of pharmacology and chemotherapy
R S Stacey
PMID: 19108152 PMCID: PMC1482019 DOI: 10.1111/j.1476-5381.1961.tb01087.x
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.
