Vascular pharmacology of 5-hydroxytryptamine in humans

Forty yeas after its discovery the role of 5-hydroxytryptaine (5-HT) in the regulation of vascular tone in man still remains rather obscure. Soon after synthetic 5-HT became available it was shown that this monoamine influences vascular tone in a complex manner. Depending on the type of blood vessel and species investigate, as well as on the dose and route of administration, 5-HT was able to induce either vasodilatation or vasoconstriction [1, 2].