5-hydroxytryptamine and precapillary vessels.

J M Van Nueten

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PubMed · 6295823

5-hydroxytryptamine and precapillary vessels.

J M Van Nueten

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Abstract

The complexity of the vascular effects of 5-hydroxytryptamine (5-HT) is illustrated by differences in sensitivity to the amine among arterial tissues of different origin. The interaction of 5-HT with 5-HT2 receptors is inhibited by specific antagonists such as ketanserin and methysergide. Such compounds also inhibit the contractile responses to endogenous 5-HT released from aggregating platelets. The vasodilator component of the response to 5-HT can be unmasked in the presence of serotonergic blockade, provided the antagonist used has no partial agonistic properties. 5-HT augments (amplifies) the vasoconstrictor responses to adrenergic and nonadrenergic neurohumoral mediators. The amplifying effect of the monoamine is prevented by 5-HT2-serotonergic antagonists such as ketanserin.

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Angiotensin II Animals Dinoprost Drug Interactions Histamine Ketanserin Methysergide Norepinephrine Piperidines Prostaglandins F Receptors, Adrenergic, alpha Serotonin Vasoconstriction Journal Article Research Support, Non-U.S. Gov't Review

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J M Van Nueten. 1983. 5-hydroxytryptamine and precapillary vessels.. https://pubmed.ncbi.nlm.nih.gov/6295823/

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