Yohimbine and rauwolscine inhibit 5-hydroxytryptamine-induced contraction of large coronary arteries of calf through blockade of 5 HT2 receptors

  title={Yohimbine and rauwolscine inhibit 5-hydroxytryptamine-induced contraction of large coronary arteries of calf through blockade of 5 HT2 receptors},
  author={Alberto Julio Kaumann},
  journal={Naunyn-Schmiedeberg's Archives of Pharmacology},
  • A. Kaumann
  • Published 1 June 1983
  • Biology
  • Naunyn-Schmiedeberg's Archives of Pharmacology
Summary5-Hydroxytryptamine (5 HT)-induced contractions were investigated on cocaine-treated strips of bovine large coronary arteries.1.The α2-adrenoceptor blockers rauwolscine and yohimbine antagonized competitively 5 HT-induced contractions. The estimated equilibrium dissociation constantsKB (−log mol/l) were 7.1 for rauwolscine and 7.3 for yohimbine. The affinity of yohimbine for the receptors mediating the response to 5HT appears to be 10 times higher than for postsynaptic α1-adrenoceptor… 

A paradox: the 5-HT2-receptor antagonist ketanserin restores the 5-HT-induced contraction depressed by methysergide in large coronary arteries of calf

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Vascular effects of ketanserin (R 41 468), a novel antagonist of 5-HT2 serotonergic receptors.

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  • Medicine, Biology
    The Journal of pharmacology and experimental therapeutics
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  • I. Innes
  • Biology, Chemistry
    British journal of pharmacology and chemotherapy
  • 1962
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Actions of serotonin antagonists on dog coronary artery.

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