The effects of intrathecal ketanserin and phentolamine on heart rate and arterial blood pressure in the rat
Ketanserin lowers arterial blood pressure in both animals and humans, but the mechanism of its antihypertensive action is in debate [see 1]. In general, it is now accepted that ketanserin, at least partly, lowers blood pressure by α 1-adrenoceptor blockade [2–4]. However, additional mechanisms, such as the blockade of 5-HT2 receptor-mediated amplification of the vasoconstrictor action of noradrenaline by 5-hydroxytryptamine (5-HT) [see 5], direct vasodilatation  and a CNS action [6–8], have also recently been implicated. In this investigation the effects of intrathecal administration of ketanserin and phentolamine on arterial blood pressure and heart rate in normotensive anaesthetized rats have been studied.
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- 3.Kalkman HO, Timmermans PBMWM, Van Zwieten PA (1982): Characterization of the antihypertensive properties of ketanserin (R 41486) in rats. J Pharmacol Exp Ther 22: 227–231.Google Scholar
- 5.Vanhoutte PM, Amery A, Birkenhäger W, Breckenridge A, Bühler F, Distler A, Dormandy J, Doyle A, Frohlich E, Hansson L, Hedner T, Hollenberg N, Jensen H-E, Lund-Johansen P, Meyer P, Opie L, Robertson I, Safar M, Schalekamp M, Symoens J, Trap-Jensen J, Zanchetti A (1988): Serotonergic mechanisms in hypertension: Focus on the effects of ketanserin. Hypertension 11: 111–133.PubMedCrossRefGoogle Scholar