We modeled the common clinical conditions of human stroke in fully conscious rats through an occlusion of the middle cerebral artery (MCAO) by means of unilateral microinjection of Endothelin-1 (ET1) in the vicinity of the artery (EMCAO model). Since the role of serotonin (5-HT) system in the regulation of the cerebral blood flow has been known for long time and no data are available at present...

In a randomized, double-blind clinical study in 29 patients undergoing elective coronary artery surgery, we assessed the role of ketanserin, an inhibitor of serotonin-induced vasoconstriction and weak alpha 1 sympathetic blocker, in reducing endotoxaemia and postoperative hypermetabolism. Male patients without major organ dysfunction were allocated randomly to receive either ketanserin or place...

A study was performed to see whether ketanserin, a serotonin antagonist, would reduce the raised concentrations of adrenocorticotrophic hormone (ACTH) in patients with Nelson's syndrome. Six patients who had undergone bilateral adrenalectomy for Cushing's disease and who had Nelson's syndrome were given ketanserin 40 mg twice daily and placebo, for at least two months each, in a double blind cr...

The local hemodynamic effects of serotonin (5-hydroxytryptamine; 5-HT) and the selective 5-HT2 antagonist ketanserin were investigated in the forearm of 20 healthy volunteers. Single doses of 5-HT (0.1-80 ng/kg/min) and ketanserin (5-125 ng/kg/min) were administered intra-arterially. The relative alpha 1-adrenergic receptor and 5-HT2 blocking potencies of ketanserin were investigated using intr...

The antihypertensive effect of the selective serotonin antagonist ketanserin was examined in a double-blind, placebo-controlled, parallel group study in 20 patients with essential hypertension. After 7 weeks treatment with ketanserin (mean dose 71 mg/d) there was a significant fall of both systolic and diastolic blood pressure, as compared to placebo, with a peak effect of 19.1/9.1 mmHg lying (...

Aggregating platelets release serotonin, which induces contraction of most vascular smooth muscle by activation of S2-serotoninergic receptors. Serotonin released in the circulation may contribute to the increase in peripheral resistance of hypertension as the responsiveness of blood vessels from hypertensive animals and humans to the vasoconstrictor action of the monoamine is augmented. The da...

The serotonin (5-hydroxytryptamine, 5-HT) antagonist, ketanserin, has a high affinity for 5-HT2-receptors but it also binds to alpha 1-adrenoceptors. The compound (10 mg i.v.) lowered mean arterial pressure by 22% +/- 2% (mean +/- SEM, p less than 0.001) in 30 patients with essential hypertension. Measurements of heart rate, cardiac output, cardiac filling pressures, forearm blood flow, renal b...

To assess the role of the serotonin antagonist ketanserin in the management of hypertension in the elderly, 12 patients with a mean age of 68 years (range 60-79 years) were treated with ketanserin in a randomised double-blind placebo-controlled cross-over trial. Clinic BP, ambulatory BP, renal function, and pharmacokinetics were assessed. The doses of ketanserin used were 40 mg (ten patients) a...

Two patients developed profound hypotension approximately one hour after taking an initial oral dose of ketanserin 40 mg. The reaction appeared similar to that reported with prazosin, and may have been due to the alpha 1-adrenoceptor antagonist action of ketanserin. Both patients were taking regular beta-blocker therapy, which may exacerbate such a reaction.

The effect of topical ketanserin on intraocular pressure (IOP) in normotensive and hypertensive eyes was evaluated. The study was performed on 10 healthy volunteers and 10 glaucomatous patients. Systolic arterial blood pressure (SBP), diastolic arterial blood pressure (DBP), heart rate (HR), IOP, tonographic outflow facility, pupil diameter, corneal thickness, and tear secretion were recorded a...