The radioligand binding characteristics of 125I-R-(-)4-iodo-2,5-dimethoxyphenylisopropylamine [125I-R-(-)DOI] and 3H-ketanserin were compared in rat and bovine cortical membranes. In rat cortex, 125I-R-(-)DOI labels a relatively low density of binding sites (Bmax = 2.5 +/- 0.2 pmol/gm tissue) with high affinity (KD = 0.63 +/- 0.09 nM). In bovine cortex, specific binding of 125I-R-(-)DOI represe...

Thirty patients who developed arterial hypertension following coronary artery bypass grafting, despite sedation, were treated randomly with sodium nitroprusside (SNP), ketanserin or urapidil. All drugs significantly decreased arterial pressure. Two patients were withdrawn because hypertension failed to respond to ketanserin. Significant tachycardia was noted only in the SNP group. An increase i...

The binding of [3H]ketanserin to goldfish and rabbit retinal membrane preparations and the possible role of 5-HT2A receptors in the in vitro outgrowth from goldfish retina were evaluated. Saturation experiments indicated a high-affinity binding site, and positive cooperativity for both tissues. The 5-HT2A/2C agonist (+/-)-2,5-dimetoxy-4-iodoamphetamine and serotonin inhibited outgrowth from gol...

Increased release of serotonin (5-hydroxytryptamine, 5-HT) can play a significant role in the development of acute respiratory failure. The hemodynamic effects of ketanserin, a selective inhibitor of 5-HT2 receptors, were studied in eight patients who developed acute respiratory insufficiency after an episode of circulatory shock. Administration of ketanserin was associated with reductions in s...

The serotonin receptor blocker ketanserin was given orally in a double blind crossover study to 10 patients with connective tissue disorders and Raynaud's phenomenon. Eight of the 10 patients improved clinically on ketanserin and none on placebo. Digital blood flow was assessed with laser Doppler flowmetry (LDF), photoplethysmography, and skin temperature measurements. Laser Doppler flowmetry w...

The 5-hydroxytryptamine (5-HT)1B/1D receptor subtypes are involved in the regulation of 5-HT release and have gained particular interest because of their apparent role in migraine. Although selective antagonists for both receptor subtypes recently have been developed, the receptor domains involved in the pharmacological specificity of these antagonists are defined poorly. This was investigated ...