Autoradiographic studies of RP 62203, a potent 5-HT2 receptor antagonist. Pharmacological characterization of [3H]RP 62203 binding in the rat brain.

The binding properties and localization of [3H]RP 62203, a novel ligand for 5-HT2 receptors, were investigated on rat brain sections. The specific binding of this 5-HT2 receptor antagonist was reversible and could be displaced by ritanserin (1 microM). Saturation experiments revealed a single class of binding sites with a KD of 0.

Autoradiographic studies of RP 62203, a potent 5-HT2 receptor antagonist. In vitro and ex vivo selectivity profile.

In this study, quantitative autoradiography was used to determine the selectivity of RP 62203, a novel naphtosultam derivative, for 5-HT2 receptors in vitro and ex vivo, using [125I]7-amino-8-iodo-ketanserin ([125I]AMIK) and [3H]mesulergine as radioligands. The density of [125I]AMIK or [3H]mesulergine binding sites was determined by quantitative image analysis. In in vitro experiments, RP 62203 displaced [125I]AMIK from 5-HT2 receptors with an IC50 of 0.

Arteritis due to Salmonella with aneurysm formation: two cases.

Although arterial infection due to Salmonella is rare, it remains one of the most common causes of primary mycotic aneurysms. The presentation is one of sepsis, cultures positive for Salmonella and rapid expansion or rupture of the aneurysm. The authors' experience at Victoria Hospital, London, Ont.

2-Amino-6-trifluoromethoxy benzothiazole, a possible antagonist of excitatory amino acid neurotransmission--II. Biochemical properties.

Two models have been chosen to study the effect of 2-amino-6-trifluoromethoxy benzothiazole (PK 26124) on excitatory amino acid neurotransmission: the pool of cyclic guanosine monophosphate (cGMP) in the cerebellum and the release of acetylcholine in the striatum and olfactory tubercles. The release of acetylcholine induced by N-methyl-DL-aspartate in the striatum and olfactory tubercles was antagonized by PK 26124 which was less potent on the release of acetylcholine induced electrically. The increase in levels of cGMP in the cerebellum induced by excitatory amino acids such as glutamate and quisqualate was antagonized by PK 26124, but the drug was inactive against N-methyl-DL-aspartate, L-aspartate, kainate and cysteine sulphinate.