Pharmacological characterization of 5-hydroxytryptamine3 receptors in murine brain and ileum using the novel radioligand [3H]RS-42358-197: evidence for receptor heterogeneity.

Previous studies have demonstrated species-specific differences in 5-hydroxytryptamine3 (5-HT3) receptors, but unequivocal evidence of 5-HT3 receptor subtypes, within a species, has not yet been obtained. The purpose of the current study was to test for heterogeneity in 5-HT3 receptors in murine tissues. 5-HT3 receptors in membranes derived from brain cerebral cortex of CD-1, C57Bl/6, and Swiss Webster mice and ileum of CD-1 mice were labeled with the 5-HT3 receptor antagonist [3H]RS-42358-197.

The interaction of parafluorohexahydrosiladiphenidol at muscarinic receptors in vitro.

1. The antagonistic actions of parafluorohexahydrosiladiphenidol (pFHHSiD) at muscarinic receptors has been studied in cardiac muscle, smooth muscle and cell culture preparations. In this paper, the classification scheme of Doods et al.

The interaction of hexamethonium with muscarinic receptor subtypes in vitro.

1. The action of hexamethonium has been studied at a range of muscarinic receptors in vitro by use of both functional and radioligand binding studies. 2.

The human astrocytoma cell line 1321 N1 contains M2-glandular type muscarinic receptors linked to phosphoinositide turnover.

1. Muscarinic receptors present in the human astrocytoma cell line 1321 N1 were characterized in radioligand binding studies and in functional studies of carbachol-stimulated phosphatidylinositol (PI) turnover. 2.

Functional and direct binding studies using subtype selective muscarinic receptor antagonists.

1. Muscarinic receptor antagonists were examined in direct binding studies on guinea-pig cardiac and cortical muscarinic receptors. Pirenzepine, dicyclomine and hexahydroadiphenine were shown to be selective ligands for the putative M1-muscarinic receptor.