title: In vitro effects of psychotropic agents on the microviscosity of platelet membranes.
abstract: Normal platelet membranes were exposed in vitro to a variety of psychotropic agents, including chlorpromazine, fluphenazine, haloperidol, imipramine, and lithium. Changes in microviscosity of the hydrocarbon layer of the drug-exposed membranes were determined by steady-state fluorescence polarization measurements, employing the fluorescent probe 1,6-diphenyl 1,3,5-hexatriene (DPH). Concentrations of the phenothiazines chlorpromazine and fluphenazine above 200 nM produced significant increases in microviscosity, while haloperidol produced a small but consistent decrease in microviscosity in the concentration range of 200 nM to 200 microM. Imipramine and lithium were without effect. The phenothiazine-induced increase in microviscosity was apparently dependent upon the structure of the phenothiazine nucleus; side chain structure was less important to this effect.
mesh_terms: D001792:Blood Platelets / Q000187:drug effects*; D001809:Blood Viscosity; D002462:Cell Membrane / Q000187:drug effects; D002746:Chlorpromazine / Q000494:pharmacology; D005476:Fluphenazine / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D007099:Imipramine / Q000494:pharmacology; D066298:In Vitro Techniques; D008094:Lithium / Q000494:pharmacology; D011619:Psychotropic Drugs / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence
chemical_list: D011619:Psychotropic Drugs; D008094:Lithium; D006220:Haloperidol; D007099:Imipramine; D005476:Fluphenazine; D002746:Chlorpromazine