Increased platelet membrane [3H]-LSD binding in patients on chronic neuroleptic treatment.

Journal article

Using a [3H]-lysergic acid diethylamide [( 3H]-LSD) binding technique, platelet 5-hydroxytryptamine (5-HT) receptor number and affinity were compared in schizophrenics treated with depot thioxanthenes and phenothiazines and controls. There was an approximately 30% increase in platelet receptor number (Bmax) in the patient group. There was a decrease in affinity (increase in Kd) of about 30% in the patient group. This was probably due to the persistence of the neuroleptic in the platelet membrane preparation. There was a weak positive correlation between receptor number and total neuroleptic dosage. The increased number of 5-HT receptors is consistent with the previously reported enhancement of 5-HT-induced platelet aggregation in patients treated with long-term phenothiazines and thioxanthenes. Our findings are compatible with 5-HT up-regulation in human platelets produced by depot neuroleptic therapy. It is not known whether parallel changes may be occurring in brain 5-HT receptors.

Authors: Schächter, M; Geaney, D; Grahame-Smith, D; Cowen, P; Elliott, J

• Publication status: Published
• Journal: British journal of clinical pharmacology
• Volume: 19
• Issue: 4
• Pages: 453-457
• Publication date: 1985-04-01
• DOI: 10.1111/j.1365-2125.1985.tb02670.x
• EISSN: 1365-2125
• ISSN: 0306-5251
• Language: English
• Keywords: Middle Aged; Humans; Sex Factors; Blood Platelets; Aging; Kinetics; Receptors, Serotonin; Lysergic Acid Diethylamide; Antipsychotic Agents; Cell Membrane; Adult; Male; Schizophrenia; Female; Time Factors