title: Platelet shape change in patients with psychiatric disorders and treated with phenothiazines, thioxanthines, butyrophenones, benzodiazepines, tricyclic antidepressants and beta-adrenergic blocking agents.
abstract: Platelet shape change responses to 5-hydroxytryptamine were examined in 11 normal subjects and in 78 patients with psychiatric disorders receiving one or more of the following classes of drug: phenothiazine, thioxanthine, butyrophenone, tricyclic antidepressant, benzodiazepine or lithium. Approximately 37% of patients received a single drug, the remainder up to 4 other compounds in addition to the main drug. Platelet shape change induced by 5-hydroxytryptamine (0.25, 2.5 or 25 nmol/ml) was significantly inhibited in patients treated with phenothiazines, thioxanthines and butyrophenones (haloperidol). Tricyclic antidepressants, lithium and benzodiazepines had no effect on 5-hydroxytryptamine-induced shape change. In contrast, a combination of lithium plus chlorpromazine significantly enhanced platelet shape change. Potentiation of noradrenaline-induced aggregation was approximately 50% in normal subjects. This degree of potentiation was not altered in the drug-treated patients although there were quantitative reductions in magnitude of response. Platelet shape change in addition to platelet aggregation may be used as a pharmacological tool to investigate the aetiology of psychiatric disorders and, perhaps eventually, to monitor the clinical efficacy of drug therapy.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D014151:Anti-Anxiety Agents / Q000627:therapeutic use*; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use*; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D001569:Benzodiazepines; D001792:Blood Platelets / Q000187:drug effects / Q000648:ultrastructure*; D002090:Butyrophenones; D005260:Female; D006801:Humans; D008094:Lithium / Q000627:therapeutic use; D008297:Male; D001523:Mental Disorders / Q000097:blood / Q000188:drug therapy*; D008875:Middle Aged; D010640:Phenothiazines; D012701:Serotonin / Q000494:pharmacology; D013892:Thioxanthenes / Q000627:therapeutic use*
chemical_list: D000319:Adrenergic beta-Antagonists; D014151:Anti-Anxiety Agents; D000929:Antidepressive Agents, Tricyclic; D014150:Antipsychotic Agents; D002090:Butyrophenones; D010640:Phenothiazines; D013892:Thioxanthenes; D001569:Benzodiazepines; D012701:Serotonin; D008094:Lithium