title: Platelet alpha-2-adrenergic dysfunction in negative symptom schizophrenia: a preliminary study.
abstract: The specific binding to platelet membranes (Bmax) of 3H-clonidine, an alpha-2 agonist, and 3H-yohimbine, an alpha-2 antagonist, was measured in nine drug-free male schizophrenic patients and repeated after 2 weeks of chlorpromazine (CPZ) treatment. Patients with a lower pretreatment Bmax for 3H-clonidine showed a significantly smaller change in Bmax after treatment, less improvement in their clinical state, as indicated by the change in the Global Assessment Scale (GAS), and a lower posttreatment GAS. Also, they had a significantly higher score for negative symptoms on the Affect Rating Scale both before and after treatment. These findings suggest that schizophrenic patients with relatively subsensitive platelet alpha-2-adrenergic receptors, as measured by 3H-clonidine binding, tend to have more negative symptoms and a diminished alpha receptor binding response and diminished clinical response to CPZ. There were no clinical correlations to 3H-yohimbine binding.
authors.forename: J
authors.initials: J
authors.lastname: Rosen
authors.forename: K R
authors.initials: KR
authors.lastname: Silk
authors.forename: H E
authors.initials: HE
authors.lastname: Rice
authors.forename: C B
authors.initials: CB
authors.lastname: Smith
mesh_terms: D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002746:Chlorpromazine / Q000627:therapeutic use; D003000:Clonidine / Q000097:blood*; D006801:Humans; D007700:Kinetics; D011569:Psychiatric Status Rating Scales; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000378:metabolism*; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy; D012565:Schizophrenic Psychology; D015016:Yohimbine / Q000097:blood
chemical_list: D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D003000:Clonidine; D002746:Chlorpromazine