title: G-protein level quantification in platelets and leukocytes from patients with panic disorder.
abstract: The objective of our study was to investigate if there are abnormalities in signal transducing G proteins in patients with panic disorder. We utilized selective antibodies to quantitate the levels of the G protein alpha subunits that regulate adenylyl cyclase activity (G alpha s and G alpha i2) and phosphoinositide turnover (G alpha q/11) in platelet membranes (and leukocyte membranes for G alpha s), and also carried out pertussis toxin (PT) catalyzed [32P]ADP-ribosylation in platelet membranes from a group of 13 untreated panic disorder patients, 10 untreated social phobia patients, and 12 healthy subjects. There were no significant differences among the three groups in the immunolabeling of G alpha s in platelets or leukocytes, or in the immunolabeling of G alpha i1/2, G alpha q/11, or PT-catalyzed [32P]ADP-ribosylation in platelets. Within the constraints imposed by using peripheral blood cells to reflect brain composition, our results do not provide support for G protein abnormalities in patients with panic disorder. These results contrast with those obtained using identical methodology in bipolar affective disorder, where elevated G alpha s in leukocytes has been reported (Manji et al. 1995).
authors.affiliation: Department of Psychiatry, University of California, San Diego 92093-0603, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Stein
authors.forename: G
authors.initials: G
authors.lastname: Chen
authors.forename: W Z
authors.initials: WZ
authors.lastname: Potter
authors.forename: H K
authors.initials: HK
authors.lastname: Manji
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000097:blood; D037361:Adenylate Cyclase Toxin; D000262:Adenylyl Cyclases / Q000097:blood; D000328:Adult; D001008:Anxiety Disorders / Q000097:blood; D001792:Blood Platelets / Q000378:metabolism*; D015153:Blotting, Western; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D005260:Female; D019204:GTP-Binding Proteins / Q000097:blood*; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D016584:Panic Disorder / Q000097:blood*; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000097:blood; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D037361:Adenylate Cyclase Toxin; D010716:Phosphatidylinositols; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases