cAMP signaling pathway in depressed patients with psychotic features.
Abnormalities in protein kinase A (PKA) and Rap1 have recently been reported in depressed patients. The aim of the present study was to investigate the levels of these proteins in platelets from untreated unipolar and bipolar depressed patients with psychotic features. The levels PKA and Rap1 were assessed by Western blot analysis and immunostaining in 37 drug-free patients and 29 healthy subjects. Both unipolar and bipolar patients with psychotic depression have significantly lower levels of platelet regulatory type I and higher levels of catalytic subunits of PKA than controls, whereas the levels of regulatory type II were higher only in psychotic unipolar patients. No significant differences were found in the immunolabeling of both Rap1 and actin among groups. These findings support the idea that besides nonpsychotic depression, abnormalities of PKA could be linked, albeit in a somewhat different way, with psychotic depression.
Perez
J
J
Istituto Scientifico HSR, Department of Neuropsychiatry, School of Medicine, University Vita-Salute, Milan, Italy. perez.jorge@hsr.it
Tardito
D
D
Racagni
G
G
Smeraldi
E
E
Zanardi
R
R
D000328:Adult; D001714:Bipolar Disorder / Q000378:metabolism*; D001792:Blood Platelets / Q000737:chemistry / Q000201:enzymology; D015153:Blotting, Western; D000242:Cyclic AMP / Q000378:metabolism*; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases / Q000032:analysis / Q000378:metabolism; D003866:Depressive Disorder / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015398:Signal Transduction / Q000502:physiology*; D020827:rap1 GTP-Binding Proteins / Q000032:analysis / Q000378:metabolism
D000242:Cyclic AMP; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases; D020827:rap1 GTP-Binding Proteins