OBJECTIVE: The aim of the study was to assess cAMP-dependent endogenous
phosphorylation in platelets from euthymic bipolar patients. METHOD:
Platelets from 10 drug-free euthymic patients with bipolar disorder were
compared with those from 10 age- and sex-matched healthy subjects. Basal
and cAMP-stimulated protein phosphorylation was examined in each group.
RESULTS: Endogenous phosphorylation in both the healthy volunteers and the
bipolar patients was significantly stimulated by cAMP; the major
polypeptides had apparent molecular weights of 38 and 22 kDa. The
cAMP-stimulated 32P incorporation differed between the bipolar patients and
the comparison subjects only in the 22-kDa band. CONCLUSIONS: These data
suggest a possible role of cAMP-dependent protein phosphorylation in the
pathophysiology of bipolar disorder.