Increased G alpha q/11 immunoreactivity in postmortem occipital cortex from patients with bipolar affective disorder.
As disturbances in guanine nucleotide binding (G) protein-coupled phosphoinositide second messenger systems have been implicated in bipolar disorder, we examined whether the abundance of G alpha q/11 and phospholipase C (PLC)-beta 1 two key transducing proteins in this signaling pathway, are altered in this disorder. Compared with the controls, immunoreactive levels of G alpha q/11 were significantly elevated by 62% (p = .047) in occipital cortex of bipolar subjects. A similar increase (52%) in the PLC-beta 1 immunolabeling was also found in the occipital cortex of the bipolar subjects, but only reached marginal statistical significance (p = .07). In contrast, frontal and temporal cortex G alpha q/11 or PLC-beta 1 immunolabeling did not differ between bipolar and control subjects. Cerebral cortical immunoreactive levels of G beta 1 or G beta 2, included as a negative control, were not different between comparison groups. These findings support and extend earlier observations suggesting that disturbances in G protein-coupled second messenger signaling pathways may play an important role in the pathophysiology of bipolar affective disorder.
Mathews
R
R
Section of Biochemical Psychiatry, Clarke Institute of Psychiatry, Toronto, Ontario, Canada.
Li
P P
PP
Young
L T
LT
Kish
S J
SJ
Warsh
J J
JJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001714:Bipolar Disorder / Q000378:metabolism*; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000378:metabolism*; D011180:Postmortem Changes; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000502:physiology; D010738:Type C Phospholipases / Q000378:metabolism
D010738:Type C Phospholipases; D019204:GTP-Binding Proteins