Effect of lithium on phosphoinositide metabolism in human brain: a proton decoupled (31)P magnetic resonance spectroscopy study.
BACKGROUND
The objective of our study was to evaluate whether lithium increases brain phosphomonoester (PME) levels in human subjects.


METHODS
Proton decoupled (31)P magnetic resonance spectra were obtained from eight healthy volunteers before and after the administration of lithium carbonate, 450 mg b.i.d., for 7 and 14 days.


RESULTS
Pairwise comparisons of the mole percent PME revealed a significant increase from baseline at day 7 and day 14 of lithium administration.


CONCLUSIONS
An increase in PME concentration with 7 and 14 days of lithium administration in the human brain in vivo was observed. Because the inositol-1-monophosphate contributes to the PME peak, this result suggests that some of the initial actions of lithium may occur through a reduction of myo-inositol, which in turn may initiate a cascade of secondary changes at different levels of signal transduction process and gene expression in brain, effects that are ultimately responsible for the therapeutic benefits of lithium.
Yildiz
A
A
Dokuz Eylul Medical School, Department of Psychiatry, Izmir, Turkey.
Demopulos
C M
CM
Moore
C M
CM
Renshaw
P F
PF
Sachs
G S
GS
D000293:Adolescent; D000328:Adult; D018692:Antimanic Agents / Q000494:pharmacology*; D001921:Brain / Q000378:metabolism*; D005260:Female; D006801:Humans; D007294:Inositol / Q000378:metabolism; D016651:Lithium Carbonate / Q000494:pharmacology*; D008137:Longitudinal Studies; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010716:Phosphatidylinositols / Q000378:metabolism*; D011522:Protons
D018692:Antimanic Agents; D010716:Phosphatidylinositols; D011522:Protons; D016651:Lithium Carbonate; D007294:Inositol