Neonatal alcohol-induced region-dependent changes in rat brain neurochemistry measured by high-resolution magnetic resonance spectroscopy.
BACKGROUND
Maternal drinking during pregnancy can lead to a range of deleterious outcomes in the developing offspring that have been collectively termed fetal alcohol spectrum disorders (FASDs). There is interest and recognized value in using non-invasive neuroimaging techniques such as magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) to characterize, respectively, structural and biochemical alterations in individuals with FASDs. To date, however, results with MRS have been inconsistent regarding the degree and/or nature of abnormalities.


METHODS
High-resolution magic angle spinning (HR-MAS) proton ((1)H) MRS is an ex vivo neuroimaging technique that can acquire spectra in small punches of intact tissue, providing clinically relevant neurochemical information about discrete brain regions. In this study, HR-MAS (1)H MRS was used to examine regional neurochemistry in frontal cortex, striatum, hippocampus, and cerebellum of young rats previously exposed to ethanol as neonates. Key neurochemicals of interest included N-acetyl-aspartate (NAA), glutamate, GABA, glutamine, creatine, choline and myo-inositol.


RESULTS
Daily neonatal alcohol exposure from postnatal day 4 (PN4) through PN9 significantly reduced levels of NAA and taurine in the cerebellum and striatum, and induced sex-dependent reductions in cerebellar glutamate when measured on PN16. In addition, myo-inositol was significantly increased in cerebellum. The frontal cortex and hippocampus were virtually unaffected by this neonatal alcohol exposure.


CONCLUSION
Results of this research may have implications for understanding the underlying neurobiology associated with FASDs and aid in testing treatments in the future. Ongoing studies are assessing the developmental persistence of and/or maturational recovery from these changes.