Biological psychiatry
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Biological psychiatry · May 2009
Pattern of intake and drug craving predict the development of cocaine addiction-like behavior in rats.
Clinical observations suggest that cocaine addiction often emerges with new patterns of use. Whether these changes are a cause of addiction or its consequence is unknown. We investigated whether the development of an addiction-like behavior in the rat is associated with the pattern of cocaine intake and with cocaine craving, a major feature of cocaine addiction. ⋯ Our results identify key predictors of cocaine addiction-intensified pattern of drug use and high drug-induced craving-that may help in the identification of subjects at risk for subsequent development of severe cocaine addiction.
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Biological psychiatry · May 2009
Comparative StudyAmino acid neurotransmitters assessed by proton magnetic resonance spectroscopy: relationship to treatment resistance in major depressive disorder.
Significant alterations in gamma-aminobutyric acid (GABA) and glutamate levels have been previously reported in major depressive disorder (MDD); however, no studies to date have investigated associations between these amino acid neurotransmitters and treatment resistance. ⋯ Our findings corroborate previous reports of decreased GABA in MDD and provide initial evidence for a distinct neuronal amino acid profile in patients who have failed to respond to several standard antidepressants, possibly indicative of abnormal glutamate/glutamine/GABA cycling. Given interest in novel antidepressant mechanisms in TRD that selectively target amino acid neurotransmitter function, the translational relevance of these findings awaits further study.