Abstract #1480

Xiang Y, Gao H, Zhu H, Sun N, Ma Y, Liu M, Lei H

The effects of chronic morphine treatment and subsequent withdrawal on the metabolism of glutamate (Glu)-GABA neurotransmitter systems in the prefrontal cortex (PFC) of rats were studied by ex vivo high resolution 1H nuclear magnetic resonance spectroscopy. It is shown that chronic morphine treatment induces a progressive increase in GABA, and concurrent decreases in Glu and Glu/GABA ratio. Such changes are reversible during subsequent withdrawal, and might be manifestations of adaptive alterations of the neurotransmitter systems in response to repeated morphine exposures. The results are also consistent with the previous results showing that the PFC activities are reduced in drug addicts.