Effects of bupropion SR on anterior paralimbic function during waking and REM sleep in depression: preliminary findings using [F-18]-FDG PET

This study sought to clarify the effects of bupropion SR on anterior parali mbic function in depressed patients by studying changes in the activation o f these structures from waking to REM sleep both before and after treatment . Twelve depressed patients underwent concurrent EEG sleep studies and [F-1 8]fluoro-2-deoxy-D-glucose ([F-18]-FDG) positron emission tomography (PET) scans during waking and during their second REM period of sleep before and after treatment with bupropion SR. Nine subjects completed pre- and post-tr eatment waking PET studies. Five subjects completed pre- and post-treatment waking and REM sleep PET studies. Bupropion SR treatment did not suppress electrophysiologic measures of REM sleep, nor did it alter an indirect meas ure of global metabolism during either waking or REM sleep. Bupropion SR tr eatment reversed the previously observed deficit in anterior cingulate, med ial prefrontal cortex and right anterior insula activation from waking to R EM sleep. In secondary analyses, this effect was related to a reduction in waking relative metabolism in these structures following treatment in the a bsence of a significant effect on REM sleep relative metabolism. The implic ations of these findings for the relative importance of anterior paralimbic function in REM sleep in depression and for the differential effects of an ti-depressant treatment on brain function during waking vs. REM sleep are d iscussed. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.