Stability of CSF metabolites measured by proton NMR

Analysis of cerebrospinal fluid (CSF) metabolites can provide data regardin g CNS involvement in neurologic and psychiatric illness. However, there is lack of research into the effect of processing and storage of CSF specimens on the levels of metabolites analyzed. CSF specimens from 10 depressed pat ients were analyzed by proton NMR before and after 72 hours exposure to roo m temperature. No effect of exposure was found on myoinositol, glucose, ace tate, and alanine CSF levels and there was a substantial decrease of citrat e (>50%) and increase in lactate, glutamine, creatine, and creatinine level s.