The effect of lumbar puncture stress on dopamine and serotonin metabolites in human cerebrospinal fluid.

In order to examine concentrations of cerebrospinal fluid (CSF) neurochemicals, the technique of lumbar puncture is typically used. However, the effect of the intrinsic stress of undergoing a lumbar puncture on CSF monoamine concentrations in humans has not yet been established. We used lumbar puncture followed 3 h later by continuous CSF sampling to examine the effect of lumbar puncture on levels of the dopamine and serotonin metabolites homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), respectively. Additionally, we examined the effect of lumbar puncture on the CSF HVA to 5-HIAA ratio. Immediately post lumbar puncture, CSF concentrations of HVA and 5-HIAA were, respectively, only 51 and 54% of the mean levels detected hours later. However, the HVA to 5-HIAA ratio remained stable during lumbar puncture. While HVA and 5-HIAA levels in CSF obtained via lumbar puncture reflect highly variable responses to the stress of the procedure, the ratio of these metabolites is unaffected.