In vivo influences on cerebrospinal fluid amino acid levels.

The concentration of 19 amino acids and ethanolamine in two independent groups (n = 36, n = 19) of normal human cerebrospinal fluid (CSF) samples were measured by high performance liquid chromatography. Age, sex, time of lumbar puncture, position during lumbar puncture, protein and glucose content of the CSF were monitored and the influence of these parameters on CSF amino acid levels was determined. Hypotheses formulated after observing measurements from the first group of CSF samples were tested against the second group of CSF samples using conservative statistics. The main finding was a positive correlation between CSF glucose and CSF glutamate levels.