RT Journal Article SR Electronic T1 Phenylacetic acid in human body fluids: high correlation between plasma and cerebrospinal fluid concentration values. JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP 366 OP 368 DO 10.1136/jnnp.45.4.366 VO 45 IS 4 A1 Sandler, M A1 Ruthven, C R A1 Goodwin, B L A1 Lees, A A1 Stern, G M YR 1982 UL http://jnnp.bmj.com/content/45/4/366.abstract AB In a group of six Parkinsonian patients and 13 "controls" with non-Parkinsonian neurological disease, there was a high correlation between both free and conjugated phenylacetic acid concentrations in plasma and cerebrospinal fluid taken at about the same time. This compound is the major metabolite of phenylethylamine, the production of which may be disturbed in a number of neuropsychiatric illnesses. Thus plasma measurements might be employed clinically to provide an estimate of central changes in phenylethylamine economy. A small but significantly higher proportion of conjugated phenylacetic acid was present in the plasma (but not cerebrospinal fluid) of Parkinsonians compared with controls.