p -Hydroxyphenylacetic Acid Concentration in the CSF of Patients with Neurological and Psychiatric Disorders

In recent years substantial evidence suggesting that p-tyramine (p-TA) acts as a neurotransmitter or neuromodulator in the brain has been presented (Boulton, 1978; Boulton and Juorio, 1979; Juorio and Jones, 1981). Although the physiological roles of this amine in the central nervous system (CNS) are as yet unknown, it has been claimed that p-TA may be involved in the etiology of certain mental disorders (Boulton and Juorio, 1979; Boulton, 1980). However, there is little clinical evidence for this proposal. p-Hydroxyphenylacetic aid (p-HPAA), a major metabolite of p-TA in the brain (McQuade et al., 1981), has been detected and quantitated in the cerebrospinal fluid (CSF)(Karoum et al., 1975; 1977), but a comparison of p-HPAA concentrations in the CSF of patients with various CNS disorders has not yet been made. We have recently developed a sensitive high-performance liquid chromatographic (HPLC) method for the determination of p-HPAA in CSF (Kobayashi et al., 1982). In this communication we describe CSF levels of p-HPAA in patients with various neurological and psychiatric disorders with special reference to schizophrenia.