Plasma 3-methoxy-4-hydroxyphenylglycol changes associated with clinical state and schizophrenic subtype

In a study of 14 drug-free schizophrenic patients and 22 healthy control subjects, the plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) level appeared to be altered by changes in clinical state. Repeated sampling in schizophrenic patients showed that plasma MHPG values were elevated in high-psychosis phases in comparison with metabolite levels at times of lower psychosis. There was a nonsignificant trend toward higher MHPG levels in paranoid schizophrenic patients in comparison with patients who had undifferentiated schizophrenia. Paranoid schizophrenic patients had significantly elevated plasma MHPG levels in comparison with previously studied healthy controls. These findings suggested that alterations in the plasma MHPG level may reflect psychosis-related changes in norepinephrine function in schizophrenia.