Schneider's first-rank symptoms of schizophrenia. An association with increased growth hormone response to apomorphine.

Growth hormone and prolactin (PRL) responses to 0.75 mg of apomorphine hydrochloride were measured in 19 newly admitted psychotic patients who had been untreated by neuroleptic or antidepressant drugs for at least nine months. We compared hormonal responses between subgroups of patients who were distinguished using the diagnostic criteria of Feighner et al and Spitzer et al, and by the presence or absence of Schneider's first-rank symptoms of schizophrenia. We included nine healthy subjects who were matched by age and sex with the schizophrenic patients. Growth hormone responses to apomorphine were greater in patients with Schneider's first-rank symptoms than in those without first-rank symptoms, and were also greater than in control subjects. Suppression of plasma PRL was also greater in schizophrenic patients than in control subjects. These results support the dopamine hypothesis of schizophrenia.