Studies on concentrations of NA and HVA and activity of DBH in the serum from schizophrenic patients, first-degree relatives and normal subjects.

The serum noradrenaline (NA), homovanillic acid (HVA) and dopamine beta-hydroxylase (DBH) have been examined in neuroleptic-free and -treated patients, healthy first-degree relatives of the patients and normal subjects. Analysis of variance (ANOVA) revealed significant differences in the concentrations of serum NA(F = 2.91, p < 0.05) and HVA (F = 3.58, p < 0.05), and in the activity of serum DBH (F = 2.77, p < 0.05) among the four groups. The serum NA was significantly higher in neuroleptic-free patients (475 +/- 220 pg/ml, n = 18), than in healthy first-degree relatives (343 +/- 189 pg/ml, n = 37, p < 0.05) or in normal subjects (354 +/- 111 pg/ml, n = 17, p < 0.05), and it also was significantly higher in neuroleptic-treated patients (442 +/- 223 pg/ml, n = 58) than in healthy first-degree relatives (p < 0.05) or in normal subjects (p < 0.05). There was a trend towards high serum HVA in neuroleptic-free patients (11.3 +/- 6.3 ng/ml, n = 17) compared with the other three groups. The serum DBH activity was high in neuroleptic-free patients (31.2 +/- 15.6 nmol/min/ml, n = 17), and significantly in comparison with those treated with neuroleptic drugs (21.6 +/- 10.9 nmol/min/ml, n = 56, p < 0.05). There was a significant negative correlation between HVA concentration and DBH activity in the serum from neuroleptic-free patients (r = -0.64, n = 16, p < 0.01), and there appeared to be three subgroups with alterations of serum DBH activity and HVA concentration.(ABSTRACT TRUNCATED AT 250 WORDS)