Dopamine beta hydroxylase (DBH) plasma activity in childhood mental disorders.

BACKGROUND: Developmental study of dopaminergic and noradrenergic systems in child psychiatric disorders are rare. DBH activity is one of noradrenergic biochemical marker that is correlate in psychiatry to clinical and genetic data. OBJECTIVES: The main aim of the present study was to measure DBH activity at the onset of acute schizophrenia and depressive disorder in children and adolescents without pharmacological treatment and to compare these values with DBH activity in healthy controls. The authors also investigated untreated ADHD children. METHODS: We examined 42 control healthy children, 15 children non-treated with acute schizophrenia, 15 non-treated children with acute depressive disorders and 30 non-treated ADHD children, all in age 7-14. Plasma DBH level was provided by Nagatsu (1972; 1974). Depressed children were reexamined after clinical remission. RESULTS: DBH activity is statistically significantly decreased in non-treated depressive disorder and ADHD in children and adolescents. DBH activity is normalised during antidepressant therapy in child depression. Child schizophrenia patients present with normal DBH activity. CONCLUSION: These results are similar to the results that have been observed in adult patients with schizophrenia and depression and in previous studies of DBH activity in children with ADHD. These results also indicate hypoactivity of the noradrenergic system in children with ADHD and depression.

Some ADHD polymorphisms (in genes DAT1, DRD2, DRD3, DBH, 5-HTT) in case-control study of 100 subjects 6-10 age.

BACKGROUND: Pharmacological approach is the most effective way of treatment of ADHD and its early application prevents from the progress of secondary disorders. The study on present neurotransmitter systems in pathology of ADHD can be helpful in selecting appropriate drug, since there are used various substances with different mechanisms of functioning in treatment of the hyperkinetic syndrome. METHOD: Within our study there were selected the genes of dopaminergic (DRD2, DRD3, DAT1), noradrenergic (DBH) and serotoninergic (5-HTT) systems. With the use of molecular-genetic methods based on association strategy "case-control" there were analysed genes including 11 polymorphisms. The presence of risk alleles was examined in comparison of the sample of 100 ADHD children to a control group of another 100 subjects, who were checked by child psychiatrists and examined with the Conners test in order to exclude eventual cases with ADHD symptoms. RESULTS: Our research suggests the association of some genes with ADHD. It could be concluded: 1) the risk of ADHD is significantly increased in the presence of one risk allele in genes DRD2 (O.R.=7,5), 5-HTT (O.R.=2,7) and DAT1 (O.R.=1,6). 2) The risk of ADHD is significantly increased at homozygotes for risk alleles in genes DRD2 (O.R.=54,8), 5-HTT (O.R.=6,7) and DAT1 (O.R.=6,6). For polymorphisms G444A and C1603T in DBH, which were detected by univariant analysis, haplotype analysis was performed and resulted in conclusion that: 3) the risk of ADHD is significantly increased in the presence of allele DBH +444A as well as in the presence of allele DBH +1603T (O.R.=15).