Shinichiro Nanko — Page 2

PubMed2002

Novel polymorphisms in the promoter region of the neurotrophin-3 gene and their associations with schizophrenia.

Based on the neurodevelopmental hypothesis in the etiology of schizophrenia, neurotrophic factors may be involved in the pathogenesis of the illness. We searched for polymorphisms in the promoter region of the neurotrophin-3 (NTF3) gene by using denaturing high performance liquid chromatography (DHPLC). Six single nucleotide polymorphisms (SNPs) were found. When these polymorphisms were examined for association with schizophrenia, a weakly significant difference was observed in the genotype distribution of the G/- 3004/A polymorphism between 184 schizophrenics and 185 controls (P < 0.05), although no statistically significant association was detected in a family-based sample of 50 trios (schizophrenics and their parents). With respect to the other polymorphisms, there was no significant association with schizophrenia. The G/- 3004/A polymorphism was in linkage disequilibrium with the CA repeat polymorphism in the first intron of the NTF3 gene. When haplotype-based analysis was performed, an increased frequency of the haplotype containing the G(- 3004) and the "A3" ([CA]23) alleles was observed for the schizophrenics compared to controls. Our results suggest that the G(- 3004)-A3 haplotype has a modest effect of giving susceptibility to schizophrenia.

Adult↗

PubMedDate not supplied

Combined DEX/CRH test among Japanese patients with major depression.

There is compelling evidence for an important role of the hypothalamus-pituitary-adrenal (HPA) axis abnormalities in the pathophysiology of major depressive disorder. Growing evidence has suggested that the combined dexamethasone (DEX)/CRH test is much more sensitive than the conventional DEX suppression test in order to detect HPA axis abnormalities. However, little data is currently available on DEX/CRH results for Asian populations, which prompted us to examine the sensitivity of the DEX/CRH test among Japanese subjects with major depression. The DEX/CRH test was administered in 20 inpatients with major depressive episode and 30 healthy controls. Significantly increased cortisol responses were observed for the patients, compared to the controls. There was a substantial difference in the distribution of non-suppressor, intermediate suppressor, and suppressor, which were defined in terms of cortisol response, was observed between the patients and controls (10, 60, and 30% in the patients vs. 0, 27, and 73% in the controls, P<0.01). Responses of ACTH showed a trend in the same direction. Within the depressed patients, individuals with a history of attempted suicide, in particular, tended to have enhanced responses to the DEX/CRH test, compared to those without such a history. Our results confirmed that the DEX/CRH test is a sensitive test to detect HPA axis abnormalities among Japanese patients with major depression. In addition, a possible relationship between suicidal acts and enhanced HPA axis abnormalities was suggested.

Corticotropin-Releasing Hormone↗