Study Report
Reference
| Citation | Aihara, 2007 PubMed |
| Full Info | Aihara, M., Ida, I., Yuuki, N., Oshima, A., Kumano, H., Takahashi, K., Fukuda, M., Oriuchi, N., Endo, K., Matsuda, H. et al. (2007) HPA axis dysfunction in unmedicated major depressive disorder and its normalization by pharmacotherapy correlates with alteration of neural activity in prefrontal cortex and limbic/paralimbic regions. Psychiatry Res, 155, 245-256.
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Study
| Hypothesis or Background |
Dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis is one of the most prominent neurobiological findings in major depressive disorder (MDD). The relationship of regional brain metabolism to HPA axis dysfunction in depressed patients, however, is still unclear.
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| Sample Information | 24 antidepressant-free patients with MDD |
|---|
| Method Detail | In this study, to examine the clinical pharmacotherapeutic effects on HPA axis function and brain metabolism in MDD patients, we performed the combined dexamethasone (DEX)/corticotropin-releasing hormone (CRH) test on 24 antidepressant-free patients with MDD a few days after positron emission tomography (PET) with a radiotracer, [(18)F]-fluorodeoxyglucose (FDG). Moreover, 10 patients who responded to pharmacotherapy were re-tested. |
| Method Keywords | dose administration; positron emission tomography (PET) |
| Result | 75% of unmedicated MDD patients exhibited a heightened cortisol response to the DEX/CRH test, and thus were defined as non-suppressors. Non-suppressors showed a marked hypometabolism in the medial prefrontal cortex as compared with suppressors. After successful pharmacotherapy, enhanced cortisol responsiveness normalized. Prior to treatment of the unmedicated MDD, a significant hypometabolism in various frontal regions and a significant hypermetabolism in the right hippocampus and parahippocampal gyrus were observed compared with controls. Metabolic activity in treatment responders showed a normalizing pattern in almost all the areas that had been characterized by metabolic abnormality at baseline except for the medial prefrontal cortex. |
| Conclusions | These results indicate that depressed patients remitted with antidepressant treatment were accompanied by resolution of HPA dysregulation and alteration of regional glucose metabolism in the prefrontal cortical, limbic and paralimbic regions. |
Relationships reported by
Aihara, 2007
| Component A Approved Name (Name in Paper) |
Component A Type |
Component B Approved Name (Name in Paper) |
Component B Type |
Statistical Result |
Relationship Description |
Result Category (Positive/Negative)) |
|
MDD
|
syndrome |
Hydrocortisone (cortisol) |
molecule |
|
75% of unmedicated MDD patients exhibited a heightened cortisol response to the combined dexamethasone (DEX)/corticotropin-releasing hormone (CRH) test. |
Positive
|
|
MDD
|
syndrome |
right hippocampus (right hippocampus) |
brain morphology and function |
|
Prior to treatment of the unmedicated MDD, a significant hypermetabolism in the right hippocampus were observed compared with controls. |
Positive
|
|
MDD
|
syndrome |
Glucose (glucose) |
molecule |
|
These results indicate that depressed patients remitted with antidepressant treatment were accompanied by resolution of HPA dysregulation and alteration of regional glucose metabolism in the prefrontal cortical, limbic and paralimbic regions. |
Positive
|
|
MDD
|
syndrome |
Hypothalamic-pituitary-adrenal axis (HPA) |
neurobiological system |
|
These results indicate that depressed patients remitted with antidepressant treatment were accompanied by resolution of HPA dysregulation and alteration of regional glucose metabolism in the prefrontal cortical, limbic and paralimbic regions. |
Positive
|
|
MDD
|
syndrome |
Frontal Lobe (frontal regions) |
brain morphology and function |
|
Prior to treatment of the unmedicated MDD, a significant hypometabolism in various frontal regions were observed compared with controls. |
Positive
|
|
MDD
|
syndrome |
Parahippocampal gyrus (parahippocampal gyrus) |
brain morphology and function |
|
Prior to treatment of the unmedicated MDD, a significant hypermetabolism in the parahippocampal gyrus were observed compared with controls. |
Positive
|
|
Hypothalamic-pituitary-adrenal axis (HPA)
|
neurobiological system |
medial prefrontal cortex (MPFC) (medial prefrontal cortex) |
brain morphology and function |
|
75% of unmedicated MDD patients exhibited a heightened cortisol response to the combined dexamethasone (DEX)/corticotropin-releasing hormone (CRH) test, and thus were defined as non-suppressors. Non-suppressors showed a marked hypometabolism in the medial prefrontal cortex as compared with suppressors. After successful pharmacotherapy, enhanced cortisol responsiveness normalized. |
Positive
|
