Posted by Elroy on June 21, 2005, at 18:51:40
In reply to Re: HPA Axis Anti-Cortisol Therapy - MORE INFO 5, posted by Elroy on June 21, 2005, at 18:46:08
Misc Info:
Holsboer, F. (2003). "Corticotropin-releasing hormone modulators and depression." Curr Opin Investig Drugs 4(1): 46-50.
Basic and clinical studies demonstrate that the central corticotropin-releasing hormone (CRH) circuits are overactive among depressives, a phenomenon frequently reflected by enhanced cortisol and corticotropin levels in the peripheral blood of these patients. Behavioral pharmacology provided evidence that CRH overexpression accounts for many signs and symptoms characteristic of depression. CRH-type 1 receptors (CRHR), were identified as responsible for conveying the CRH signal into cellular circuitries, thereby inducing depression-related symptoms. In order to decrease CRH signaling, many pharmaceutical companies have developed small molecules that after oral ingestion, penetrate the blood-brain barrier and selectively bind at CRHR1 with high affinity. These compounds have been tested in animal models and patients with major depression. One of these compounds, R-121919 (Neurocrine Biosciences Inc), ameliorated depressive symptomatology without unwanted endocrine side effects or other adverse effects. While clinical trials of R-121919 have been discontinued after phase IIa studies, a number of other CRHR1 antagonists are being developed, and hopefully this advance will ultimately lead to a favorable alternative to currently available antidepressant drugs.
Parker, K. J., A. F. Schatzberg, et al. (2003). "Neuroendocrine aspects of hypercortisolism in major depression." Horm Behav 43(1): 60-6.
A consistent finding in biological psychiatry is that hypothalamic-pituitary-adrenal (HPA) axis physiology is altered in humans with major depression. These findings include hypersecretion of cortisol at baseline and on the dexamethasone suppression test. In this review, we present a process-oriented model for HPA axis regulation in major depression. Specifically, we suggest that acute depressions are characterized by hypersecretion of hypothalamic corticotropin-releasing factor, pituitary adrenocorticotropic hormone (ACTH), and adrenal cortisol. In chronic depressions, however, enhanced adrenal responsiveness to ACTH and glucocorticoid negative feedback work in complementary fashion so that cortisol levels remain elevated while ACTH levels are reduced. In considering the evidence for hypercortisolism in humans, studies of nonhuman primates are presented and their utility and limitations as comparative models of human depression are discussed.
Rothschild, A. J. (2003). "Challenges in the treatment of depression with psychotic features." Biol Psychiatry 53(8): 680-90.
Major depression with psychotic features (MDpsy), a disorder with considerable morbidity and mortality, is more common than is generally realized and is a most difficult form of depression to treat. Patients with MDpsy exhibit more frequent relapses and recurrences and have increased use of services, greater disability, and a poorer clinical course when compared with nonpsychotically depressed patients. Patients with MDpsy demonstrate distinct biological abnormalities in studies of the hypothalamic-pituitary-adrenal (HPA) axis, dopaminergic activity, enzyme studies, brain imaging, electroencephalogram sleep profiles, and measures of serotonergic function when compared with nonpsychotic depression. The social and occupational impairment in MDpsy has been hypothesized to be secondary to subtle cognitive deficits caused by the higher cortisol levels frequently observed in MDpsy patients. Several studies support a relationship between bipolar disorder and MDpsy, particularly in young-onset MDpsy. The most efficacious treatments for MDpsy include the combination of an antidepressant and an antipsychotic, amoxapine, or electroconvulsive therapy. Atypical antipsychotic medications may have particular relevance for the treatment of MDpsy because of the potential for reduced risk of extrapyramidal side effects and tardive dyskinesia, as well as antipsychotic and possibly antidepressant qualities. Based on the observations that MDpsy patients exhibit marked dysregulation of the HPA axis and elevated cortisol levels, several antiglucocorticoid strategies have been employed to treat MDpsy patients. Many questions regarding the acute and long-term treatment of MDpsy remain for future studies to address.
Elroy
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thread:515432
URL: http://www.dr-bob.org/babble/20050617/msgs/516770.html