UMLS:C0011570 - FACTA Search

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Query: UMLS:C0011570 (depression)
172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report here a study of the effects of alprazolam on in vivo pituitary-adrenal function in jacketed nonrestrained nonhuman primates and on in vitro CRH release from rat hypothalami and ACTH release from rat dispersed anterior pituicytes. We undertook this study because alprazolam is the only benzodiazepine effective in treating both major depressive and anxiety disorders, and recent data suggest that the hypercortisolism of major depression reflects hypersecretion of CRH. Moreover, the intracerebroventricular administration of CRH can reproduce many of the components of the symptom complex of major depression, including not only hypercortisolism, but also hypothalamic hypogonadism, decreased libido, anorexia, and intense anxiety. As a comparison, we also assessed the effects of diazepam on in vitro CRH release, because in contrast to alprazolam, diazepam is effective in anxiety states but not in depression. Alprazolam (0.01-0.3 mg/kg, iv) produced a dose-dependent inhibition of both plasma ACTH and cortisol secretion in non-restrained adult male rhesus monkeys. Our in vitro studies showed that alprazolam significantly inhibited serotonin (5HT)-induced CRH release in a dose-dependent fashion (10(-10)-10(-5) M). Diazepam also inhibited 5HT-induced CRH release, but was 40 times less potent than alprazolam. Alprazolam was ineffective in blocking basal or CRH-induced ACTH release from rat dispersed anterior pituicytes, suggesting that its in vivo effects are through inhibition of CRH secretion. As expected, the inactive benzodiazepine ligand Ro 15-1788 inhibited the effects of alprazolam on 5HT-induced CRH release, but this occurred only at doses below 10(-7) M. Interestingly, when incubated alone in higher doses with our rat hypothalamic organ culture, Ro 15-1788, like alprazolam, produced a dose-dependent inhibition of 5HT-induced CRH release (10(-7)-10(-5) M), suggesting an agonistic action of Ro 15-1788 at the benzodiazepine receptor at higher concentrations. We conclude that alprazolam is capable of suppressing the primate pituitary-adrenal axis, and that this suppression most likely reflects suppression of the CRH neuron rather than of the pituitary corticotroph cell. We speculate that the enhanced capacity of alprazolam to suppress the CRH neuron relative to other benzodiazepines may contribute to its unique efficacy among this class of drugs in the treatment of major depression. The capacity of Ro 15-1788 to reverse alprazolam-induced suppression of the CRH neuron indicates that the effects of alprazolam are mediated at least in part via its interaction with the benzodiazepine component of the gamma-aminobutyric acidA macromolecular complex.
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PMID:In vitro and in vivo effects of the triazolobenzodiazepine alprazolam on hypothalamic-pituitary-adrenal function: pharmacological and clinical implications. 215 87

Patients with primary affective disorders, such as melancholic depression and anorexia nervosa, frequently have a hyperactive hypothalamic-pituitary-adrenal (HPA) axis, characterized by hypersecretion of CRH and a blunted ACTH response to exogenous CRH. Premenstrual syndrome (PMS) is a luteal phase dysphoric disorder characterized by primarily affective and behavioral disturbances. HPA axis function was compared in PMS patients and control women, respectively, diagnosed by DSM3-R criteria or found to have no current psychiatric disorders, determined by the Schedule for Affective Disorders and Schizophrenia-Lifetime Interview. Urinary free cortisol excretion was the same in PMS and normal women, and no differences in urinary free cortisol excretion between the follicular and luteal phases occurred in either group. Two HPA axis abnormalities, however, were noted when PMS patients were compared to normal women. First, basal evening cortisol concentrations in plasma were significantly decreased, while the time-integrated response of plasma cortisol to ovine (o) CRH was significantly increased. Second, the negative correlation between time-integrated plasma ACTH and cortisol responses to oCRH and basal luteal progesterone concentrations present in normal control women was not seen in the PMS patients. These changes in basal and oCRH-stimulated plasma cortisol levels in association with normal urinary free cortisol excretion suggest that women with PMS might have transient or episodic disturbances of their HPA axis, which appear adequately corrected by this system's servomechanisms. This probably explains the maintenance of regular menstrual cycles in PMS patients, which contrasts with the irregular menses observed in patients with depression, anorexia nervosa, or women who participate in chronic strenuous exercise.
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PMID:Hypothalamic-pituitary-adrenal function in patients with the premenstrual syndrome. 217 72

Since the discovery of CRH in 1981, several investigators have reported abnormalities of the hypothalamic-pituitary-adrenal (HPA) system in response to direct stimulation of the corticotroph cells in patients with psychiatric disorders. To further explore HPA system integrity in major depressive disorders, 13 drug-free patients and normal subjects matched for age, sex, ovarian status, and body weight received 100 micrograms synthetic human CRH as an iv bolus dose. Compared to that in the normal subjects, in the depressed patients a significant attenuation of the net ACTH release after CRH administration (772 +/- 597 vs. 263 +/- 286 pmol/min.L; P less than 0.02) was observed, while beta-endorphin and cortisol responses did not differ significantly between the groups. The magnitudes of ACTH and cortisol release were negatively correlated in the patient group only (r = -0.67; P less than 0.01). Thus, the blunted ACTH response to CRH in depression might be related to hypercortisolemia, while the implications of the apparent dissociation of ACTH and beta-endorphin after CRH administration still remain unclear. Our data support the hypothesis that the hyperactivity of the HPA system in depression most likely is a consequence of CRH hypersecretion, the origin of which may be explained by abnormal central glucocorticoid receptor or neurotransmitter regulation.
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PMID:Blunted adrenocorticotropin but normal beta-endorphin release after human corticotropin-releasing hormone administration in depression. 254 28

We compared the baseline cortisol secretory pattern and ACTH and cortisol responses to hCRH (100 micrograms) in eight patients acutely withdrawn from ethanol and 12 patients who abstained from ethanol for two to six weeks. Acute withdrawal from ethanol was characterized by elevated baseline cortisol and blunted ACTH release after hCRH, while medium-term abstention was associated with normalized cortisol secretion but persistence of decreased ACTH output following stimulation. These findings support an altered corticotrophic CRH receptor function in detoxified sober alcoholics. The pathophysiology underlying the blunted ACTH response to hCRH in medium-term ethanol abstention appears to be different from that in acute alcohol withdrawal and hypercortisolemic depression.
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PMID:Human CRH stimulation response during acute withdrawal and after medium-term abstention from alcohol abuse. 256 Feb 22

To explore the integrity of the hypothalamic-pituitary-adrenal (HPA) system in major depressive disorder, 12 patients and normal controls matched for sex, age, and body weight received 100 micrograms synthetic human corticotropin-releasing hormone (hCRH) as an i.v. bolus dose. Compared to controls, depressed patients showed an elevation in baseline cortisol and a significant attenuation of net adrenocorticotropin (ACTH) responses, while cortisol secretion in response to hCRH was normal. These abnormalities in HPA axis function and apparent discordances in the interrelationships of ACTH and cortisol baseline and net stimulation responses between depressed patients and normal controls indicate, at least in part, a derangement of the glucocorticoid-dependent negative feedback circuitry and support the hypothesis that HPA hyperactivity in depression involves neurotransmitter-mediated hypothalamic hypersecretion of CRH.
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PMID:Corticotropin and cortisol response to human CRH as a probe for HPA system integrity in major depressive disorder. 283 59

The current concept that blunted adrenocorticotropic hormone (ACTH) response to human corticotropin-releasing-hormone (h-CRH) in depression is primarily determined by elevated circulating plasma cortisol levels is still unproven. We tested this hypothesis by comparing ACTH release following intravenous administration of 100 micrograms h-CRH in 10 normal controls and in 21 inpatients with a major depressive episode. Eleven of these depressed patients were pretreated with an oral dose of 2 g metyrapone, which inhibits cortisol biosynthesis by blocking C-11 beta-steroid-hydroxylase. This intervention deprives the entire system of cortisol, which is the major feedback signal for the regulation of ACTH secretion at various pituitary and limbic sites. ACTH responses, assessed as areas-under-time-course-curves, were: in normal controls, 6.8 +/- 2.4 (SD) pg/ml/min x 10(3); in unmedicated patients, 2.6 +/- 1.1 pg/ml/min x 10(3); and in metyrapone pretreated patients, 9.0 +/- 6.7 pg/ml/min x 10(3). Thus, ACTH release in unmedicated depressed patients was significantly (p less than 0.001, Mann-Whitney U-test) blunted when compared with normal controls. In contrast, this blunting was completely avoided after metyrapone pretreatment, which resulted in net ACTH responses that were indistinguishable from those of the controls.
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PMID:Blunting of ACTH response to human CRH in depressed patients is avoided by metyrapone pretreatment. 285 10

1. The 41 amino acid peptide human corticotropin releasing hormone (h-CRH) and its ovine analogue o-CRH are regulators of proopiomelanocortin (POMC) derived neuropeptides and neurosteroids of the limbic-hypothalamic-pituitary-adrenocortical (LHPA) axis such as beta-endorphin, corticotropin (ACTH) and corticosteroids modulating concomitantly hormonal and behavioral systems in animal and man, e.g. adaptation to stress. 2. Challenge tests employing h-CRH stimulation with or without different kinds of pretreatment in affective disorders, alcoholism, and panic disorder demonstrate LHPA alterations that are induced by dysregulations in the limbic area. In depression, the enhanced secretory activity of pituitary corticotrophs or altered feedback regulation is compatible with endogenous CRH hypersecretion followed by enhanced production of proopiomelanocortin whose fragments activate synthesis and release of adrenal corticosteroids. These effects are accompanied by development of a functional hyperplasia of the adrenocortex and/or down-regulation of pituitary CRH-receptors and/or reduced negative feed back capacity of limbic glucocorticoid receptor containing neurones particularly in the hippocampus. Similar disturbances are found in hypercortisolemic patients withdrawn from alcohol and are less pronounced in patients with panic disorder. 3. Repetitive h-CRH administration to normal controls induces sleep-EEG and neuroendocrine effects resembling those in depression. 4. Adrenocortical hormones act back on neurotransmitter/receptor sites of brain systems relevant for neuropharmacoloy (e.g. GABA receptor activity in anxiety disorders and affective disorders). 5. The neuroendocrine approach to the LHPA axis is of value to uncover several aspects of pathology underlying various psychiatric diseases.
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PMID:Human corticotropin releasing hormone: clinical studies in patients with affective disorders, alcoholism, panic disorder and in normal controls. 285 97

Corticotropin releasing factor (CRF) is a newly sequenced peptide first isolated from sheep hypothalami and thought to be an important modulator of both the pituitary-adrenal axis and the sympathetic nervous system. We administered intravenous, intramuscular, and intracerebroventricular CRH to non-human primates and measured plasma ACTH, beta endorphin, cortisol, GH and PRL responses to CRF. In addition, we determined the pharmacokinetic properties of I125 in these primates. We administered CRF as an intravenous bolus or as a continuous infusion to normal volunteers and as an intravenous bolus to patients with disorders of the hypothalamic-pituitary-adrenal axis, such as Cushing's syndrome and adrenal insufficiency, and patients with endogenous depression and mild hypercortisolism, and assessed their plasma ACTH, cortisol, GH and PRL responses. In addition, we determined the pharmacokinetic properties of CRF in man by measuring CRF immunoreactivity in plasma. CRF given intravenously to primates or man is a slowly metabolized, long-acting, secretagogue of ACTH, beta-endorphin and cortisol. When given intracerebroventricularly to primates it stimulates the hypothalamic-pituitary-adrenal axis without escaping into the plasma and it is actively cleared in the CNS. It does not cross the blood brain barrier appreciably when given intravenously. CRF given to primates and men as an intravenous continuous infusion has only mild ACTH stimulating effects and this may be due to an intact cortisol negative feedback system. Finally, CRF causes characteristic plasma hormone responses in patients with Cushing's disease, adrenal insufficiency and depression.
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PMID:Corticotropin releasing factor: basic studies and clinical applications. 299 71

Twenty-two subjects (11 patients with major endogenous depression and 11 controls) received an intravenous test dose of 100 micrograms human corticotropin-releasing hormone (h-CRH). Corticotropin (ACTH), but not cortisol, responses were blunted in depressives. Basal cortisol secretion was higher in depressives than in controls and was negatively correlated to the corticotropin response following h-CRH. This finding indicates the integrity of the glucocorticoid-dependent negative feedback regulation in depression and supports the view that hypercortisolism in depression is primarily due to a suprapituitary disturbance. Comparison of ACTH responses after h-CRH with thyrotropin (TSH) output following thyrotropin-releasing hormone (TRH) revealed a positive correlation (r = 0.65, p less than 0.001). The concordance between ACTH and TSH responses after specific challenges suggests that regulation of both systems is at least in part under a common control.
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PMID:Human corticotropin-releasing hormone in depression--correlation with thyrotropin secretion following thyrotropin-releasing hormone. 301 Nov 29

CRH is a 41 amino acid peptide first isolated from ovine and subsequently from rat and human hypothalami. We have conducted a series of clinical studies with oCRH and hCRH in volunteers and patients with various disorders of hypothalamic-pituitary-adrenal function. In volunteers, it was demonstrated that hCRH administration produced ACTH and cortisol responses which closely mimic naturalistically occurring secretory episodes. This data, as well as the demonstration that pulsatile hCRH can reestablish normal ACTH and cortisol secretion in patients with hypothalamic CRH deficiency, strongly argue that CRH is of physiological relevance to the human pituitary-adrenal axis. However, since the ACTH response to an insulin tolerance test is greater than the maximal ACTH response to CRH, other factors such as vasopressin may be relevant to stress-induced ACTH secretion in man. Following the demonstration that CRH seems to be of physiological relevance to human subjects, a CRH stimulation test was developed based on pharmacokinetic and dose response studies with oCRH and hCRH. Based on these data, which revealed that oCRH functions as a long-acting analogue of hCRH, and the demonstration that hormonal responses to CRH are greatest in the evening, patient groups with abnormalities of the hypothalamic-pituitary-adrenal axis were tested with intravenous oCRH with a dose of 1 micrograms/kg given at 2000 hours. This CRH stimulation test has proved helpful in clarifying the pathophysiology of hypercortisolism in a variety of psychiatric disorders characterized by this endocrine abnormality. Thus, blunted ACTH responses in hypercortisolemic patients with depression, anorexia nervosa, and panic anxiety disorder indicate normality of the pituitary corticotroph in these patient subgroups. These data, along with the finding that a continuous infusion of CRH to normal volunteers, reproduces the pattern and magnitude of hypercortisolism in depression and anorexia nervosa, suggest that the hypercortisolism in these disorders represents a defect at or above the hypothalamus resulting in the hypersecretion of CRH. This hypothesis is particularly intriguing in light of the demonstration that CRH administration to experimental animals produces many of the physiological and behavioral responses classically associated with depression and anorexia nervosa, including hypercortisolism, hypothalamic hypogonadism, and decreases in libido and appetite. The CRH stimulation test has also helped to resolve one of the oldest endocrinological dilemmas, namely whether the hypercortisolism of depression and Cushing's disease share a common or dissimilar pathophysiological basis.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Corticotropin releasing hormone: relevance to normal physiology and to the pathophysiology and differential diagnosis of hypercortisolism and adrenal insufficiency. 303 86

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