Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pharmacokinetics of amitriptyline (AMI) have been extensively studied, and a large interindividual variability between oral dose and concentration of the drug in plasma has been documented. The aim of this study was twofold: first, to compare AMI kinetics in depressed patients with those of healthy controls and, second, to describe the relationship between AMI levels in plasma and hypothalamic-pituitary-adrenal (HPA) system changes during depression. Thirty-eight patients with a DSM-III-R diagnosis of major depression and 13 healthy control persons received 75 mg of AMI daily for 6 weeks. Levels of AMI and nortriptyline in plasma were determined, and neuroendocrine testing with the combined dexamethasone-suppression/CRH-stimulation test (DST) was done before AMI administration and after weeks 1, 3, and 6 of medication. AMI levels in plasma were significantly higher in the patient group compared with controls during the entire treatment period, whereas nortriptyline levels did not differ between the two groups. Drug levels correlated significantly with age, but gender had no effect on the concentration of the drug in plasma. Twenty-two patients remitted after treatment. There was no difference in drug levels between responders and nonresponders. Fifteen patients were DST nonsuppressors before treatment; 23 patients and all controls suppressed cortisol after dexamethasone. DST suppressors had significantly higher AMI levels in plasma at weeks 3, 5, and 6 compared with DST nonsuppressors. In comparison to patients with high AMI levels in plasma, those with low drug concentration had higher postdexamethasone cortisol and adrenocorticotropic hormone levels and an increased hormone release after additional CRH.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Amitriptyline metabolism in elderly depressed patients and normal controls in relation to hypothalamic-pituitary-adrenal system function. 759 7

Acute and chronic stress as well as a number of psychiatric and neurological disorders are accompanied by profound disturbances of the HPA system. These neuroendocrine alterations act back on the central nervous tissue mainly via corticosteroids-affecting glucocorticoid and mineralocorticoid receptors. The major conclusions drawn from studies probing these receptors in clinical investigations are: (1) In many such conditions central corticosteroid receptors are weakened in their capacity to curtail spontaneous and stress-elevated corticosteroid levels; (2) the combined DEX-CRH test is the best neuroendocrine tool currently available for identifying HPA abnormalities in psychiatric patients; (3) in depression the decreased corticosteroid receptor capacity in transient, and antidepressants act through reinstatement of GR and MR function probably resulting in reduced hypothalamic CRH and AVP production; (4) several neurological disorders such as MS and HIV infection are often accompanied by altered HPA function, which has therapeutic implications; and (5) various corticosteroids, their biosynthetic precursors and their metabolites have differentiable effects on the sleep EEG, which can be attributed to their mode of action; specifically, steroids such as pregnenolone and DHEA most likely are produced in glia cells and act in a paracrine fashion at neurons, thus modifying the sleep EEG in humans in a manner that suggests their potential as memory enhancers.
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PMID:Steroid effects on central neurons and implications for psychiatric and neurological disorders. 782 89

The present study was designed to investigate the clinical efficacy of trimipramine with adjunct sleep deprivation (SD) or bright light (BL) and to evaluate psychometric and neurobiological variables that might be of predictive value for treatment response. We used (1) the combined dexamethasone-corticotropin releasing hormone test (DEX-CRH test) to characterize alterations of the hypothalamic-pituitary-adrenal (HPA) system; (2) polysomnography to evaluate sleep disturbances; and (3) a standardized test battery to assess cognitive psychomotor functions after study initiation and after 5 weeks of treatment. The overall response rate (> or = 50% decrease in score on Hamilton Rating Scale for Depression [HRS]) was 55% (N = 42). The response rate in the group with trimipramine monotherapy (N = 14) was 79%, whereas in the groups with adjunct SD (N = 14) and BL (N = 14), respectively, it was only 43%. All three groups showed significant improvement at the end of the third week of treatment. Neither of the adjunct treatments hastened the onset of antidepressant action as measured by HRS. A significantly higher proportion of nonresponders than responders (p < .05) had HPA dysregulation, disturbed rapid eye movement (REM) sleep (REM latency, REM% first third of night) and decreased non-REM sleep (% stage 2). The non-responders showed significantly more corticotropin (ACTH) secretion after CRH stimulation in the DEX-CRH test than the responders and a less rapid normalization of the neuroendocrine dysregulation (cortisol secretion) (p < .01). In addition, REM latency was significantly shorter in the BL group than in the monotherapy group and estimated duration of illness significantly longer in the SD group than in the monotherapy group. REM latency, percentage of REM sleep during the first third of the total sleep period, percentage of non-REM sleep stage 2 and ACTH release after a DEX-CRH challenge predicted response across all three treatment groups. The neurobiological symptoms were unevenly distributed, among the three groups, thus creating heterogeneity in these measures. This heterogeneity may have contributed to the different treatment response rates as defined by psychopathology (HRS). In contrast, the neuropsychological tests and some of the sleep-EEG investigations revealed different response patterns for different groups: The onset of improvement in simple cognitive functions and in sleep continuity was earlier in the adjunct treatment groups. This study underlines the need for a multidimensional approach including use of neurobiological and neuropsychological measures to identify the therapeutic profiles of different treatment strategies and predictors of outcome.
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PMID:Sleep deprivation and bright light as potential augmenters of antidepressant drug treatment--neurobiological and psychometric assessment of course. 787 17

Desipramine (DMI), a tricyclic antidepressant and norepinephrine (NE) reuptake blocker, is reported to induce ACTH and cortisol release acutely in humans, probably by facilitating central NE neurotransmission. Tricyclic antidepressant therapy, including DMI, normalizes the ACTH and cortisol hypersecretion that often accompanies depression. The mechanism of hypothalamic-pituitary-adrenal (HPA) axis inhibition by DMI in humans is unknown. In rats, DMI reduces the activity of the locus ceruleus, a major source of NE innervation of the hypothalamic paraventricular nucleus, the site of CRH neurons. Naloxone induces ACTH and cortisol release in humans through a noradrenergic-mediated mechanism and a probable consequent stimulation of hypothalamic CRH release. To study the interaction of these drugs on NE neurotransmission and, hence, HPA axis activity in humans, we administered DMI alone and with naloxone in a randomized, double blind, placebo-controlled protocol in eight healthy male volunteers. DMI (75 mg, orally) was given 180 min before naloxone (125 micrograms/kg BW, i.v.). Plasma ACTH and cortisol were measured at frequent intervals from 60 min before to 120 min after naloxone treatment. Plasma cortisol levels were 77% higher 180 min after DMI compared to those after placebo treatment (287 +/- 17 vs. 162 +/- 14 nmol/L; P = 0.000005). DMI reduced the naloxone-induced rise in cortisol (P = 0.02), but there was no change in the integrated cortisol response. The increase in basal plasma ACTH levels after DMI treatment did not reach statistical significance. DMI significantly increased systolic blood pressure and heart rate consistent with an effect on the noradrenergic control of the cardiovascular system. In summary, DMI increased basal cortisol levels consistent with facilitation of NE neurotransmission and, hence, hypothalamic CRH release. However, DMI had no enhancing effect on naloxone-induced cortisol release. This contrasts with the synergy observed when non-antidepressant agents that increase NE neurotransmission are given with naloxone to humans. DMI increases glucocorticoid feedback sensitivity in the rat HPA axis after several weeks through up-regulation of central corticosteroid receptors. However, this slowly developing effect is unlikely to occur during these acute studies. The effect of DMI on naloxone-induced cortisol release is consistent with an inhibitory effect on central noradrenergic control of ACTH release, perhaps at the locus ceruleus. This is the first human study to suggest an inhibitory effect of DMI on central noradrenergic control of ACTH release.
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PMID:The effect of desipramine on basal and naloxone-stimulated cortisol secretion in humans: interaction of two drugs acting on noradrenergic control of adrenocorticotropin secretion. 788 33

Neuropeptides were examined in relation to suicidal behavior and its repetition in depression. There were no significant differences between depressed patients who had or had not attempted suicide for cerebrospinal fluid (CSF) concentrations of neuropeptide Y, somatostatin, diazepam-binding inhibitor, GABA, or corticotropin releasing hormone. A 5-year follow-up was carried out. There were no significant differences between depressed patients who did or did not reattempt suicide during the follow-up or who had never attempted for CSF concentrations of any of the neuropeptides measured. These negative results suggest that these neuropeptides are probably not major determinants of suicidal behavior or its repetition in depression.
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PMID:Neuropeptides in relation to suicidal behavior in depression. 790 97

This paper describes the construction of a computer model that simulates the hypothalamic-pituitary-adrenal axis (HPA axis) regulation of cortisol production. It is presented to illustrate the process of physiological modeling using standard "off the shelf" technologies. The model simulates components of the HPA axis involved in the continuous secretion and elimination of cortisol, adrenocorticotropin (ACTH), and corticotropin releasing hormone (CRH). The physiological relations of these component pieces were modeled based on the current knowledge of their functioning. Rate constants, half lives, and receptor affinities were assigned values derived from the experimental literature. At its current level of development the model is able to accurately simulate the timing, magnitude and decay of the ACTH and cortisol concentration peaks resulting from the ovine-CRH stimulation test in normal and hypercortisolemic patients. The model will be used to predict the effects of lesions in different components of the HPA axis on the time course of cortisol and ACTH levels. We plan to use the model to explore the experimental conditions required to distinguish mechanisms underlying various disorders of the HPA axis, particularly depression. Efforts are currently underway to validate the model for a large variety of normal and pathological perturbations of the HPA axis.
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PMID:A computer simulation of the hypothalamic-pituitary-adrenal axis. 794 52

A 68-year-old man was hospitalized in August, 1990 with general malaise, loss of energy, poor appetite and severe depression. He had experienced depressed moods, markedly diminished interest, feelings of worthlessness, diminished ability to think, general malaise and muscle weakness beginning in November, 1989. He was treated for depression at another hospital until his emergent admission to our hospital because of difficulty in walking. Laboratory studies disclosed hyponatremia, low plasma ACTH level (4.2 pmol/L), and a low cortisol level (27.6 nmol/L). Rapid ACTH test elicited an increase in serum cortisol from 75.6 nmol/L to 361.2 nmol/L at 30 min. Ovine corticotropin releasing hormone (CRH) did not stimulate secretion of either ACTH or cortisol. Human growth hormone releasing hormone (GRH) together with thyrotropin releasing hormone (TRH) elicited a normal response of TSH and low responses of GH and PRL. The patient's serum autoantibodies to anterior pituitary cell membranes using GH3 rat pituitary cells and AtT-20 mouse pituitary cells were positive. On the basis of these data, the diagnosis of selective ACTH, GH and PRL deficiency was made and thought to have been caused by lymphocytic adenohypophysitis. Following cortisol replacement therapy, he quickly regained his appetite and was restored to a normal mental state of being.
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PMID:Severe depression associated with ACTH, PRL, and GH deficiency: a case report. 795 79

In a sub-population of endogenously depressed patients, disturbances of the hypothalamic-pituitary-adrenal axis can be observed. Increased cortisol and CRH levels combined with normal ACTH concentrations have often been reported. Corticosteroids appear to play a role in the mood changes, in depressed subjects. However, their mechanism of action is unknown. In animal experiments, the involvement of corticosteroids in stressor-induced learning was investigated. Three paradigms were used. In the Porsolt swimtest an animal had to learn to adapt to an inescapable situation. In the lithium chloride conditioned taste aversion an animal learned to avoid sugar water. In the amphetamine sensitization a second injection of amphetamine caused a potentiated response, because of conditioning. All three conditions appeared to be stressful because they induced a corticosterone release. When adrenalectomized (ADX) mice were compared to control animals it appeared that, in all three paradigms, their memory function was disturbed. The data indicated that this was a specific glucocorticoid-mediated effect since corticosterone and dexamethasone injections were able to reverse the ADX-induced deficit. The ADX-induced disturbances were only observable at moderate stress levels. More severe stressors (lower water temperature in the Porsolt swimtest, higher lithium chloride and amphetamine doses) also made ADX mice remember their previous experiences. The results suggest that corticosteroids are involved in the consolidation of stressful events and the corresponding coping responses. They play, however, only a role in the case of moderate stressors. In ADX animals no stressor-induced corticosterone increase can occur and therefore these animals only remember severe stressors. In a depressed patient basal steroid levels are increased and consequently very mild stressors, which induce only a small extra steroid release, will be remembered. The remembering of all these negative experiences might be of importance for the development and maintenance of the depression.
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PMID:Involvement of corticosteroids in the processing of stressful life-events. A possible implication for the development of depression. 804 8

In the LEW/N rat model, a decreased hypothalamic-pituitary-adrenal (HPA) axis response to inflammatory and immune mediators confers susceptibility to the development of a variety of inflammatory and immune diseases, including experimental allergic encephalomyelitis. In humans with optic neuritis, early intervention with steroids is associated with a decrease in the number of patients who go on to develop multiple sclerosis (MS). The current study was designed to determine whether patients with MS show evidence of a hypoactive HPA axis. Thirteen patients with MS were studied at baseline and with provocative tests of HPA axis function [ovine CRH, arginine vasopressin (AVP), and ACTH stimulation]. Compared to matched controls, patients with MS had significantly higher plasma cortisol levels at baseline. Despite this hypercortisolism and in contrast to patients with depression who had similar elevations in plasma cortisol levels, patients with MS showed normal, rather than blunted, plasma ACTH responses to ovine CRH, suggesting that the pathophysiology of hypercortisolism in MS is different from that in depression. Patients with MS also showed blunted ACTH responses to AVP stimulation and normal cortisol responses to high and low dose ACTH stimulation. Taken together, these findings are compatible with data from studies of experimental animals exposed to chronic inflammatory stress, which showed mild increased activation of the HPA axis with increased relative activity of AVP in the regulation of the pituitary-adrenal axis. These data do not support a role for hypocortisolism in MS once the disease is established.
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PMID:Multiple sclerosis is associated with alterations in hypothalamic-pituitary-adrenal axis function. 807 72

1. The sympathetic superior cervical ganglia (SCG) provide innervation to the pineal gland and median eminence through the internal carotid nerve and to the thyroid and parathyroid glands through the external carotid nerve. 2. Postsynaptic activation in median eminence nerve endings shortly after superior cervical ganglionectomy (SCGx) was accompanied by a depression of LH and FSH release and by a 3-5 day delay in rat estrous cyclicity. A decrease in TSH and GH release and an increase in ACTH and prolactin release were also found. These effects were accompanied by a) an increase in medial basal hypothalamic (MBH) LHRH, TRH and GHRH, b) a decrease in MBH somatostatin, AVP and CRH, and c) a normal adenohypophyseal response to hypophysiotropic hormones. Neurohypophyseal AVP release decreased during degeneration of sympathetic nerve terminals in the neurohypophyseal lobe after SCGx. The effects were generally mediated by alpha 1-adrenoceptors and were pineal gland. 3. In thyroid and parathyroid tissue the following events were observed during the wallerian degeneration phase after SCGx: a) alpha 1-adrenoceptor inhibition of thyroxine (T4) release, b) alpha 1-adrenoceptor inhibition, together with beta-adrenoceptor stimulation, of calcitonin release, and c) alpha 1-adrenoceptor inhibition of parathyroid hormone release. Thyroid sympathetic nerves also modulate slow phenomena such as compensatory thyroid growth after partial thyroidectomy. 4. In rats subjected to cholinergic decentralization of the thyroid gland, a decrease of plasma T4 and an increase of plasma TSH, as well as an impaired goitrogenic and thyroid compensatory response were detectable. The calcitonin and PTH response to changes in calcium levels increased after regional parasympathetic denervation. 5. The results indicate that cervical autonomic nerves constitute a parallel pathway through which the brain communicates with the endocrine system.
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PMID:Peripheral neuroendocrinology of the cervical autonomic nervous system. 808 Dec 83


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