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

The somatotropic axis interacts with the central nervous system (CNS) on several levels. Growth hormone (GH) and insulin-like growth factor-I (IGF-I) receptors are expressed in many brain areas including the hippocampus, pituitary and hypothalamus. GH and IGF-I can pass the blood-brain barrier by an as yet not completely understood mechanism. They can also be produced in the brain and thus act via paracrine/autocrine mechanisms. GH and IGF-I are important factors in the development and differentiation of the CNS and have protective properties in dementia, and in traumatic and ischemic injury of the CNS. An improvement in cognitive functioning in GH-deficient patients by GH substitution has been shown. Significant results could, however, only be achieved with supraphysiological doses. In some studies, a correlation between IGF-I and cognitive function in the elderly has been found. GH has an important impact on mood and well-being with GH secretory capacity being reduced in depression. Pulsatile GH secretion is closely related to slow wave sleep (SWS) with SWS being stimulated by GH releasing hormone and rapid eye movement (REM) sleep by GH.
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PMID:Central effects of the somatotropic system. 1458 82

It is well established that cocaine stimulates monoamine transmission by blocking reuptake of norepinephrine (NE), dopamine and serotonin into nerve cells, yet few investigations have addressed the effects of chronic cocaine on NE function. In the present study, we examined the effects of repeated cocaine injections on neuroendocrine responses evoked by the alpha2-adrenergic receptor agonist, clonidine. Previous findings show that clonidine increases pituitary growth hormone (GH) secretion by a central mechanism involving postsynaptic alpha2-adrenergic receptors. Male rats previously fitted with indwelling jugular catheters received two daily injections of cocaine (15 mg/kg, i.p.) or saline for 7 days. At 42 h and 8 days after treatment, rats were challenged with clonidine (25 microg/kg, i.v.) or saline, and serial blood samples were withdrawn. Plasma GH and corticosterone levels were measured by radioimmunoassay. Prior cocaine exposure did not affect basal levels of either hormone. However, cocaine-pretreated rats displayed a significant reduction in clonidine-evoked GH secretion at 42 h, and this blunted response was still apparent 8 days later. Corticosterone responses produced by clonidine were similar regardless of pretreatment. The present data suggest that withdrawal from repeated cocaine injections may be accompanied by desensitization of postsynaptic alpha2-adrenoreceptors coupled to GH secretion. Since human patients with depression often exhibit blunted GH responses to clonidine, our findings provide evidence that cocaine withdrawal might produce depressive-like symptoms via dysregulation of NE mechanisms.
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PMID:Evidence for alterations in alpha2-adrenergic receptor sensitivity in rats exposed to repeated cocaine administration. 1509 82

Growth hormone replacement in adult growth hormone deficient patients improves psychological well-being and the quality of life. The aim of this study was to investigate relationship between changes in mood, cognitive functioning, quality of life, changes in body composition and hormone concentration at baseline and six months after treatment with human recombinant growth hormone. Eighteen adult patients with growth hormone deficiency syndrome were recruited to the study. Growth hormone was administered in doses of 12 IU per week in an open design. After 6 months of growth hormone replacement therapy the psychological functioning improved significantly on mood scales (Profile of Mood State) and on a cognitive performance tests. Changes in quality of life scale were trivial. After growth hormone treatment serum concentration of Insulin like growth factor -1 (IGF-1) and triiodothyronine increased and concentration of serum free thyroxine decreased significantly in comparison to basal concentration. There were no significant differences in changes of plasma cortisol, thyrotropin and growth hormone concentrations. Improvement on Profile of Mood State global score as well as on Vigor-Activity subscale correlated significantly with increase in IGF-1 concentration. Improvement on Profile of Mood State Vigor-Activity subscale correlated with increase in water body mass and improvement on Hospital Anxiety and Depression scale depression subscale correlated with decrease in cortisol concentration. The study shows that growth hormone replacement improves mood and cognition in adult growth hormone deficient patients. This improvement is related to changes in water body mass as well as to endocrine changes.
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PMID:Psychological functioning after growth hormone therapy in adult growth hormone deficient patients: endocrine and body composition correlates. 1529 90

This study was designed to compare growth hormone, cortisol and prolactin responses to physical exercise in depressed patients and healthy comparison subjects. Patients fulfilled the DSM-IV diagnostic criteria for current major depressive disorder; subjective depressive symptoms were rated with Montgomery-Asberg Depression Rating Scale (MADRS) immediately before the experiment. Growth hormone, cortisol and prolactin were measured before and immediately after physiologically stressful bicycle cardiopulmonary exercise test. After exercise, there were three additional hormone measurements, with 30-min intervals. No significant difference was found in baseline growth hormone, cortisol or prolactin levels between patients and the control group. Plasma growth hormone and cortisol levels increased significantly during physical exercise in both patients and controls and returned to baseline in 90 min. There was no significant difference in growth hormone or cortisol responses to physical exercise between the two groups. However, prolactin levels increased only in the depressed patients group during the exercise. We hypothesize that acute exercise may have a stronger effect on serotonin (5-HT) release in depressed patients, which is reflected in increased plasma prolactin concentration.
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PMID:Growth hormone, cortisol and prolactin responses to physical exercise: higher prolactin response in depressed patients. 1538 Aug 61

The dopaminergic system has been implicated in the pathogenesis and treatment of a variety of neuropsychiatric disorders, such as schizophrenia, depression, and addiction. (Dys)function of the dopaminergic system may be studied by combining [15O]H2O PET with a dopaminergic drug challenge. In this pilot study we investigated the suitability of the dopamine reuptake blocker methylphenidate (MP) as a dopaminergic probe. Measurements of regional cerebral blood flow (rCBF) were made at 10 and 30 min after placebo and MP (0.25 mg/kg) injection to seven healthy volunteers. During scanning the behavioral condition of the subjects was standardized using a continuous performance task. Growth hormone levels were assessed and subjective ratings were obtained. MP significantly elevated growth hormone levels. After receiving MP, the subjective experience varied from neutral to highly pleasurable. Ten minutes after MP administration, significant relative increases in rCBF were found in the rostral anterior cingulate (AC), temporal poles, and the supplementary motor area. Significant reductions were seen in the superior temporal gyri, right medial frontal gyrus, and right inferior parietal cortex. At 30 min after MP administration, increases were seen in the AC, temporal pole, and right cerebellum. No changes were observed in the striatum. The activation in the right rostral AC was significantly higher in the subjects with the highest euphoria scores compared to the subjects with minimal MP-induced changes in euphoria. We suggest that the combined MP challenge with functional imaging, as described in our study, may be a useful tool to study the functional integrity of the dopaminergic system in psychiatric disorders.
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PMID:Methylphenidate-induced activation of the anterior cingulate but not the striatum: a [15O]H2O PET study in healthy volunteers. 1708 Apr 42

Previous studies revealed that stress is a pivotal factor in the regulation of growth. Psychological harassment may result in psychosocial dwarfism with delayed puberty, short stature and depression. Growth hormone (GH) secretion is suppressed by stress, possibly via the attenuation of growth hormone-releasing hormone (GHRH) secretion. However, the morphological substrate of this phenomenon has not been elucidated yet. Since neuropeptide Y (NPY) levels in the plasma is increased by administration of various stressors, the common consensus is that NPY plays a crucial role in the stress response. In the present study, we examined the putative juxtapositions between the NPY- and GHRH-immunoreactive (IR) systems in the human hypothalamus using double-label immunohistochemistry. Our findings revealed that the majority of the GHRH-IR perikarya formed intimate associations with NPY-IR fiber varicosities. The majority of these juxtapositions were found in the infundibular nucleus/median eminence where NPY-IR fiber varicosities often covered a significant surface area of the GHRH neurons. Since the juxtapositions between the GHRH-IR perikarya and NPY-IR fiber varicosities may be functional synapses, they may represent the morphological substrate of stress-suppressed GH secretion. The large number of contacting elements indicates that NPY plays a pivotal role in GH release, and may be considered as a major factor in the attenuation of growth by stress in humans.
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PMID:Associations between the human growth hormone-releasing hormone- and neuropeptide-Y-immunoreactive systems in the human diencephalon: a possible morphological substrate of the impact of stress on growth. 1842 83

Over the past few decades, there has been an unprecedented rise in off-label use and misuse of testosterone, growth hormone, thyroid hormone, and adrenal supplements. Testosterone therapy is often promoted to men for the treatment of low energy, lower libido, erectile dysfunction, and other symptoms. Growth hormone is used in attempts to improve athletic performance in athletes and to attenuate aging in older adults. Thyroid hormone and/or thyroid supplements or boosters are taken to treat fatigue, obesity, depression, cognitive impairment, impaired physical performance, and infertility. Adrenal supplements are used to treat common nonspecific symptoms due to "adrenal fatigue," an entity that has not been recognized as a legitimate medical diagnosis. Several factors have contributed to the surge in off-label use and misuse of these hormones and supplements: direct-to-consumer advertising, websites claiming to provide legitimate medical information, and for-profit facilities promoting therapies for men's health and anti-aging. The off-label use and misuse of hormones and supplements in individuals without an established endocrine diagnosis carries known and unknown risks. For example, the risks of growth hormone abuse in athletes and older adults are unknown due to a paucity of studies and because those who abuse this hormone often take supraphysiologic doses in sporadic intervals. In addition to the health risks, off-label use of these hormones and supplements generates billions of dollars of unnecessary costs to patients and to the overall health-care system. It is important that patients honestly disclose to their providers off-label hormone use, as it may affect their health and treatment plan. General medical practitioners and adult endocrinologists should be able to begin a discussion with their patients regarding the unfavorable balance between the risks and benefits associated with off-label use of testosterone, growth hormone, thyroid hormone, and adrenal supplements. Abbreviations: DHEA = dehydroepiandrosterone; FDA = U.S. Food and Drug Administration; GH = growth hormone; IGF-1 = insulin-like growth factor 1; LT3 = L-triiodothyronine; LT4 = levothyroxine; T3 = total triiodothyronine; T4 = thyroxine; TSH = thyroid-stimulating hormone.
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PMID:OFF-LABEL USE AND MISUSE OF TESTOSTERONE, GROWTH HORMONE, THYROID HORMONE, AND ADRENAL SUPPLEMENTS: RISKS AND COSTS OF A GROWING PROBLEM. 3216 13


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