Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the literature, activation of the hypothalamo-neurohypophyseal system (HNS) in normal aging has been demonstrated in rat and human. This activation might be secondary to an age-related decline in vasopressin binding sites in the kidney, or to cell loss in the supraoptic (SON) and paraventricular nuclei (PVN) and/or to an age-related decline in noradrenergic (NA) innervation of the hypothalamus. This study shows neuronal hypertrophy in SON and PVN in normal aging and an additional hypertrophy in Alzheimer's disease. No cell loss could be demonstrated in both conditions.
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PMID:Neuronal hypertrophy in the human supraoptic and paraventricular nucleus in aging and Alzheimer's disease. 231 42

Concentrations of vasopressin (AVP) and monoamine metabolites (HVA, 5-HIAA, MHPG) in cerebrospinal fluid (CSF) were measured and compared with memory functions in patients with dementia of Alzheimer type (DAT) and control subjects. CSF concentrations did not differ between the DAT patients and the controls, or between patients with different degrees of dementia. There were no correlations between concentrations of vasopressin and monoamine metabolites in CSF or between the CSF measures and psychological test scores, except for a correlation between CSF HVA and immediate and delayed story recall. These data suggest that probable damage to the vasopressinergic and monoaminergic systems in DAT is not reflected in the CSF of patients in early stages of the disease, nor is a deficit in these systems or their interaction the primary cause of cognitive impairment in DAT.
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PMID:Vasopressin levels in CSF of Alzheimer patients: correlations with monoamine metabolites and neuropsychological test performance. 247 86

Receptors for neurotransmitters can be visualized and characterized using in vitro tissue slice binding techniques and quantitative autoradiography. In this article, the general methods used in studies of this type are outlined and specific application to the study of catecholamine and neuropeptide receptors in rat and human brain tissue are described. Receptor autoradiography is used to examine regulation of dopamine receptor density in response to denervation and replacement of dopamine using brain transplants. Morphological and pharmacological aspects of vasopressin receptor ontogeny in the rat brain are examined. Finally, autoradiographic data on catecholamine receptor localization and characterization in the human hypothalamus, locus coeruleus, and frontal cortex are presented and discussed with reference to their applications in the study of neuropsychiatric disorders such as schizophrenia and senile dementia of the Alzheimer's type.
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PMID:Localization and measurement of neurotransmitter receptors in rat and human brain by quantitative autoradiography. 253 20

The neuropeptide vasopressin (VP) is released from the neurohypophysis into the circulation where it acts as antidiuretic hormone on the kidney. In addition, VP is present in nerve cells and fibers in several areas in the rodent and primate brain where it acts as a neurotransmitter or neuromodulator. In the human brain a marked decrease in total cell number and VP cell number was observed in senescence in the suprachiasmatic nucleus, the hypothalamic nucleus regulating circadian rhythms. This degeneration was even more pronounced in Alzheimer's disease (AD) and might be related to the disturbances in sleep-wake cycle and endocrine rhythms which occur in this condition. No degenerative changes were observed with aging or in AD in the human hypothalamo-neurohypophyseal system (HNS); on the contrary, total cell numbers remain unaltered and the VP cells in this system are activated in senescence, probably in compensation for decreased sensitivity of the kidney to VP. It is proposed that this activation may prevent degeneration of the VP cells in the HNS. The extrahypothalamic VP innervation in the male rat brain was shown to be diminished in senescence in a number of areas. This innervation, which was previously shown to depend on plasma levels of sex-steroids, could be restored in a number of brain structures by subcutaneous testosterone administration to senescent male rats for one month. Reversibility of changes in VP innervation in the senescent rat brain through peripheral testosterone supplementation might open new possibilities for the development of therapeutic strategies in age-related disorders of the central nervous system.
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PMID:Changes in vasopressin neurons and fibers in aging and Alzheimer's disease: reversibility in the rat. 269 91

Alzheimer's disease is a progressive deterioration of neuropsychological functioning. One of the main neuropathological correlates of the disease is a drop-out of cholinergic neurons within the central nervous system. The neuropeptide that is responsible for water homeostasis and defense against dehydration, vasopressin, is also under direct cholinergic control. Several studies have suggested that in Alzheimer's disease there has been a trend toward lower vasopressin levels than in age-matched controls. In order to improve discrimination of normal from diminished vasopressin levels, nine subjects with Alzheimer's disease (mean age 65 +/- 2 years) and nine age- and sex-matched controls (68 +/- 3 years) underwent a mild provocative challenge of overnight fluid restriction. Individuals with Alzheimer's disease had a greater degree of dehydration, with overnight serum osmolality of 313 +/- 4 vs 300 +/- 3 Mosmol/kg, P = .01, and diminished "thirst" as measured by water ingested in one hour of ad libitum water intake. Eight of the nine with Alzheimer's disease had levels of vasopressin which, by extrapolation, appear to be subnormal for their serum osmolalities, whereas seven of the nine control subjects has vasopressin levels within or above the reference range (P less than .05). Elderly individuals with Alzheimer's disease may be at increased risk of dehydration during periods of fluid restriction due to the loss of normal physiological responses of "thirst" and vasopressin secretion.
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PMID:Vasopressin response to dehydration in Alzheimer's disease. 276 Mar 76

CSF neurotransmitter markers may reflect neurochemical alterations in Alzheimer's disease (AD). The best studied neurochemical deficit in AD is that of acetylcholine. Both acetylcholinesterase and butyrylcholinesterase activity have been reported to be reduced in some but not all studies of AD CSF. Studies of monoamine metabolites have also been controversial but most authors have found reduced concentrations of CSF HVA, lesser reductions in HIAA and no change in MHPG. CSF GABA concentrations have been found to be reduced in AD. Studies of CSF neuropeptides in AD have shown reduced concentrations of somatostatin and vasopressin, normal concentrations of vasoactive intestinal polypeptide and either normal or decreased concentrations of beta-endorphin and corticotropin releasing factor. Although no individual CSF neurochemical markers are specific for AD it may be possible to develop a profile of several neurochemical markers which will have enhanced specificity.
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PMID:CSF neurotransmitter markers in Alzheimer's disease. 287 17

The discovery of neuropeptides in mammalian nervous tissue has proceeded at an astonishing pace in recent years, encouraged by novel detection techniques which allow peptides to be extracted and sequenced before their biological activity has been determined (Mutt 1983; Sudcliffe et al. 1983). Most of these methods, poached from molecular biology, are nowadays reversing former trends which evolved either as a systematic search for factors known to control pituitary hormone release (vasopressin and oxytocin), for instance, or as an endeavour to find endogenous ligands for newly discovered receptors (the endorphins) (see Krieger 1983 for review). Neuropeptide tyrosine (NPY) has emerged as an important member of this new generation of peptides, not least because it is the most abundant and widely distributed in the mammalian brain. However, despite the considerable attention this peptide has attracted, we are far from understanding its functional significance. The following account traces the history of NPY and appraises some of the literature in an attempt to raise some speculation concerning its function; several reviews on this peptide already exist (Emson and de Quidt 1984; Solomon 1985; Allen and Bloom 1986; Gray and Morley 1986), Particular attention is paid to studies which have recently suggested that NPY might be involved with the pathogenesis of two neurodegenerative disorders, Huntington's chorea and Alzheimer's disease.
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PMID:The neuropeptide Y-immunoreactive neuronal system: discovery, anatomy and involvement in neurodegenerative disease. 295 70

The neuropeptides vasopressin, adrenocorticotropin (ACTH), and beta-endorphin seem to have important effects on memory and learning. Animal studies attempting to demonstrate these effects are difficult to interpret because of the complexity of behavior that is described as "learning" and the impossibility of assessing verbal learning in animals. This article therefore reviews some of the animal literature on neuropeptides and learning, but focuses primarily upon studies in humans, both in normal volunteers and in patients with neurological disorders. Vasopressin enhances learning under some conditions. Intranasal administration has been associated with improvement on psychometric tests in patients with mild Alzheimer's disease and Korsakoff's psychosis, although these findings are not uniform. It improves performance on memory tests in normal volunteers, but does not seem to improve the memory deficit after head trauma. Cerebrospinal fluid levels are low in patients with Alzheimer's disease. ACTH and melanocyte-stimulating hormone (MSH) are two peptides the primary behavioral effect of which seems to be on attention or goal-motivated behavior rather than on memory processes themselves. Visual discrimination and the ability to continue repetitive tasks are enhanced; in mentally retarded subjects, the administration of ACTH or MSH improves performance on a variety of neuropsychological tests. It does not, however, improve cognitive function in the elderly. Endogenous opioids including beta-endorphin and met-enkephalin seem to have primarily an amnesic effect in animal studies. Their role in human learning is still uncertain, although naloxone, which antagonizes their effects, has been associated with improved cognitive performance in patients with Alzheimer's disease. These data underscore the complexity of the processes associated with human memory and the rudimentary state of our present knowledge. Whatever the mechanisms, however, vasopressin, ACTH, and endogenous opioids seem to have important effects upon memory.
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PMID:Neuropeptides in human memory and learning processes. 299 44

Previous reports have described 5-20% prevalence of hyponatremia in extended care facilities, due largely to drugs or inappropriate antidiuretic hormone secretion. In our 400 bed VA extended care facility, 15 men with organic brain syndrome (Alzheimer's, multi-infarct dementia, anoxic encephalopathy or alcoholism) currently receive Isocal via gastrostomy as the sole source of nutrition. We noted intermittent hyponatremia in about half of these patients, and conducted a chart review to investigate the cause. Mean age was 68 yr (range 46-92); tube feeding duration was 3 mo.-3 yr; 266 Na concentrations were obtained from the charts. Simultaneous with these Na analyses, one of three diets prevailed: (A) mixed foods (3-6 g Na/day) orally before gastrostomy; (B) Isocal supplemented with NaCl to give 2 g Na/day; (C) unsupplemented Isocal providing 1 g Na/day. (B) and (C) had been randomly varied by rotating physicians. Serum Na was directly related to Na intake. On (A), Na was within normal range (135-145 mEq/l) in all men. One patient was hyponatremic during diet (B). During (C), eight patients were hyponatremic. Na was less than 135 mEq/l in 40% of all samples during diet (C) and less than 130 mEq/l in 14%. Changing from diet (A) or (B) to diet (C) caused nearly equivalent declines in Na and Cl; K and HCO-3 were unaffected. No hyponatremic patient took drugs known to cause hyponatremia, or had congestive heart failure, hypoalbuminemia, lipemia or fasting hyperglycemia. At the end of the study, four hyponatremic men were changed from (C) to (B); serum Na became normal in all four patients, without edema or hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hyponatremia in tube-fed elderly men. 308 Apr 61

When compared with those of age-matched control patients the number of nerve cells in the locus caeruleus in 30 patients with Alzheimer's disease is reduced by 65% while nucleolar volume in surviving cells of the locus caeruleus and in those of the paraventricular and supraoptic nuclei of the hypothalamus is reduced by 25%, 48% and 26% respectively. Furthermore the reduction in cell number and nucleolar volume in these 3 cell types are all interrelated, emphasizing the close functional linkage of these cell groups. Similar changes (for age) were seen in a group of 10 patients with a mixed Alzheimer/vascular type dementia and in 6 patients over 50 years of age with Down's syndrome whose brains also showed extensive senile plaque and neurofibrillary tangle formation. This damage to the locus caeruleus and hypothalamic systems is probably responsible for losses of noradrenaline and vasopressin reported in cerebral cortex and hypothalamus; the importance of these changes to the pathogenesis of Alzheimer's disease is emphasized.
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PMID:Changes in Alzheimer's disease in the magnocellular neurones of the supraoptic and paraventricular nuclei of the hypothalamus and their relationship to the noradrenergic deficit. 316 May 17


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