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)

It has been suggested that abnormalities of thirst and vasopressin secretion commonly coexist with Kallmann's syndrome. Out-patient plasma osmolality, plasma sodium and 24-hour urine volume were similar in 10 patients with Kallmann's syndrome and 10 matched controls. Six patients underwent dynamic testing of osmoregulation with hypertonic sodium chloride infusion. There were similar rises in plasma AVP concentration in patients (0.4 +/- 0.1-6.2 +/- 1.2 pmol/l, P less than 0.001) and controls (0.4 +/- 0.1-5.7 +/- 1.0 pmol/l P less than 0.001). Thirst ratings rose in similar fashion in patients (0.7 +/- 0.3-6.2 +/- 1.0 cm, P less than 0.001) and controls (1.0 +/- 0.3-7.2 +/- 0.5 cm. P less than 0.001). Drinking rapidly abolished thirst and lowered AVP concentrations in both groups before major changes in plasma osmolality occurred. Linear regression analysis defined similar osmotic thresholds for thirst onset and vasopressin release in the two groups, and there was no difference in the calculated sensitivity of the osmoreceptor/vasopressin secretory unit as defined by the slopes of the regression lines. We conclude that osmoregulation is normal in Kallmann's syndrome.
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PMID:Osmoregulation of thirst and vasopressin secretion in Kallmann's syndrome. 260 90

Seven subjects with Kallmann's syndrome were studied to determine whether they had disturbances of fluid homeostasis. Simultaneous measurements of urine and plasma osmolality (Uosm and Posm, respectively) were made during free access to fluids. The Uosm-Posm relationship was abnormal in five patients on at least one occasion. Patient 2 was frequently overhydrated (Posm less than or equal to 280 mosmol/kg) and patient 5 excreted a dilute urine when his Posm was 290 mosmol/kg. The three subjects (1, 5, and 7) tending to have an increased Psom (greater than or equal to 300 mosmol/kg) were able to concentrate their urine (Uosm greater than 800 mosmol/kg) and denied polyuria and polydipsia. Their elevated Posms could be explained by impairment of thirst, rather than increased excretion of water, because the patients concentrated their urines at normal Posms during fluid deprivation. The osmotic threshold for vasopressin release was decreased (Posm = 270.6 mosmol/kg) in one patient and increased (Posm greater than or equal to 295 mosmol/kg) in two others of the seven patients. The elevated osmotic threshold was not due to chronic hyperosmolality or a generalized defect in vasopressin secretion. In the patient with the highest osmotic threshold (Posm = 296 mosmol/kg) and Posms between 289--301 mosmol/kg during free access to fluid, the osmotic threshold decreased to only 293 mosmol/kg after 6 weeks of adequate hydration and desmopressin acetate. However, in response to hypotension induced by trimethaphan, he increased his plasma vasopressin from 1--26 microU/ml. In conclusion, some patients with Kallmann's syndrome may have osmoreceptor dysfunction and abnormal thirst regulation, indicating more extensive hypothalamic involvement than previously appreciated.
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PMID:Altered osmotic threshold for vasopressin release and impaired thirst sensation: additional abnormalities in Kallmann's syndrome. 710 21

The hypothalamus has been claimed to be involved in a great number of physiological functions in development, such as sexual differentiation (gender, sexual orientation) and birth, as well as in various developmental disorders including mental retardation, sudden infant death syndrome (SIDS), Kallman's syndrome and Prader-Willi syndrome. In this review a number of hypothalamic nuclei have therefore been discussed with respect to their development in health and disease. The suprachiasmatic nucleus (SCN) is the clock of the brain and shows circadian and seasonal fluctuations in vasopressin-expressing cell numbers. The SCN also seems to be involved in reproduction, adding interest to the sex differences in shape of the vasopressin-containing SCN subnucleus and in its VIP cell number. In addition, differences in relation to sexual orientation can be seen in this perspective. The vasopressin and VIP neurons of the SCN develop mainly postnatally, but as premature children may have circadian temperature rhythms, a different SCN cell type is probably more mature at birth. The sexually dimorphic nucleus (SDN, intermediate nucleus, INAH-1) is twice as large in young male adults as in young females. At the moment of birth only 20% of the SDN cell number is present. From birth until two to four years of age cell numbers increase equally rapidly in both sexes. After this age cell numbers start to decrease in girls, creating the sex difference. The size of the SDN does not show any relationship to sexual orientation in men. The large neurosecretory cells of the supraoptic (SON) and paraventricular nucleus (PVN) project to the neurohypophysis, where they release vasopressin and oxytocin into the blood circulation. In the fetus these hormones play an active role in the birth process. Fetal oxytocin may initiate or accelerate the course of labor. Fetal vasopressin plays a role in the adaptation to stress--caused by the birth process--by redistribution of the fetal blood flow. Corticotropin-releasing hormone (CRH) neurons of the PVN play a central role in stress response. Thus fetal CRH neurons may play a role in the timing of the moment of birth. Recently, alterations have been described in peptidergic, aminergic and cholinergic transmitters in the hypothalamus in SIDS. Future research will have to establish whether these changes are part of the course of SIDS. A large proportion of the SON and PVN neurons also produce tyrosine hydroxylase (TH). In neonates the majority of TH-immunoreactive neurons colocalizes vasopressin, while in the adult the majority of TH-positive neurons colocalizes oxytocin.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Development of the human hypothalamus. 764 57

A case is presented of a male with Kallmann's syndrome who at the age of 27 developed central diabetes insipidus. Previously, Kallmann's syndrome has been found to be associated with an altered osmotic threshold for vasopressin release and impaired thirst sensation, but to our knowledge, this is the first reported association with diabetes insipidus.
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PMID:Kallmann's syndrome with diabetes insipidus. 1525

A few examples of hypothalamic, peptidergic disorders leading to clinical signs and symptoms are presented in this review. Increased activity of corticotropin-releasing hormone (CRH) neurons in the paraventricular nucleus (PVN) and decreased activity of the vasopressin neurons in the biological clock and of the thyroxine-releasing hormone (TRH) neurons in the PVN contribute to the signs and symptoms of depression. In men, the central nucleus of the bed nucleus of the stria terminalis (BSTc) is about twice as large and contains twice as many somatostatin neurons as in women. In transsexuals this sex difference is reversed, pointing to a role of this structure in gender. Luteinizing hormone-releasing hormone (LHRH) neurons are formed in the fetal olfactory placade and migrate along the terminal nerve fibers into the hypothalamus. In Kallmann's syndrome the migration process of the LHRH (gonadotropin-releasing hormone) neurons is aborted, which explains the joint occurrence of hypogonadotropic hypogonadism and anosmia in this syndrome. In postmenopausal women, the neurons of the infundibular nucleus hypertrophy and become hyperactive because of the disappearance of the estrogen feedback and contain hyperactive peptidergic neurons. Climacteric flushes may be caused by hyperactivity of the neurokinin-B or LHRH neurons in this nucleus. The hypocretin (orexin) neurons in the perifornical area are involved in sleep. In narcolepsy with cataplexy, a loss of these neurons, probably due to an autoimmune process, is found. Obese subjects with a mutation in the gene that encodes for leptin, the preproghrelin gene, or the alpha-melanocyte-stimulating hormone (alpha-MSH) gene have been described. Decreased numbers and activity of the oxytocin neurons in the PVN may be responsible for the absence of satiety in Prader-Willi syndrome. Moreover, a glucocorticoid receptor polymorphism is associated with obesitas and dysregulation of the hypothalamus-pituitary-adrenal axis. In contrast, two single nucleotide polymorphisms (SNPs) of the AGRP gene have been associated with anorexia nervosa.
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PMID:Neuropeptides in hypothalamic neuronal disorders. 1554 16

Septo-optic dysplasia (SOD), also referred to as de Morsier syndrome, is a rare congenital condition, characterized by two of the classic triad features: midline brain abnormalities, optic nerve hypoplasia (ONH) and pituitary endocrine dysfunction. We report 5 children with SOD, originally referred to be evaluated due to short stature, who also presented bilateral optic nerve hypoplasia, nystagmus and development delay. In 4 of the patients, we identified neuroimaging abnormalities of the hypothalamo-pituitary axis such as anterior pituitary hypoplasia (3/5), ectopic posterior pituitary (4/5), thin or absent stalk (3/5) and empty sella (1/5). We also encountered diverse pituitary deficiencies: growth hormone (3/5), adrenocorticotropic hormone (3/5), thyroid-stimulating hormone (2/5) and antidiuretic hormone (1/5). Only one child presented intact pituitary function and anatomy. Although rare, SOD is an important cause of congenital hypopituitarism and it should be considered in children with optic nerve hypoplasia or midline brain abnormalities for early diagnosis and treatment.
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PMID:Septo-optic dysplasia. 2060 44