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)

Neuropeptides represent a new class of compounds with important implications for the understanding of the mechanisms and treatment of epileptic disorders. Several systems of peptide modulators--in particular the opioid-like peptides, vasopressin, somatostatin, thyrotropin-releasing hormone (TRH) and ACTH--have partially demonstrated endogenous roles in some forms of epilepsy. Seizures and stressful situations may release endogenous opioid peptides and mediate postictal depression and postictal seizure refractoriness. Vasopressin is believed to increase susceptibility to convulsions and may be involved in the pathogenesis of febrile convulsions. Derangements in TRH regulation may lower thresholds for seizure expression by regulating arousal systems; however, some TRH analogs have proven to be effective anticonvulsants. Long-term alterations in somatostatin regulation could be components of focal epilepsies. ACTH is particularly useful in the treatment of infantile spasms. Pharmacological effects of these and other peptides have potentials for defining new classes of anticonvulsants. Cholecystokinin (CCK) and its analogs, the opioid peptides beta-endorphin and FK33824, TRH analogs, and several dipeptides exhibit potent anticonvulsant properties in chemical, electroshock, and genetic model screens. Convulsant actions of CRF, somatostatin, TRH, vasopressin, and high doses of endorphin or enkephalins may provide new tools to study regulatory mechanisms of cerebral excitability. The enkephalin epileptogenic effect is being developed as a predictive tool for new anti-petit mal anticonvulsants. Advances in molecular biology have identified the genes of particular peptide families. A concept has developed that the large propeptide precursors, coded by these genes, whose processing leads to functional peptide formation and release, regulate peptidergic humoral responses to external stimuli. This idea may have particular application in the understanding of the genetic basis of some seizure states. Techniques for amplification of mRNA expression have identified specific neuronal proteins and peptides. Knowledge of protein and propeptide structural cleavage sites has suggested previously unknown candidates for modular systems in epileptic states. Technological advances in automated peptide sequencing and synthesis have allowed the development of metabolically resistant analogs and antagonist peptides. The anticonvulsant potencies of CCK, TRH, and opioid peptides have been defined more clearly with these methods.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neuropeptides: anticonvulsant and convulsant mechanisms in epileptic model systems and in humans. 287 23

This review of the CNS effects of the neurohypophyseal hormones and related neuropeptides discusses recent data illustrating the significance of these principles in brain function, synthesis, distribution, in particular in extrahypothalamic brain structures, binding sites, and signal transduction. Binding sites for vasopressin of the vascular V1a type have been found in the CNS and there is evidence for the existence of a subtype of the antidiuretic V2 receptor in the brain. Also two types of oxytocin binding sites have been detected. One widely distributed throughout the CNS is comparable to the uterine type receptor and a sexually dimorphic slightly different type is found in the ventromedial nucleus. Vasopressin and oxytocin can be converted to highly selective C-terminal fragments as AVP-(4-9) and OXT-(4-9) and shorter fragments. Conversely they can be acetylated. This almost completely blocks intrinsic activity in bioassays for central and peripheral effects. Such modifications are a good example of the plasticity of a neuropeptide system. For a number of CNS effects of the neurohypophyseal hormones, the whole molecule is required, as it is for their endocrine effects. This is the case for the influence of vasopressin on social communication, temperature regulation, epilepsy, and barrel rotation which may be an animal model of febrile convulsions, and some aspects of the central regulation of the cardiovascular system and for oxytocin on sexual behavior, social communication, and grooming. Nonendocrine C-terminal conversion products seem to exert their effects exclusively on the brain. These neuropeptides modulate learning and memory processes, social recognition, and rewarded behavior. The neuroendocrine and neuropeptide effect of vasopressin and oxytocin and related neuropeptides often exert their CNS effects in an opposite way. Neurochemical and electrophysiological studies suggest that norepinephrine, dopamine, serotonin, and glutamate are the neurotransmitters involved in the influence of the neurohypophyseal hormones and related neuropeptides on brain function. It appears that adequate amounts of vasopressin and oxytocin to induce these effects are released at the appropriate sites of action. It is postulated that the mix of neuropeptides released in the brain in response to environmental changes qualifies the behavioral, neuroendocrine, and immune response and the response of the autonomic nervous and vegetative systems of the organism. Although various other neuropeptides, such as those colocalized in vasopressinergic and oxytocinergic neurons, those produced in pro-opiomelanocortin (POMC) systems, and others, play a role in the modulation of adaptive responses, the neurohypophyseal hormones are unique in that their production sites in the hypothalamus serve the periphery, the pituitary, and the brain.
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PMID:Central nervous system effects of the neurohypophyseal hormones and related peptides. 825 77

Immaturity in water and electrolyte balance in the brain has been considered to increase the susceptibility of young animals and children to febrile convulsions (FCs). Arginine-vasopressin (AVP) is involved in the regulation of several centrally mediated events such as modulation of fever and the ease with which water permeates into and out of the brain. To evaluate the possible role of AVP in the control of water balance and susceptibility to convulsions during fever we measured the AVP concentration in the cerebrospinal fluid (CSF) and plasma of febrile children with or without convulsions. The febrile population consisted of 47 children, of whom 29 experienced seizures during fever. Seven children with epileptic symptoms and 18 children without seizures were included as nonfebrile controls. The CSF AVP concentration in febrile children without seizures and in nonfebrile convulsive children was significantly lower (0.60 +/- 0.07 pmol/l, mean +/- SEM, P < 0.01 and 0.65 +/- 0.19 pmol/l, P < 0.05, respectively) than in nonfebrile children without convulsions (0.83 +/- 0.06 pmol/l). However, the levels of CSF AVP were not significantly different in children with FCs (0.71 +/- 0.06 pmol/l) compared with other groups. CSF AVP correlated with the CSF osmolality (r = 0.33, P = 0.02). No statistical differences in plasma AVP levels between the groups could be found. The present data provide support for the hypothesis of synchronous regulation of osmolality and AVP concentration in CSF. During fever the concentration of CSF AVP was lower in nonconvulsive children compared with nonfebrile nonconvulsive children. CSF AVP levels were not affected in febrile children by convulsions.
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PMID:Vasopressin in the cerebrospinal fluid of febrile children with or without seizures. 873

Pathogenesis of febrile convulsions (FC) is still unknown, suggested causes include the role of antidiuretic hormone (ADH). ADH is an endogenous antypyretic and his excessive production of the consequent hyponatraemia may be the cause of FC in children with susceptibility to this type of seizure. Whereas, interleukin-1 (IL1) is a pyrogenic substances and is involved in the release of AVP. Helminen et al. have reported a significantly higher production of IL1 in culture of peripheral blood monocytes stimulated with lipopolysaccharide (LPS) of children with FC than in the others with fever but without convulsions. More recently Lahat et al. have compared plasma and cerebrospinal fluid ILI levels of children with FC with those of children with fever but without convulsions, but they did not find significant differences. The aims of this study were to determine the IL1 levels in vivo and in the supernatants of cultures of peripheral blood mononuclear cells (PBMC) stimulated or not with LPS in children with FC and in children with fever without FC and to evaluate the influence of ADH and diazepam (DZ) on IL1 production. Blood samples for PBMC cultures were obtained from 11 children with FC on the hospital admission, (group 1) and after 48 hours from treatment with DZ (group 2). The production of IL1 was measured by RIA in the supernatants of the PBMC stimulated with LPS, LPS + DDAVP (synthetic vasopressin), LPS + DZ and in vivo in plasma samples. The control groups were constituted by 9 children with fever and without convulsions (group 3), 4 of them were studied at the end of fever too (group 4), and finally by 9 children in good health (group 5). No significant differences were observed. These results do not support the hypothesis that increased production of IL1 is involved in the pathogenesis of FC in children.
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PMID:[In vivo and in vitro production of interleukin-1 after febrile convulsions]. 1159 68

This report addresses the verification of the hypothesis that arginine-vasopressin affects the formation of hyperthermia-evoked convulsions in early ontogenesis in rats on days 3, 5, 7, and 9 of postnatal life. The modification of experimental febrile convulsions by PACAP (pituitary adenylate cyclase-activating peptide) was investigated; PACAP is a physiological regulator of the neurosecretion of arginine-vasopressin. Arginine-vasopressin (10 microg/rat) and PACAP (0.01 microg/rat) decreased the latency of generalized tonic-clonic convulsions and the time of truncal generalization of convulsive activity on days 3 and 5 of rat development. Animals given arginine-vasopressin (0.1-10 microg/rat) sowed significant increases in the duration of generalized convulsions to the level of status epilepticus on day 9 of life. Conversely, administration of higher doses of PACAP (0.1 microg/rat) increased the threshold of tonic-clonic convulsions on days 3 and 5 and decreased it on days 7 and 9 of postnatal development. The indirect involvement of PACAP in the mechanisms of experimental febrile convulsions is suggested to act via changes in arginine-vasopressin neurosecretion.
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PMID:Peptidergic mechanisms of hyperthermia-evoked convulsions in rats in early postnatal ontogenesis. 1240 2

Febrile seizures are a common occurrence in young children with incidence rates varying from 3-14%, depending on the geographic region. Studies have suggested that an elevated temperature is a factor in their development, though other factors may synergistically lower the seizure threshold. While it is recognized that excessive or rapid dilute fluid intake can cause seizures in young children, and in adults during strenuous physical activity, less focus has been paid to its involvement during febrile illnesses. Young children are more vulnerable to the development of febrile seizures due to their small skull size relative to brain volume. In animals, reduced serum sodium levels have been shown to lower the threshold to convulsive stimuli, while hypertonic saline has been shown to rapidly reverse these effects. Similarly vasopressin, frequently elevated during acute infections, enhances fluid retention and may also be a precipitating factor for febrile seizures. Although an elevated temperature may augment seizure risk, antipyretics have not been shown to prevent them. In fact, some may increase seizure risk through a reduction in urine output. It has long been observed that fluid retention occurs during febrile infections, followed by diuresis during convalescence. This characteristic observation led to recommendations for restricted fluid intake during acute infections dating back more than 2,000 years. Only recently has there been a return to restricted fluid intake for patients with potentially reduced free water excretion. Further studies are required to determine the role of the overall fluid balance in the etiology of childhood febrile seizures.
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PMID:Febrile seizures in young children: role of fluid intake and conservation. 1776 30