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)

Two cases of hyponatremia with intracranial lesions are reported with emphasis on diagnostic value of measurement of antidiuretic hormone (ADH) and atrial natriuretic polypeptide (ANP). Case 1. A 77-year-old female was transferred to our hospital for further care of vegetative state after subarachnoid bleeding on May 23, 1986. She was operated by neck clipping of rt-IC bifurcation aneurysm and lt-internal carotid-posterior communicating aneurysm at another hospital. On admission, computed tomography showed diffuse low density at bilateral thalamus and centrum semiovale. Biochemical analysis revealed hyponatremia (120 mEq/t) with increased natriuresis. Endocrinological date revealed normal plasma ADH and high plasma ANP levels. Patient was treated with infusion of 1% NaCl. Case 2. A 65-year-old male was admitted to our department because of gradual impairment of consciousness and generalized convulsion. Computed tomography showed small low density area at rt-thalamus and lt-cerebellar hemisphere. Biochemical date revealed severe hyponatremia (91 mEq/t) with normal plasma level of ADH and high plasma ANP. He was treated with infusion of 3% NaCl and hyponatremia was improved. The hyponatremia is frequently associated with intracranial disorders such as brain tumor, subarachnoid hemorrhage and head injury. Originally, hyponatremia with natriuresis was thought to be caused by salt wasting. This syndrome was defined as the inability to prevent salt loss in the urine due to undefined natriuretic factor in the brain. However, since 1957, because of introduction of concept of SIADH, it has generally become accepted that patients with natriuresis had SIADH. (ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Hyponatremia with high plasma ANP level--report of two cases with emphasis on the pathophysiology of cerebral salt wasting]. 296 7

The hypothesis that an increase in plasma sodium concentration (PNa) causes an increase in circulating atrial natriuretic polypeptide (ANP) was examined in conscious dogs. NaCl solution in small volume (0.3 ml/kg body wt) and at high concentration (20%) was injected intravenously within 2 s to rapidly increase PNa. PNa rapidly increased to 5.1 +/- 0.3 meq/l. Urinary excretion of sodium and water increased to 4.1 and 2.5 times the control levels, respectively. Plasma vasopressin level increased to 3.7 times the control level. Plasma ANP level (PANP) did not change significantly. PANP corrected for sodium-induced hemodilution did not change either. On a different day, a double amount of sodium (0.6 ml/kg body wt of 20% NaCl solution) was intravenously injected into the dogs. PNa increased by 7.3 +/- 0.4 meq/l, which was significantly more than the increase after the 0.3 ml/kg injection. PANP with or without correction for hemodilution again did not change. These results indicate that a rapid increase in PNa within the physiological range does not cause elevation of circulating ANP. This suggests that ANP does not contribute to the regulation of plasma sodium concentration.
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PMID:Effect of rapid sodium load on circulating atrial natriuretic polypeptide. 296 17

To elucidate the involvement of the brain renin-angiotensin system and the brain atrial natriuretic polypeptide (ANP) system in the regulation of ANP secretion from the heart, the effects of intracerebroventricular administration of angiotensin II and ANP on the plasma ANP level were examined in conscious unrestrained rats. The intracerebroventricular administration of angiotensin II at doses of 100 ng and 1 microgram significantly enhanced ANP secretion induced by volume-loading with 3-mL saline infusion (peak values of the plasma ANP level: control, 220 +/- 57 pg/mL; 100 ng angiotensin II, 1110 +/- 320 pg/mL, p less than 0.01; 1 microgram angiotensin II, 1055 +/- 60 pg/mL, p less than 0.01). The intracerebroventricular injection of angiotensin II at the same doses alone had no significant effect on the basal plasma ANP level. The enhancing effect of central angiotensin II on ANP secretion induced by volume-loading was significantly attenuated by pretreatment with the intravenous administration of the V1-receptor antagonist of vasopressin or with the intracerebroventricular administration of phentolamine. The intracerebroventricular administration of alpha-rANP(4-28) (5 micrograms) had no significant influence on the basal plasma ANP level; however, it significantly attenuated central angiotensin II potentiating effect of volume-loading induced ANP secretion. These results indicate that the brain renin-angiotensin system regulates ANP secretion via the stimulation of vasopressin secretion and (or) via the activation of the central alpha-adrenergic neural pathway, and that the brain ANP system interacts with the brain renin-angiotensin system in the central modulation of ANP secretion from the heart.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Central interaction of the brain atrial natriuretic polypeptide (ANP) system and the brain renin-angiotensin system in ANP secretion from heart--evidence for possible brain-heart axis. 296 40

A detailed analysis of the cytoarchitecture, retinohypothalamic tract (RHT) projections, and immunohistochemical localization of major cell and fiber types within the hypothalamic suprachiasmatic nuclei (SCN) was conducted in five mammalian species: two species of opossum, the domestic cat, the guinea pig, and the house mouse. Cytoarchitectural and immunohistochemical studies were conducted in three additional species of marsupial mammals and in the domestic pig. The SCN in this diverse transect of mammalian taxonomy bear striking similarities. First, the SCN are similar in location, lying close to the third ventricle (3V) dorsal to the optic chiasm (OC), with a cytoarchitecture characterized by small, tightly packed neurons. Second, in all groups studied, the SCN receive bilateral retinal input. Third, the SCN contain immunohistochemically similar elements. These similarities suggest that the SCN developed characteristic features early in mammalian phylogeny. Some details of SCN organization vary among the species studied. In marsupials, vasopressin-like immunoreactive (VP-LI) and vasoactive intestinal polypeptide-like immunoreactive (VIP-LI) cells codistribute primarily in the dorsomedial aspects of the SCN, while in eutherians, VP-LI and VIP-LI cells are separated into SCN subnuclei. Furthermore, the marsupial RHT projects to the periventricular dorsomedial region, whereas the eutherian RHT projects more ventrally in the SCN into the zone that typically contains VIP-LI perikarya.
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PMID:Comparative anatomy of the mammalian hypothalamic suprachiasmatic nucleus. 297 33

Photoaffinity labeling experiments were performed with membranes from rat liver containing V1 vasopressin receptors. Photoreactive analogues of [1-beta-mercaptopropionic acid]vasopressin [( Mpa1], vasopressin, or deamino-vasopressin) retaining a high binding affinity (apparent dissociation constants: 5 X 10(-9) M-3 X 10(-8) M) and agonistic properties were used. The tritium-labeled analogue [Mpa1,Lys(N epsilon-4-azidobenzoyl)8]vasopressin preferentially and specifically labels a 30-kDa polypeptide and with lower efficiency a 38-kDa polypeptide. The analogue [Mpa1,Dab4(N gamma-(N-4-azido-2-nitrophenyl-beta-Ala4]arginine-vasopressin specifically labels the 38-kDa polypeptide. The labeling of these two membrane proteins is completely suppressed by an excess of arginine-vasopressin; bradykinin or angiotensin II do not inhibit the incorporation of the reactive vasopressin analogues into these proteins. The results suggest that the rat hepatic V1 receptor exists in the plasma membrane in an oligomeric form composed of two subunits with a molecular mass of 30 and 38 kDa.
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PMID:Photoaffinity labeling of the V1 vasopressin receptor in plasma membranes from rat liver. 299 3

Two tetrapeptide sequence homologies between mouse epidermal growth factor precursor (mEGFP) and human follitropin (FSH) were revealed by a computer program that identifies identical residues among polypeptide sequences. The two tetrapeptides, Lys-Thr-Cys-Thr (KTCT) and Thr-Arg-Asp-Leu (TRDL), are present in the hormone-specific beta subunit of FSH from all species studied. These tetrapeptides are not present in the alpha subunit, which is common to all pituitary glycoprotein hormones. Both tetrapeptides are also found in mEGFP, and one tetrapeptide, TRDL, is located within the 53-residue form of mEGF purified from mouse submaxillary glands. Computer-generated hydropathy profiles predicted that both tetrapeptides are located in hydrophilic portions of the FSH beta subunit and that TRDL is in a hydrophilic portion of commercially available mEGF. Therefore, the tetrapeptides might be accessible to receptor binding sites for FSH. We report that mEGF inhibits binding of 125I-labeled human FSH to receptors in testis by 50% (I50) at a concentration of 1.8 X 10(-5) M. No binding inhibition was observed by GnRH or arginine-vasopressin at 10(-4) M, neither of which contain the tetrapeptide sequences. FSH beta subunit, which contains both tetrapeptides, also inhibited binding (I50 = 9 X 10(-8) M) of 125I-labeled human FSH to testis receptor. Thus, it appears that FSH beta subunit and mEGF are capable of inhibiting binding of FSH to testicular FSH receptors, presumably through interactions that include the homologous tetrapeptides. This presumption was supported by the observation that the synthetic tetrapeptides (KTCT or TRDL) were also active in inhibiting binding of 125I-labeled human FSH to testis receptor.
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PMID:Inhibition of iodine-125-labeled human follitropin binding to testicular receptor by epidermal growth factor and synthetic peptides. 301 10

A mutant LLC-PK1 cell line, M18, was isolated after a single treatment of the parent culture with N-methyl-N'-nitro-N-nitroso-guanidine. In contrast to LLC-PK1 cells, the mutant did not exhibit production of urokinase-type plasminogen activator (uPA) in response to the hormones calcitonin and vasopressin, but produced the expected levels of uPA upon stimulation by the receptor-independent adenylate cyclase activators forskolin and cholera toxin, as well as by the phosphodiesterase inhibitor isobutylmethylxanthine and the 8-bromo analogue of adenosine cyclic monophosphate, Br8cAMP. The patterns of activation of cAMP-dependent protein kinase were identical to those of uPA induction: calcitonin and vasopressin were without effect, but the response to all other agents was normal. In similar fashion, mutant cell homogenates displayed normal activation of adenylate cyclase upon treatment with sodium fluoride, forskolin, or the non-hydrolyzable GTP analogue guanosine 5'-[beta, gamma-imino]triphosphate, but were unresponsive to calcitonin or vasopressin. The ability of M18 cells to bind radioactively labelled calcitonin and vasopressin was measured. The mutant possessed less than 4% of the normal levels of the receptor binding activity for both hormones. Somatic cell hybrids formed between M18 and LLC-PK1 cells were found to retain normal hormone binding activity and responsiveness to hormones, indicating that the defect in M18 cells was recessive. M18 was concluded most probably to contain a single mutation impairing the function of two distinct polypeptide hormone receptors.
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PMID:Isolation of a mutant LLC-PK1 cell line defective in hormonal responsiveness. A pleiotropic lesion in receptor function. 302 58

The mutant LLC-PK1 cell lines FIB6 and FIB5/N4 were examined for responsiveness to the polypeptide hormones calcitonin and vasopressin. Both mutants exhibited little or no activation of adenylate cyclase or cAMP-dependent protein kinase (cAMP-PK) in response to calcitonin, but responded to vasopressin. Analysis of calcitonin receptor function demonstrated that both mutants bound less than 9 fmol 125I-labeled salmon calcitonin/mg cellular protein, which was about 1% of parental activity (642 fmol calcitonin bound/mg). Concomitant with reduced calcitonin binding, both mutants exhibited increased vasopressin binding (greater than 272 fmol [[3H]Arg]vasopressin bound/mg) compared to parental (166 fmol bound/mg). The concentration of vasopressin for half-maximal stimulation of adenylate cyclase in both mutants was comparable to that for LLC-PK1 cells (40 pM) and hence the increased binding activity was concluded to be due to increased numbers of functional vasopressin receptors in the mutants. Somatic cell hybrids formed between each mutant and LLC-PK1 cells exhibited normal hormone binding and activation of cAMP-PK in response to both vasopressin and calcitonin. The mutations affecting receptor function in FIB6 and FIB5/N4 were accordingly concluded to be recessive. Somatic cell hybrids between FIB6 and FIB5/N4 showed no complementation of the mutant phenotype, indicating that both cell lines were affected in the same gene. In contrast, somatic cell hybrids between FIB5/N4 and the 'receptorless' mutant M18 (which lacks functional calcitonin and vasopressin receptors) exhibited approximately the same responsiveness to vasopressin and to calcitonin as LLC-PK1. Complementation between two different mutations affecting polypeptide receptor function was thus observed. The results are discussed in terms of a proposed common pathway for processing of calcitonin and vasopressin receptors.
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PMID:Complementation between LLC-PK1 mutants affected in polypeptide hormone-receptor function. 303 Jul 41

The hypothalamic paraventricular nucleus (PVN) has been implicated in a remarkable number of functions including control of pituitary-adrenocortical activity in response to stress, body fluid homeostasis, milk ejection reflex, prolactin secretion, thyroid hormone secretion, analgesia, food intake, gastrointestinal functions, cardiovascular functions, and control of pineal melatonin synthesis. Paraventricular neurons produce hormones of key importance in neuroendocrine regulation such as vasopressin (VP), oxytocin (OX), 41-residue corticotropin releasing factor (CRF), thyrotropin releasing hormone (TRH), somatostatin (SOM) and the putative prolactin releasing factor vasoactive intestinal polypeptide (VIP). Three recent advances pertinent to the organization of the PVN include: (1) the evidence that the structure of the PVN is compartmental in nature, topographically segregated cellular units seem to carry out different functions; (2) the discovery that paraventricular neurons are capable of expressing a multitude of neuromediators simultaneously, thus cellular units can be best specified by a certain combination of neuromediators; (3) evidence that the composition of the neuromediator "cocktail" in individual neurons is variable and depends on the physiological status of the animal. Hence, the PVN may be best considered as a dynamic mosaic of chemically specified subgroups of neurons. The flexibility of neurotransmitter status in paraventricular neurons may play a central role of a functional plasticity of fixed anatomical circuits.
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PMID:Dynamism of chemoarchitecture in the hypothalamic paraventricular nucleus. 304 19

The observation that suckling evokes a modest rise in serum TSH when compared with that of prolactin is inconsistent with the hypothesis that TRH serves as a hypophysiotropic mediator of this response. In the present study we attempted to provide an explanation for this discrepancy by determining whether any of a growing number of putative prolactin releasing factors could alter pituitary responsiveness to TRH. Anterior pituitaries from lactating (day 14) rats were monodispersed with trypsin, cultured for 2 days, and then incubated in the presence of medium alone or medium containing TRH, dopamine, or a combination of these secretagogues. Companion sets of cultures were incubated concurrently with either beta-endorphin, neurotensin, oxytocin, serotonin, vasoactive intestinal polypeptide, or lysine vasopressin. As expected, TRH stimulated and dopamine suppressed prolactin release. None of the substances tested except oxytocin had a significant effect on pituitary cell responsiveness to TRH or dopamine. Oxytocin had no effect on prolactin secretion when tested alone or in combination with TRH and dopamine. TRH alone stimulated TSH release by these cultures, while oxytocin and dopamine were ineffective by themselves. However, TSH secretion by cultures treated simultaneously with TRH and oxytocin could be suppressed to approximately half of that released by cells incubated with TRH alone. These results demonstrate that oxytocin attenuates TRH-induced TSH release by a direct action on pituitary cells without affecting the prolactin response. This selectivity of responsiveness imparted by oxytocin might contribute to the blunted release of TSH after suckling.
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PMID:Oxytocin attenuates TRH-induced TSH release from rat pituitary cells. 315 75


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