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

Basal adenosine 3',5'-cyclic monophosphate (cAMP) content and the modulation of its production were studied in the frog's semicircular canal epithelium. This epithelium secretes endolymph, a K(+)-rich, positively polarized fluid. The basal cAMP content measured by microradioimmunoassay was 244 +/- 14.2 fmol/structure per 5 min (n = 30). This content was increased about 8 times by 10(-5) M forskolin. Vasotocin, the frog antidiuretic hormone, increased the cAMP production by factors of 1.3 and 3.3 at concentrations of 10(-8) M and 10(-7) M, respectively. This stimulatory effect of vasotocin was blunted by the addition of alpha 2-adrenergic agonists, such as 10(-8) M-10(-5) M norepinephrine, in the presence of 10(-5) M propranolol, or 10(-5) M clonidine. Prostaglandin E2 at a concentration of 10(-8) M, which did not affect the cAMP production, did not modify the response to vasotocin. Glucagon (10(-6) M), calcitonin (10(-6) M), and parathyroid hormone (10 units/ml) did not affect the cAMP content. Prostaglandin E2 (10(-7) M) and the beta-adrenergic agonist isoproterenol (10(-6) M) stimulated the cAMP production by a factor of 1.6. These results indicate that the frog semicircular canal is a target of both vasotocin and catecholamines and that catecholamines through alpha 2-receptors modulate vasotocin-induced cAMP generation. Further, this interaction might be of physiological relevance in the modulation of ion transport in this structure.
 ...
PMID:Antidiuretic hormone stimulation of adenylate cyclase in semicircular canal epithelium. 167 38

Experiments were performed on anesthetized (chloral hydrate) Wistar rats to determine the effect of vasopressin (VP) on cerebral blood flow (CBF), cerebral oxygen consumption (CMRO2), cerebrovascular resistance (CVR), and mean arterial blood pressure (MAP) before and after V1 or V2 VP receptor blockade. Influence of synthetic V2 receptor agonist (dVDAVP) on these variables was also tested. Intracarotid administration of 5 mU VP (Pitressin, n = 15) significantly increased CBF by 28% and CMRO2 by 27% and reduced CVR by 20% of control value. Intravenous (i.v.) infusion of dEt2AVP (V1 antagonist, 15 micrograms kg-1 h-1, n = 7) did not influence the effect of VP on CBF, CMRO2, and CVR but abolished MAP increase after VP. Intravenous (i.v.) infusion of d(CH2)5[D-Ile2,Abu4] AVP (V2 antagonist, 15 micrograms kg-1 h-1, n = 8) abolished the effect of VP on CBF, CMRO2, and CVR without changing its influence on MAP. Intracarotid administration of 12.5 ng dVDAVP (n = 7) increased CBF by 43% and CMRO2 by 29% and decreased CVR by 29% of control value. MAP was not affected. The results suggest that VP-induced CBF increase is, at least partly, caused by the rise of CMRO2 and mediated by V2-like receptors.
 ...
PMID:V2-like receptors mediate cerebral blood flow increase following vasopressin administration in rats. 169 87

Arginine (AVP) and lysine vasopressin induce a weak but statistically significant increase in the water permeability of Amoeba proteus plasmalemma. Vasotocin and deaminovasopressin, which share the hydroosmotic properties of AVP on classical vertebrate systems, are without effects on Amoeba while SKF 101926, a synthetic AVP antagonist, is even more effective than the parent compound. Theophyllin and dibutyryl-cAMP do not affect AVP action on Amoeba. Lithium, oxytocin, and carbachol are also without effect. Thus, it is unlikely that either V2 (cAMP) or V1 (phosphatidylinositol choline) receptors are involved. A clear correlation has been found between the amphiphilic character of tested peptides and their effect on Amoeba water permeability. Classical amphiphilic peptides, melittin, mastoparan, and fragment 1-8 of alpha-neoendorphin, also increased water permeability in Amoeba. It is known that vasopressin can interact with artificial lipid membranes, increasing their permeability to water. We propose that amphiphilic members of the AVP family interact directly with the lipid phase of the Amoeba membrane. Their incorporation within the lipid bilayer may cause local disruptions or may create micellar water channels as shown for other amphiphilic proteins. Our observations provide a model for the early evolution of peptide hormone systems, preceding the appearance of specific membrane receptors and associated second messenger amplifying mechanisms.
 ...
PMID:The amphiphilic action of vasopressin and analogues on the plasma membrane of Amoeba proteus. 214 31

Vasopressin, a hormone secreted from the posterior lobe of the hypophysis, has endocrinological and antidiuretic effects; it contracts vessels and smooth muscles, especially intestinal smooth muscle. In the present study, we investigated the role of vasopressin (Pitressin: arginine-vasopressin) in elimination of intestinal gas on excretory urography reading. Sixty outpatients were randomly divided into six groups. In Group I, the routine procedure was employed, i.e. laxatives the previous night and NPO the morning of the examination. In Groups II to VI, different dose regimens were employed: 6 or 10 units of Pitressin was administered by subcutaneous injection 30 minutes prior to injection of a contrast medium, with or without NPO. Intestinal gas elimination was evaluated by X-ray films taken before and after injection of Pitressin. The efficacy was rated by four grades. There were no significant differences in the gas elimination or occurrence of side effects between any two groups. Younger patients seemed to respond quickly to Pitressin and good effects were obtained. These results indicate that the pretreatment for excretory urography with 6 units of Pitressin without NPO may be a safe and effective alternative method for elimination of intestinal gas, in particular for young patients.
 ...
PMID:[Clinical evaluation of vasopressin in the elimination of intestinal gas]. 228 18

Arginine vasotocin (AVT) and isotocin (IT) induced direct inhibition of adenylate cyclase activity in gill plasma membranes of the rainbow trout adapted to freshwater (FW) and seawater (SW). The maximal inhibition was obtained with 10(-11)-10(-10) M (50% inhibitory concentration approximately 10(-13) M), values in agreement with the circulating levels of AVT in trout blood. Specific V1 or V2 agonists or antagonists (with reference to vasopressin) were used to define the specificity of the neurohypophysial peptide receptors involved in this inhibition. The V1 agonist [Phe2,Orn8]vasotocin ([Phe2]OVT) inhibited the basal and glucagon-stimulated adenylate cyclase activity, and this effect in SW (20%) was twice more than in FW (10%). The V2 agonist 1-deamino[Val4,Arg8]-vasopressin (dVDAVP), however, produced a stimulation that was of the same amplitude (10%) in both media. The V1 antagonist [(1-beta-mercapto-beta-beta-cyclopentamethylenepropionic acid), 1-(O-ethyl)Tyr2,Orn8]vasotocin (d(CH2)5[Tyr(Et)2]OVT) totally reversed the AVT- or IT-induced inhibition of basal or glucagon-stimulated cyclase activity, whereas the V1/V2 antagonist [(1-beta-mercapto-beta-beta-cyclopentamethylene propionic acid), 1-(O-ethyl)D-Tyr2,Val4,Arg8]vasopressin (d(CH2)5[D-Tyr(Et)2]-VAVP) (previously used as V2 antagonist in amphibians) had no such effect. When active, all analogues had their maximal activity at 10(-11)-10(-10) M (50% maximal activity approximately 10(-13) M), as observed with the natural peptides. These results, together with our previous observations, point to the gill epithelium as a direct target organ for neurohypophysial peptides and suggest that the hormone receptors involved in fish belong predominantly, if not exclusively, to a new type that we propose to designate as fish neurohypophysial hormone (NHF) receptors while awaiting further characterization.
 ...
PMID:Evidence for presence of a new type of neurohypophysial hormone receptor in fish gill epithelium. 230 44

Management of acute gastrointestinal bleeding follows a logical sequence of steps. The first priority is to assess the magnitude of blood loss and resuscitate the patient. The patient history and nasogastric aspiration can help localize the source of bleeding to the upper tract or lower tract. Treatment of suspected upper gastrointestinal bleeding is usually empirical and consists of histamine 2 blockers (or sucralfate [Carafate]) or antacids. Diagnosis of the specific bleeding site is based on the severity, activity, and nature of the bleeding. Endoscopic and radiographic techniques may be useful. Intravenous vasopressin (Pitressin) therapy and endoscopic sclerotherapy are important in the management of variceal hemorrhage. Therapeutic endoscopic techniques are being used more often to manage nonvariceal bleeding as well.
 ...
PMID:Acute gastrointestinal bleeding. A logical approach to management. 231 58

Rats with mammillary electrolytic lesions show a strong polydipsia and polyuria. This over-consumption may be primary or secondary to the polyuric effect. In this regard, mammillary lesioned rats excrete a greater amount of urine compared with control animals when matched in daily water consumption (partial water deprivation). Moreover, this abnormal water intake is significantly reversed by treatment with Pitressin, a vasopressin analogue. These results suggest that the polydipsia may be determined by the urinary water loss. However, when subjected to the bilateral ureter ligation, the experimental animals still outdrink the control ones, thus also suggesting a primary component of the polydipsia under study. The possible explanation of these components in relation to the mammillary polydipsia is discussed.
 ...
PMID:[Primary/secondary characteristics of polydipsia induced by electrolytic lesion of the mammillary bodies]. 250 36

Vasotocin (AVT) analogues with tyrosine or phenylalanine in position 9, i.e., [9-tyrosine]AVT, [2-phenylalanine,-9-tyrosine]AVT, and 1-desamino[9-(p-aminophenylalanine)]AVT, were synthesized by the solid-phase method. These compounds showed a high biological activity in the hydroosmotic toad bladder assay. Using the chemically reactive functional groups on tyrosine and p-aminophenylalanine in position 9, we prepared iodinated, photoreactive, and affinity ligands, i.e., [2-phenylalanine,9-(iodotyrosine)]AVT, 1-desamino[9-(p-azidophenylalanine)]AVT, and 1-desamino[9-(biotinylphenylalanine)]AVT, respectively. Half-maximal hydroosmotic responses (ED-50 values) were obtained with 2.5 X 10(-9) M for the iodinated analogue, with 0.9 X 10(-10) M for the photoaffinity analogue, and with 1.2 X 10(-8) M for the biotinyl analogue. The hydroosmotic activity of the biotinyl analogue was reversed following addition of avidin, whereas the photoaffinity analogue induced a persistent response following UV irradiation that was not reversed upon repeated and prolonged periods of washout. These analogues of vasotocin are the most potent that have been synthesized to date, and they should serve as useful probes in the isolation and characterization of vasotocin receptors in toad bladders and tissues from other species that use vasotocin as an antidiuretic/pressor principle. The photoaffinity and biotinyl analogues had a rat antidiuretic activity of 66 and 40 units/mg, respectively. These compounds are, therefore, also suitable for the isolation of V-2 vasopressin receptors from mammalian tissues.
 ...
PMID:Photoaffinity, biotinyl, and iodo analogues as probes for vasotocin receptors. 281 Mar 31

Arginine vasotocin (AVT) was isolated from extracts of sea lamprey pituitary glands (Petromyzon marinus). The amino acid sequence Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Arg-Gly-NH2 is identical to the molecule isolated from teleosts and tetrapods. The total yield was estimated to be 9.6 pmol per gland. No evidence could be found for the existence of a second neurohypophyseal nonapeptide in the lamprey pituitary.
 ...
PMID:Arginine vasotocin from the pituitary gland of the lamprey (Petromyzon marinus): isolation and amino acid sequence. 337 48

The postnatal developmental course of the enhanced OT serum level of the vasopressin-deficient (homozygous) Brattleboro rat was investigated radioimmunochemically together with the response to treatment with Pitressin tannate. Compared with heterozygous Brattleboro (control) pups, in which serum OT appeared to have an adult value from birth onwards (about 10 pmol/l), homozygous rats had approximately 2-fold enhanced OT serum level throughout early development. Between day 55 and adulthood the levels of OT rose further to 40-50 pmol/l. A 3-day treatment with Pitressin tannate both in the period before or after the age (day 16) at which the polyuria of the homozygous Brattleboro mutant can be revealed, failed to reduce the serum OT. It was therefore concluded that the high OT serum levels in the vasopressin-deficient Brattleboro rat are not induced by osmotic imbalance, but probably originates from functional teratological aspects of the mutation.
 ...
PMID:Elevated serum oxytocin of the vasopressin-deficient Brattleboro rat is present throughout life and is not sensitive to treatment with vasopressin. 338 37


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>