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)

Peptides can be transported across the blood-brain barrier by saturable transport systems. One system, characterized with radioactively labeled Tyr-MIF-1 (Tyr-Pro-Leu-Gly-amide), is specific for some of the small peptides with an N-terminal tyrosine, including Tyr-MIF-1, the enkephalins, beta-casomorphin, and dynorphin (1-8). Another separate system transports vasopressin-like peptides. The choroid plexus has at least one system distinguishable from those above that is capable of uptake and possibly transport of opiate-like peptides. The possibility of saturable transport of other peptides has been investigated to a varying degree. Specificity, stereo-specificity, saturability, allosteric regulation, modulation by physiologic and pharmacologic manipulations, and noncompetitive inhibition have been demonstrated to occur in peptide transport systems and suggest a role for them in physiology and disease.
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PMID:Saturable transport of peptides across the blood-brain barrier. 330 36

The presence of vasopressin receptors of the V1 (vascular) type and of oxytocin receptors in the rat kidney was investigated using an autoradiographical approach. Rat kidney sections were incubated with tritiated vasopressin ([3H]vasopressin, 1.5 nM) or oxytocin ([3H]oxytocin, 3 nM). The ligand selectivity of the [3H]vasopressin binding sites detected was deduced from competition experiments using one selective unlabeled ligand for V2 (antidiuretic) vasopressin receptors (1-deamino-[8-D-arginine]-vasopressin, dDAVP) and one selective unlabeled ligand for V1 receptors (des-glycineamide-[1-(beta-mercapto-beta,beta-cyclopentamethylene propionic acid]-arginine vasopressin, des(Gly(NH2)9d(CH2)5-AVP). Specific and dense [3H]vasopressin labeling was observable in the medullopapillary and cortical portions of the kidney. Specific [3H]vasopressin binding in the cortex was insensitive to the V1-selective ligand, des(Gly(NH2)9d(CH2)5-AVP, but was inhibited by dDAVP. Glomerular structures identified as such by microscopical observation of the kidney sections were specifically labeled with [3H]oxytocin and [125I]-SAR1-angiotensin II but not with [3H]vasopressin. It is concluded that V1 receptors which have been evidenced on mesangial cells in culture are not expressed in a detectable quantity on mesangial cells in situ. The specific [3H]oxytocin binding to glomeruli might reflect the presence on glomerular structures of oxytocin receptors involved in the effects of the hormone on renal hemodynamics, and possibly in some of the effects ascribed to vasopressin.
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PMID:Autoradiographic localization of vasopressin and oxytocin binding sites in rat kidney. 339 84

Degradation of LHRH and [D-Ser(tBu)6,des-Gly-NH10(2)]LHRH ethylamide (LHRH-A), during incubation with high-speed supernatants of rat testes, as assessed by reversed-phase (RP)-HPLC fractionation of the iodinated peptides and by radioimmunoassays for LHRH or LHRH-A, was principally due to a neutral 43 000 Da peptidase with apparent Km values at 25 degrees C of 0.15 microM for LHRH and 1.19 microM for LHRH-A. The peptidase was inhibited by sulphydryl reagents, TLCK, 1,10-phenanthroline, EDTA, bacitracin, other LHRH analogues, oxytocin, [Lys8]vasopressin and somatostatin. It was predomantly located in seminiferous tubule supernatants (98% of recovered activity), with much lower levels in interstitial fluid (2%), interstitial tissue or testicular particulate fractions (less than 0.8%). Extracts of cultured immature Sertoli cells produced LHRH- and LHRH-A-degradation profiles, as assessed by RP-HPLC, that were identical to those produced by testicular supernatants. Similar levels of peptidase activity/mg protein were observed in immature and adult rat testes. These studies indicate that the principal LHRH-peptidase in the rat testis is produced by cells of the seminiferous epithelium, chiefly the Sertoli cell, and may play an important role in regulating the activity of LHRH and other peptide hormones in the testis.
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PMID:Degradation of luteinizing hormone-releasing hormone (LHRH) and an LHRH agonist by the rat testis. 351 17

Vasoactive peptides contain a high proportion of proline residues which make them resistant to hydrolysis by many peptidases. However, post proline cleaving enzyme (PPCE; EC 3.4.21.26), a proline specific endopeptidase which specifically hydrolyzes internal peptide bonds on the carboxyl side of proline residues, has been shown to inactivate numerous vasoactive peptides including angiotensins, kinins, substance P, vasopressin and oxytocin. In order to determine whether PPCE could be involved in vascular metabolism of vasoactive peptides, we carried out localization and characterization studies of PPCE-like activity in hog aorta and mesenteric artery. PPCE was assayed fluorometrically at pH 7.0 using the specific PPCE substrate CBZ-Gly-Pro-4-methyl-coumarinylamide. The subcellular distribution of vascular PPCE was essentially the same as that of the cytosolic marker enzyme lactic dehydrogenase (LDH). PPCE was enriched six-fold in the cytosolic fraction (11.4 +/- 2.7 units/mg) and unlike the plasma membrane-bound proline specific exopeptidase dipeptidyl-(amino)peptidase IV (DAP IV; EC 3.4.14.5), little or no activity could be detected in the microsomal or plasma membrane fractions. Similar to PPCE characterized from other sites, vascular PPCE was stabilized and activated by dithiothreitol and EDTA, and inhibited by DFP, p-chloromercuriphenyl sulfonic acid, L-1-tosylamido-2-phenylethylchloromethyl ketone, Cu++, Ca++, and Zn++. Vascular PPCE was unaffected by inhibitors of trypsin and kallikrein (Aprotinin, ABTI), aminopeptidase M (bestatin, amastatin), neutral endopeptidase (phosphoramidon), angiotensin I converting enzyme (captopril) or carboxypeptidase N (MERGETPA). These data demonstrate that PPCE is present in vascular endothelium and/or smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vascular, post proline cleaving enzyme: metabolism of vasoactive peptides. 354 18

Rats were trained on a peak-interval timing procedure in which auditory, tactile, and visual stimuli signaled 3 different fixed-interval schedules (15, 30, and 60 s) that were presented simultaneously in a hierarchical fashion. Administration of vasopressin metabolite neuropeptide [pGlu-Asn-Cys(Cys)-Pro-Arg-Gly-NH2, 0.3 microgram/kg i.p.] had two main effects on performance. With repeated exposure the temporal criterion for each of the intervals shifted leftward on the time scale in a proportional manner, and the probability of attention to each of the intervals increased proportionally. The conclusion is that vasopressin metabolite neuropeptide facilitates simultaneous temporal processing by increasing the speed of mental processes involved in memory storage and divided attention. These results indicate that a major metabolite of arginine vasopressin that is devoid of endocrine and pressor activity can produce facilitation of cognitive processes in animals.
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PMID:Vasopressin metabolite neuropeptide facilitates simultaneous temporal processing. 356 8

A bovine pineal acid extract displays a vasotocin-like bioactivity in several bioassays, and is recognized by antibodies against the Pro-Arg-Gly-amide ending common to vasopressin and vasotocin. By using molecular sieve filtration and reversed-phase HPLC, a vasopressin- and oxytocin-like peptide was isolated from this pineal preparation, while no evidence for a vasotocin-like peptide was obtained. The isolated neuropeptides contain a modified amino acid at position 2. This structural difference with authentic pituitary vasopressin and oxytocin may alter their biological and immunological properties, which have been interpreted as vasotocin-like, and thus underlies the controversy concerning the existence of vasotocin in the mammalian pineal gland.
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PMID:Modified forms of vasopressin and oxytocin in a bovine pineal preparation. 358 72

The vasopressin-oxytocin family of peptides is of very ancient lineage, found in organisms as diverse as hydra and man. Although these peptides have been intensively studied in vertebrates, the presumably more extensive invertebrate series was defined primarily by immunological methods. In this report, we describe the purification and structures of two peptides of the vasopressin-oxytocin family from molluscs ("Conopressins"), which were found in the venom of fish-hunting marine snails of the genus Conus. The biological activity observed when the two snail peptides are injected intracerebrally into mice is very similar to that elicited by the vertebrate neurohypophyseal hormones and presumably reflects their actions upon a common receptor in the brain. The sequences of the purified peptides reveal unique features not found in the vertebrate peptide series, most notably an additional positive charge. These are the first members of the invertebrate series of the vasopressin-oxytocin family to be characterized biochemically. The sequences of these peptides are: from Conus geographus venom, Lys-conopressin-G, Cys-Phe-Ile-Arg-Asn-Cys-Pro-Lys-Gly-NH2; and from Conus striatus venom, Arg-conopressin-S, Cys-Ile-Ile-Arg-Asn-Cys-Pro-Arg-Gly-NH2.
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PMID:Invertebrate vasopressin/oxytocin homologs. Characterization of peptides from Conus geographus and Conus straitus venoms. 368 Feb 28

A brain to blood carrier-mediated transport system for arginine vasopressin (AVP) was investigated in mice after intraventricular injection of iodinated AVP and varying amounts of unlabeled material or candidate inhibitors. Residual activity in the brain detected after decapitation was used as the main determinant of transport activity. The half-time disappearance of iodinated AVP from the brain was 12.4 min, the Vmax was 1.41 nmol/g-min, and the apparent Km was 28.7 nmol/g. A 30-nmol dose of AVP, mesotocin, arginine vasotocin, pressinoic amide, pressinoic acid, tocinoic acid, and lysine vasotocin, but not oxytocin, lysine vasopressin, AVP free acid, tocinoic amide, Tyr-MIF-1, or cyclo Leu-Gly, significantly (P less than 0.05) inhibited the transport of iodinated AVP out of the brain. The 30 nmol dose of AVP had no effect on the transport of iodide or iodotyrosine out of the brain. High-performance liquid chromatography showed that 59.2% of the radioactivity found in the blood 2 min after an i.c.v. injection of labeled AVP eluted at the same position as labeled AVP compared with 68.8% of radioactivity eluting at that position after material was infused i.v. for 2 min. This indicates that intact peptide is transported across the blood-brain barrier and that most of the degradation of AVP occurs during circulation in the blood. Calculations based on the appearance of radioactivity in the periphery showed that 56.2% of the material injected centrally would have been transported into the periphery by 10 min. This appearance of material in the periphery was inhibited by the simultaneous injection of an excess of unlabeled peptide. Water loading significantly decreased the brain to blood transport rate of AVP by 40%. It is concluded that a saturable system exists for brain to blood transport of AVP and some structurally similar peptides.
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PMID:Carrier-mediated transport of vasopressin across the blood-brain barrier of the mouse. 369 15

A chemical method has been established for the detection of carboxyl-terminally amidated peptides in tissue extracts. Tissue was homogenized in an acidic medium designed to solubilize peptides while precipitating high-molecular-weight protein. The homogenate supernatant was in turn subjected to reversed-phase extraction with C18 Sep-Pak cartridges. The eluates were fractionated by reversed-phase high-performance liquid chromatography (RP-HPLC). Individual fractions were exhaustively digested with thermolysin, derivatized with phenylisothiocyanate (PITC), and then subjected to ethyl acetate extraction under basic conditions. The phenylthiocarbamyl (PTC)-amino acid amide derivatives were selectively taken up into the organic phase, while the other digestion products remained in the aqueous phase. The organic phase was analyzed by RP-HPLC on a Pico-Tag amino acid analysis column, monitoring eluates at 254 nm. PTC-amino acid amides were identified and quantitated by comparing their elution positions and peak areas, respectively, with those of standards. Their identities were confirmed by amino acid analysis, following hydrolysis with hydriodic acid. The technique was applied to extracts of bovine posterior pituitaries and a human medullary thyroid carcinoma. Vasopressin (-Leu-Gly-amide), oxytocin (-Gly-amide), Lys1 gamma 1-melanotropin (-Phe-amide), and various acetylated and non-acetylated forms of alpha-melanotropin (-Val-amide) were identified in the posterior pituitary extract. Various forms of calcitonin (-Val-Gly-Ala-Pro-amide) were detected in the tumour extract. For vasopressin and calcitonin the thermolytic digest resulted in di- and tetra-peptides, respectively, reflecting thermolytic cleavage at more favoured sites.
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PMID:Use of Pico-Tag methodology in the chemical analysis of peptides with carboxyl-terminal amides. 373 29

The peptides vasopressin-Gly and vasopressin-Gly-Lys-Arg occur as part of the sequence of the vasopressin-neurophysin precursor molecule and may be released from the hypothalamus and/or pituitary. [8-Lysine]-vasopressin-Gly (LVP-Gly) and [8-lysine]-vasopressin-Gly-Lys-Arg were administered i.v. to conscious, water-diuretic rats. The renal effects of the peptides were assessed by comparison with the actions of [8-lysine]-vasopressin (LVP) which was administered to separate groups of rats. LVP-Gly and LVP-Gly-Lys-Arg were weakly antidiuretic. LVP-Gly-Lys-Arg was the more potent of the two peptides, but on a molar basis it only had about 10% of the antidiuretic activity of LVP. LVP-Gly and LVP-Gly-Lys-Arg at 10 pmol/h per 100 g body weight (equivalent to the maximal antidiuretic dose of LVP) slightly decreased (P less than 0.001) urine flow without causing significant changes in urine osmolality. LVP (10 pmol/h per 100 g body weight) promoted a marked natriuresis (P less than 0.001) but LVP-Gly and LVP-Gly-Lys-Arg were not natriuretic, even at the dose which was markedly antidiuretic (100 pmol/h per 100 g body weight). Osmolal output decreased at all doses during administration of the extended peptides, but was not significantly changed in the control group or by LVP. Inulin clearance was decreased by about 30% during administration of both LVP and LVP-Gly-Lys-Arg at 100 pmol/h per 100 g body weight.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of vasopressin-glycine and vasopressin-glycine-lysine-arginine on renal function in the rat. 395 May 30


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