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)

Endopeptidase-2, the second endopeptidase in rat kidney brush border [Kenny & Ingram (1987) Biochem. J. 245, 515-524] has been further characterized in regard to its specificity and its contribution to the hydrolysis of peptides by microvillar membrane preparations. The peptide products were identified, after incubating luliberin, substance P, bradykinin and angiotensins I, II and III with the purified enzyme. The bonds hydrolysed were those involving a hydrophobic amino acid residue, but this residue could be located at either the P1 or P1' site. Luliberin was hydrolysed faster than other peptides tested, followed by substance P and bradykinin. Human alpha-atrial natriuretic peptide and the angiotensins were only slowly attacked. Oxytocin and [Arg8]vasopressin were not hydrolysed. No peptide fragments were detected on prolonged incubation with insulin, cytochrome c, ovalbumin and serum albumin. In comparison with pig endopeptidase-24.11 the rates for the susceptible peptides were, with the exception of luliberin, much lower for endopeptidase-2. Indeed, for bradykinin and substance P the ratio kcat./Km was two orders of magnitude lower. Since both endopeptidases are present in rat kidney microvilli, an assessment was made of the relative contributions to the hydrolysis of luliberin, bradykinin and substance P. Only for the first named was endopeptidase-2 the dominant enzyme; for bradykinin it made an equal, and for substance P a minor, contribution.
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PMID:The metabolism of neuropeptides. Hydrolysis of peptides by the phosphoramidon-insensitive rat kidney enzyme 'endopeptidase-2' and by rat microvillar membranes. 246 6

We have previously reported that cultured monolayers of folliculo-stellate cells (FC) of adenohypophysial pars tuberalis (PT) and pars distalis (PD) origin express morphological and electrical properties typical of ion and fluid transporting epithelia. The objective of the present study was to examine whether cells expressing similar transport properties exist also in the pars intermedia (PI), an area of the adenohypophysis very poorly vascularized, where a cell type expressing such functions would be expected to play an especially significant role in the local regulation of the interstitial fluid content and circulation. Enzymatically and mechanically dispersed bovine pars intermedia fragments yield monolayers of polygonal, contact inhibited cells which rapidly develop domes. Such cells exhibit morphological features and growth properties very similar or identical to those expressed by cells previously identified af FC cells in PD and PT cultures. Similarly to their counterparts in the PD and PT, the PI FC display a potential difference and a resistance when mounted in Ussing chambers. Isoproterenol, prostaglandin E2, bradykinin and lysine vasopressin are able to stimulate active ion transport across FC monolayers. These data indicate that the PI contains ion transporting FC and suggest important local regulatory functions for these cells.
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PMID:Regulation of ion transport in hypophysial pars intermedia follicular cell monolayers. 246 71

To aid in characterizing adenosine receptors in renal cells, primary cultures of rabbit cortical collecting tubule (RCCT) cells were infected with an adenovirus 12-simian virus 40 hybrid, resulting in a continuous cell line. The cells, designated RCCT-28A, retained their epithelial morphology and reacted with a monoclonal antibody specific for rabbit collecting tubule. Adenosine 3',5'-cyclic monophosphate (cAMP) accumulation was stimulated by vasopressin (AVP), isoproterenol, prostaglandin E2 (PGE2), calcitonin, parathyroid hormone, and a potent adenosine A1- and A2-receptor agonist, 5'-N-ethylcarboxamidoadenosine (NECA). A more selective adenosine A1-receptor agonist, N6-cyclohexyl adenosine (CHA) inhibited basal and AVP-stimulated cAMP accumulation. Cytosolic free calcium was transiently elevated by bradykinin, PGE2, NECA, and CHA. To examine the mechanism by which adenosine analogues increase intracellular free calcium, phosphoinositide (PI) turnover was assessed in the 28A cells after labeling with myo-[3H]inositol. NECA and CHA increased [3H]inositol phosphate formation with an approximate half-maximal effective concentration of 0.1 microM for both analogues. The increase in PI turnover was blocked by the selective adenosine A1-receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine and pretreatment of the 28A cells with pertussis toxin. These results suggest that adenosine analogues increase cytosolic free calcium by stimulating PI turnover.
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PMID:Adenosine-sensitive phosphoinositide turnover in a newly established renal cell line. 247 75

Changes in intracellular free Ca2+ concentration [( Ca2+]i) produced by growth factors and mitogens have been studied using aequorin-loaded Swiss 3T3 cells. Decreasing free Ca2+ in the external medium by using EGTA had no significant effect on the increase in [Ca2+]i produced by vasopressin, bradykinin, bombesin or prostaglandin E2, but reduced the increase in [Ca2+]i produced by platelet derived growth factor (PDGF) by 58%, by prostaglandin E1 44% and by prostaglandin F2 alpha 47%. The dihydropyridine Ca2+-channel antagonist nifedipine at 10 microM inhibited the [Ca2+]i response to PDGF by 41% in both the presence of and in the absence of external Ca2+. Methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl) pyridine-5-carboxylate (BAY K8644), a Ca2+-channel agonist, at 10 microM produced an increase in [Ca2+]i and decreased the [Ca2+]i response to PDGF by 39%. Nifedipine did not block 45Ca2+ uptake or release by inositol 1,4,5-trisphosphate in saponin-permeabilized Swiss 3T3 fibroblasts but BAY K8644 inhibited 45Ca2+ release by inositol 1,4,5-trisphosphate. The results suggest that the increase in [Ca2+]i caused by PDGF in Swiss 3T3 fibroblasts is due to the influx of external Ca2+ through dihydropyridine sensitive Ca2+ channels, as well as release of internal Ca2+.
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PMID:Contribution of external and internal Ca2+ to changes in intracellular free Ca2+ produced by mitogens in Swiss 3T3 fibroblasts: the role of dihydropyridine sensitive Ca2+ channels. 247 47

The neuropeptides vasopressin, bradykinin, cholecystokinin, galanin, neurotensin and gastrin-releasing peptide stimulate rapid, transient increases in cytosolic Ca2+ in small cell lung cancer cell lines at nanomolar concentrations. Responsiveness to individual peptides is heterogeneous among the diverse cell lines, but the ability to respond to regulatory peptides is a general phenomenon. Peptide responses demonstrate homologous desensitisation and are blocked by ligand-specific antagonists, indicating that they are mediated by distinct receptors. Many neuropeptides are also secreted by small cell lung cancer. Here we suggest that multiple autocrine and paracrine interactions regulate its growth.
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PMID:Multiple neuropeptides mobilise calcium in small cell lung cancer: effects of vasopressin, bradykinin, cholecystokinin, galanin and neurotensin. 247 33

While screening neuropeptides for activity as growth factors we have found that bradykinin is a mitogen for Swiss 3T3 cells. It acts synergistically with insulin, and maximal effect is obtained at 10 nM. It acts through a distinct receptor, characterized as a B2 subtype using bradykinin analogues. The neuropeptides bombesin and vasopressin are also potent mitogens for Swiss 3T3 cells. The substance P antagonists [DArg1, DPro2, DTrp7,9, Leu11] substance P and [DArg1, DPhe5, DTrp7,9, Leu11]substance P are inhibitors of DNA synthesis stimulated by both bombesin and vasopressin. In the present study they were found also to inhibit bradykinin-induced mitogenesis. In contrast, the ligand-specific antagonists [Leu13-psi(CH2NH)Leu14]bombesin, [Pmp1, OMeTyr2, Arg8]vasopressin and [DArg0, Hyp3, Thi5,8, DPhe7]bradykinin showed no cross-inhibition with each others receptors. We propose therefore that the receptors for the mitogenic neuropeptides bombesin, vasopressin, and bradykinin can interact with two classes of antagonist, one recognizing the ligand binding site (e.g., [Leu13-psi(CH2NH)Leu14]bombesin) and the other recognizing a common domain shared by the three receptors (e.g., [DArg1, DPhe5, DTrp7,9, Leu11]substance P).
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PMID:Two classes of antagonist interact with receptors for the mitogenic neuropeptides bombesin, bradykinin, and vasopressin. 248 37

High molecular weight (500 kDa) dextran sulfate (DXS) inhibited the release of Ca2+ induced by myoinositol 1,4,5-trisphosphate from non-mitochondrial stores of saponin-permeabilized Swiss 3T3 fibroblasts with an IC50 of 20 micrograms/mL. Low molecular weight (5 kDa) DXS did not have this effect. DXS was more inhibitory than heparin, which in the same system had an IC50 of 62 micrograms/mL. DXS also produced a small inhibition of Ca2+ release by arachidonic acid and GTP but did not affect Ca2+ release by 4-bromo A23187 or halothane. The transient increase in intracellular free Ca2+ concentration ([Ca2+]i) in intact Swiss 3T3 cells caused by platelet-derived growth factor was completely inhibited by 100 micrograms/mL of DXS, but DXS had no effect on the [Ca2+]i increase caused by bradykinin or vasopressin. The specific binding of platelet-derived growth factor, but not of bradykinin or vasopressin, to Swiss 3T3 fibroblasts was decreased by DXS. The effect of DXS in decreasing growth-factor mediated increases in [Ca2+]i may be mediated by an effect on the binding of growth factor to its receptor. An effect of DXS on the intracellular release of Ca2+ by second messengers to decrease changes in [Ca2+]i, however, cannot be ruled out.
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PMID:High molecular weight dextran sulfate inhibits intracellular Ca2+ release and decreases growth factor-induced increases in intracellular free Ca2+ in Swiss 3T3 fibroblasts. 248 58

Tritiated phosphatidyl choline (1-palmitoyl,2-[3H]palmitoyl or 1-stearoyl,2-[3H]arachidonyl) is taken up unchanged by the isolated perfused rabbit heart. Isoproterenol, vasopressin or A23187 enhanced the output of tritium in these hearts, whereas bradykinin, angiotensin II or acetylcholine had no effect. These data demonstrate that [3H]phosphatidyl choline is incorporated directly into a phospholipid pool that is accessible to some, but not all, hormonally stimulated lipases. In hearts labeled with 1-stearoyl,2-[3H]arachidonyl phosphatidyl choline, the radioactivity released by isoproterenol consisted of free fatty acid and lysophosphatidyl choline, indicating that isoproterenol stimulates both phospholipase(s) A1 and A2. Vasopressin and A23187 increased the release of free fatty acid, but not lysophosphatidyl choline, suggesting that these agents stimulate only phospholipase A2.
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PMID:Uptake and hormonally induced hydrolysis of [3H]phosphatidyl choline in the isolated rabbit heart. 249 94

Insulin and various growth factors (epidermal growth factor (EGF), insulin-like growth factor, fibroblast growth factor, and transforming growth factor alpha), which fail to modify the resting [Ca2+]i in PC12 rat pheochromocytoma and SKNBE human neuroblastoma cells when administered alone, became capable of inducing [Ca2+]i increases when administered a few (4-20) min after another agent, bradykinin. The latter peptide, working through a B2 receptor, caused hydrolysis of polyphosphoinositides and a large, biphasic [Ca2+]i transient (an initial (1-2 min) spike, originated primarily from intracellular stores, followed by a steady-state elevation dependent on Ca2+ influx). Priming by bradykinin of the growth factor effects was quickly dissipated by the addition of a B2 blocker. Activation of other receptors coupled to polyphosphoinositide hydrolysis: muscarinic and purinergic (in PC12 and SKNBE cells); bombesin and vasopressin receptors (in Swiss 3T3 cells), was without effect in priming. Bradykinin-primed, growth factor-induced [Ca2+]i rises in PC12 cells appeared after a 20-30-s delay; they were relatively small, but persistent; their concentration dependence was similar to that of other effects of the factors; and they included both release of Ca2+ from intracellular stores and stimulation of Ca2+ influx, preceded (in PC12 cells) by a transient increase of polyphosphoinositide hydrolysis. Thus the effect of growth factors (possibly dependent on the tyrosine kinase activity of their receptors) consisted in the reinforcement of the transmembrane signaling at B2 receptors. This is the first direct demonstration of a [Ca2+]i rise induced by insulin and insulin-like growth factor-I, and of such an effect of EGF in cell types endowed with a small number of specific EGF receptors.
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PMID:Reinforcement of signal generation at B2 bradykinin receptors by insulin, epidermal growth factors, and other growth factors. 253 35

The purpose of the present study was to examine the tissue selectivity of several [Arg1-D-Phe7]-substituted analogs of bradykinin. Unlike D-Arg-[Hyp3-D-Phe7]-bradykinin (NPC567), which antagonizes bradykinin-induced contractions both in rat isolated uterus and guinea pig ileum, [D-Nal1-Thi5,8-D-Phe7]-bradykinin (NPC573) was active only in uterine smooth muscle. Binding studies revealed that, unlike several [D-Phe7]-substituted analogs, including NPC567, NPC573 competed with radiolabeled bradykinin neither at receptors in uterus nor ileum. Moreover, no [Arg1-D-Phe7]-substituted analog competed with bradykinin binding in guinea pig ileum, suggesting that these agents, which inhibit uterine but not ileal contractions to bradykinin, may not be bradykinin receptor antagonists. NPC573 inhibited [Arg8]-vasopressin-induced contraction of the uterus more potently than it did bradykinin, although NPC573 (and other [Arg1-D-Phe7]-substituted analogs tested) did not inhibit binding of a vasopressin antagonist either in uterus or liver membranes. We therefore suggest that [Arg1-D-Phe7]-substituted analogs of bradykinin inhibit contractions of uterine smooth muscle by a mechanism other than receptor antagonism. In addition, the tissue selectivity of these agents suggests that the mechanisms underlying bradykinin's contractile effect in uterus are different than in intestinal smooth muscle.
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PMID:[Arg1-D-Phe7]-substituted bradykinin analogs inhibit bradykinin- and vasopressin-induced contractions of uterine smooth muscle. 253 8


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