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)

Solution methods, using N-hydroxysuccinimide esters, were used to synthesize [Glu(NHNH2)4] oxytocin and [Glu(NHNH2)4, Lys8] vasopressin. In these analogs of neurohypophyseal hormones, the side-chain carboxamide function of a glutamine residue is formally replaced by a hydrazide group at position 4. The hormone analogs were assayed for uterototonic activity, milk ejection activity, antidiuretic activity, and rat pressor activity. The specific biological activities of the oxytocin and vasopressin analogs were decreased compared to the respective parent hormones in all assay systems.
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PMID:Synthesis and biological activities of oxytocin and lysine vasopressin analogs containing glutamic acid gamma-hydrazide in position 4. 261 36

The purpose of this article is to describe briefly the methods by which the intra-mitochondrial volume may be measured both in vitro and in situ, to summarise the mechanisms thought to regulate the mitochondrial volume and then to review in more detail the evidence that changes in the intra-mitochondrial volume play an important part in the regulation of liver mitochondrial metabolism by glucogenic hormones such as glucagon, adrenaline and vasopressin. It will be shown that these hormones cause an increase in matrix volume sufficient to produce significant activation of fatty acid oxidation, respiration and ATP production, pyruvate carboxylation, citrulline synthesis and glutamine hydrolysis. These are all processes activated by such hormones in vivo. I will go on to demonstrate that the increase in matrix volume is brought about by an increase in mitochondrial [PPi]. This is able to stimulate K+ entry into the matrix, perhaps through an interaction with the adenine nucleotide translocase. The rise in matrix [PPi] is a consequence of an increase in cytosolic and hence mitochondrial [Ca2+] which inhibits mitochondrial pyrophosphatase. In the final section of the review I provide evidence that changes in mitochondrial volume may be important in the responses of a variety of tissues to hormones and other stimuli. I write as a metabolist with a working knowledge of bioenergetics rather than the converse, and this will certainly be reflected in the approach taken. If I cause offence to any dedicated experts in the field of bioenergetic by my ignorance or lack of understanding of their studies I can only offer my apologies and ask to be corrected.
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PMID:The regulation of the matrix volume of mammalian mitochondria in vivo and in vitro and its role in the control of mitochondrial metabolism. 264 40

The presence of several naturally occurring amino acids in the serosal bath of toad urinary bladder significantly alters the hydrosmotic response of this tissue to vasopressin. We found that histidine, glutamate, and lysine increase vasopressin-stimulated water flow by 75%, 60%, and 43%, respectively. In contrast, alanine did not alter vasopressin-stimulated water flow, whereas glutamine decreased it by 25%. The effect of each amino acid represents intracellular events because their effects on theophylline-stimulated water flow were similar to those found with vasopressin. However, the site of action of amino acids varied, with some operating at steps before and others at steps after cyclic AMP generation. The fact that the metabolically inactive D-histidine and D-glutamate are as effective as their metabolically active L-counterparts suggests that the action of amino acids depends upon some physicochemical properties of their molecules. The ability of amino acids to influence the hydrosmotic effects of vasopressin was shown to be independent of prostaglandin generation, ionic composition, and molecular charge. In the case of histidine, we were able to obtain some understanding of the mechanism responsible for its action. We first showed that the effect of histidine does not depend upon its metabolism. In addition to D-histidine being as effective as the metabolically active L-histidine, we also showed that histidine is effective when its metabolism is abolished by low ambient temperature and also when its incorporation into proteins was prevented by cycloheximide. These findings suggest that histidine operates through some physicochemical property localized on its molecule. We were able to show that this property resides on the imidazole part of histidine. Imidazole, similar to histidine, increases vasopressin-stimulated water flow. Methylation of histidine on the imidazole ring completely abolished its effectiveness in increasing vasopressin-stimulated water flow. In contrast, methylation of histidine at the side chain increased vasopressin action similar to that found for histidine. We provide evidence that the physicochemical property of the imidazole ring of histidine is that of chelating Zn++ intracellularly, and that the intracellular site of action of histidine is closely linked to microtubules formation and/or action.
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PMID:Importance of amino acids on vasopressin-stimulated water flow. 286 87

In hepatocytes, urea synthesis from glutamine is independent of added ornithine, even when rates are high after stimulation of glutamine metabolism by dibutyryl cyclic AMP, phenylephrine or vasopressin. Incubation with glutamine increases tissue [ornithine]. The increases parallel those of [N-acetylglutamate] under different conditions. The ornithine requirement of urea synthesis increases with increasing supply of ammonia. A function of the unique, highly regulated, glutaminase of liver may be to regulate ornithine synthesis.
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PMID:The ornithine requirement of urea synthesis. Formation of ornithine from glutamine in hepatocytes. 303 Feb 72

Glutamine stimulated glycogen synthesis and lactate production in hepatocytes from overnight-fasted normal and diabetic rats. The effect, which was half-maximal with about 3 mM-glutamine, depended on glucose concentration and was maximal below 10 mM-glucose. beta-2-Aminobicyclo[2.2.1.]heptane-2-carboxylic acid, an analogue of leucine, stimulated glutaminase flux, but inhibited the stimulation of glycogen synthesis by glutamine. Various purine analogues and inhibitors of purine synthesis were found to inhibit glycogen synthesis from glucose, but they did not abolish the stimulatory effect of glutamine on glycogen synthesis. The correlation between the rate of glycogen synthesis and synthase activity suggested that the stimulation of glycogen synthesis by glutamine depended solely on the activation of glycogen synthase. This activation of synthase was not due to a change in total synthase, nor was it caused by a faster inactivation of glycogen phosphorylase, as was the case after glucose. It could, however, result from a stimulation of synthase phosphatase, since, after the addition of 1 nM-glucagon or 10 nM-vasopressin, glutamine did not interfere with the inactivation of synthase, but did promote its subsequent re-activation. Glutamine was also found to inhibit ketone-body production and to stimulate lipogenesis.
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PMID:Stimulation of glycogen synthesis and lipogenesis by glutamine in isolated rat hepatocytes. 312 12

The hepatic metabolism of glutamine in rats adapted to a 15% casein high carbohydrate (HC) diet was compared to that in rats adapted to a 70% casein high protein (HP) diet. Portal glutamine concentrations in rats fed the HP diet were twice as high as those in rats fed the HC diet and glutamine was very efficiently extracted (40%) by the liver of rats fed the HP diet. From experiments of intraportal infusion of glutamine, it appeared that higher capacities of glutamine uptake develop in vivo in rats adapted to an HP diet. Hepatocytes isolated from such animals displayed higher capacities to metabolize glutamine to urea, even at physiological concentrations. This resulted from an increase of mitochondrial glutamine hydrolysis (observed in both intact and disrupted mitochondria) and from enhanced Na+-dependent glutamine transport (+50%, as measured by plasma membrane vesicles). In hepatocytes from rats fed the HC diet, glutamine breakdown was more efficiently stimulated by glucagon (and cAMP) than by vasopressin or epinephrine. In hepatocytes from rats fed the HP diet, this process was very responsive to both cAMP and Ca-dependent hormones. Metabolic adaptation to an HP diet results in the liver becoming a major site of glutamine utilization caused by adaptations of membrane transport, cell metabolism and tissue responsiveness to hormones.
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PMID:Control of hepatic utilization of glutamine by transport processes or cellular metabolism in rats fed a high protein diet. 336 36

The synthetic vasopressin analog 1-deamino-8-D-arginine vasopressin (dDAVP) has been shown to influence a wide range of cell-membrane-related events. Accordingly, the effect of dDAVP on membrane transport of various alkylating agents and amino acids was evaluated in L5178Y lymphoblasts in vitro. dDAVP stimulated melphalan uptake but conversely inhibited uptake of nitrogen mustard, choline (the natural transport substrate for the nitrogen mustard carrier), and leucine. No effect on the uptake of cyclophosphamide or glutamine was observed. Increased melphalan uptake was due to effects on both substrate influx and efflux. The effect of dDAVP on melphalan influx was particularly complex: dDAVP stimulated melphalan influx by amino acid transport system ASC but inhibited influx by system L, resulting in a net increase in unidirectional drug influx. Melphalan efflux was inhibited by dDAVP. Decreased uptake of nitrogen mustard, choline and leucine was due, at least in part, to decreased substrate influx. However, the mechanisms of inhibition were dissimilar: inhibition of substrate influx was non-competitive for choline but competitive for leucine. In conclusion, dDAVP induced diverse but apparently specific effects on membrane transport of several alkylating agents and amino acids. Since the accumulation of alkylating agents such as melphalan within tumor cells is a major determinant of cytotoxicity, dDAVP may have a role as a biological response modifier.
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PMID:Modulation of membrane transport of alkylating agents and amino acids by an analog of vasopressin in murine L5178Y lymphoblasts in vitro. 380 Oct 52

Using well-established solid-phase techniques, three new analogues of arginine-vasopressin (AVP) were synthesized. In these the glutamine residue in position 4 was replaced with an additional arginine. The new analogues were: [Arginine4]arginine-vasopressin ([Arg4]AVP), [2-thiopropionic acid1,arginine4]arginine-vasopressin (d[Arg4]AVP) and [1-thiocyclohexaneacetic acid1,arginine4]arginine-vasopressin (d(CH2)5[Arg4]AVP). [Arg4]AVP showed about the same antidiuretic activity as AVP but had only about 40% of its pressor activity. Unexpectedly, deamination caused a drop in the antidiuretic activity to about 50%. d(CH2)5[Arg4]AVP had practically negligible antidiuretic and low pressor effects.
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PMID:Synthesis, antidiuretic and pressor activities of [arginine4]arginine-vasopressin and two related analogues. 406 Sep 59

Cultured endothelial cells derived from cerebral microvessels separated from 2-day-old rat brain contain a specific beta 2 and alpha 2-adrenergic sensitive adenylate cyclase (AC). Among the various tested hormones, PGE1 and PGE2 were found to be the most potent activators, while adenosine, angiotensin I and II, gamma-aminobutyric acid and vasoactive intestinal peptide inhibited the enzyme activity. However, acetylcholine, histamine, serotonin, glycine, glutamine, bradykinin, neurotensin and vasopressin (Lysine and Arginine) had no effect on the adenylate cyclase activity in this model. The susceptibility of the cerebrovascular endothelial AC system to the vasoactive substances as well as presence of beta 2 and alpha 2-type adrenergic receptors in the cultured endothelium provides additional support for the proposed endothelial involvement in the regulation of cerebrovascular permeability and blood flow.
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PMID:Cerebral endothelial cell culture. I. The presence of beta 2 and alpha 2-adrenergic receptors linked to adenylate cyclase activity. 627 96

In isolated rat liver cells, vasopressin, like glucagon, promotes the metabolism of glutamine used at near-physiological concentration (1 mM). These findings indicate that, in vivo, both hormones might participate in the control of hepatic gluconeogenesis and ureogenesis from glutamine.
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PMID:Vasopressin promotes the metabolism of near-physiological concentration of glutamine in isolated rat liver cells. 671 87


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