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)

Tamm-Horsfall protein (THP), a normal constituent of mammalian urine, has been determined in rat urine under various conditions in an attempt to elucidate the physiological role of this glycoprotein. Experiments were designed to assess whether THP production is related to the process of urine concentration or to the transport activity of the thick ascending limb of the loop of Henle (TAL), the nephron segment where it is produced. For this purpose, THP excretion was measured, by radioimmunoassay, in adult male rats under 4 different conditions induced by the following chronic treatments: (1) furosemide (12 mg/day in osmotic minipumps); (2) increased water intake; (3) antidiuretic hormone (ADH) infusion (50 ng DDAVP/day in osmotic minipumps) in rats of the Brattleboro strain with hereditary hypothalamic diabetes insipidus; (4) high-protein (32% casein) versus low-protein diet (10% casein). Each experiment included 6 experimental and 6 control rats. After treatment for 1-3 weeks, 24-h urines were collected for determination of urine flow rate, osmolality, and creatinine and THP concentrations. No significant changes in THP excretion were observed in experiments (1) and (2) despite 5- to 7-fold-differences in urine flow rate. Antidiuretic hormone treatment in (3) slightly lowered THP excretion (287 +/- 53 vs. 367 +/- 41 micrograms/day per 100 g body weight; p less than 0.005), whereas high-protein diet, in experiment (4), led to a 50% increase in THP excretion (446 +/- 57 vs. 304 +/- 79 micrograms/day per 100 g body weight; p less than 0.001). Expressing THP excretion relative to that of creatine did not change these findings. These results show (1) that chronically established changes in the level of diuresis, chronic furosemide-induced blockade of the Na,K,Cl-cotransporter or the absence of ADH in Brattleboro rats have little or no impact on the level of THP production, and (2) that THP production is independent of the intensity of transport in the TAL, since two conditions which both are known to increase the transport rate of solutes in the TAL (ADH infusion and high-protein diet), resulted in opposite changes in THP excretion. It is concluded that the rate of THP synthesis is neither linked to the process of urine concentration nor to the ion transport activity of the TAL.
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PMID:Tamm-Horsfall protein excretion during chronic alterations in urinary concentration and protein intake in the rat. 172 Feb 54

The present study was designed to test the possible role of vasopressin in the renal response to dietary protein. This possibility was suggested by the similarity of effects on renal function and morphology of chronic high-protein intake and chronic stimulation of urine concentration. Adult male Brattleboro rats, genetically unable to produce vasopressin, were fed high-protein (32% casein = HP, n = 8) or low-protein (10% casein = LP, n = 9) diet for 7 wk. Renal function was evaluated by clearance techniques based on 24-h urine collections in metabolic cages. The response to a single injection of the vasopressin analogue 1-desamino-8-D-arginine vasopressin (DDAVP) was also tested. Kidney weight and height of the different renal zones were assessed at the end of the study. HP diet increased urea excretion nearly sevenfold. Water intake increased by 57% (P less than 0.001) and urine flow rate by 71% (P less than 0.01). Urine osmolality rose from 104 to 181 mosmol/kgH2O (P less than 0.001). At variance with what occurs in rats with endogenous vasopressin (Sprague-Dawley; Bouby, N., et al. Kidney Int 34: 4-12, 1988), HP diet increased creatinine clearance per unit body weight by only 14% and did not change free water clearance, renal mass, and height of inner stripe of outer medulla. However, the rise in urine osmolality and drop in free water clearance after DDAVP were significantly greater in HP- than in LP-fed Brattleboro rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vasopressin is involved in renal effects of high-protein diet: study in homozygous Brattleboro rats. 199 84

Tryptase was purified 13,000-fold to apparent homogeneity from rat skin. The two-step procedure involved ammonium sulfate fractionation of the initial extract followed by combined sequential affinity chromatography on agarose-glycyl-glycyl-p-aminobenzamidine and concanavalin A-agarose. The purified enzyme had a specific activity toward N-benzoylarginine ethyl ester (BzArgOEt) of 170 mumol/min mg-1 and was obtained in a yield of 28% as determined by the specific substrate, H-D-Ile-Pro-Arg-p-nitroanilide. Rat skin tryptase was thermal labile, losing 50% of its activity when preincubated for 30 min at 30 degrees C. The presence of NaCl (1 M) improved thermal stability and was necessary for long-term storage. Heparin did not stabilize the enzyme against thermal denaturation, and heparin-agarose failed to bind the enzyme. Rat skin tryptase was inhibited by diisopropylphosphofluoridate, antipain, leupeptin, and aprotinin but not by alpha 1-antitrypsin, ovomucoid, or soybean or lima bean trypsin inhibitors. Substrate specificity studies using a series of tri- and tetrapeptidyl-p-nitroanilide and peptidyl-7-amino-4-methylcoumarin substrates demonstrated the existence of an extended substrate binding site. Rat skin tryptase hydrolyzed [Arg8]vasopressin, neurotensin, and the oxidized B-chain of insulin at the -Arg8-Gly9-NH2, -Arg8-Arg9-, and -Arg22-Gly23-bonds, respectively. No general proteinase activity was observed toward casein, hemoglobin, or azocoll. Rat skin tryptase had a Mr of 145,000 by gel filtration. The subunit Mr was either 34,000 or 30,000 depending on the electrophoretic technique used. Treatment of the enzyme with peptide N-glycosidase F (N-glycanase) decreased the subunit Mr by 4000. The enzyme exhibited multiple isoelectric forms (pI's of 4.5-4.9). Rat skin tryptase was found to be related statistically to other tryptases on the basis of amino acid composition. The N-terminal amino acid sequence was Ile1-Val2-Gly3-Gly4-Gln5-Glu6-Ala7-+ ++Ser8-Gly9-Asn10-Lys11-Trp12-Pro13- Trp14- Gln15-Val16-Ser17-Leu18-Arg19-Val20- --21-Asp-22Thr23-Tyr24-Typ25-, with a putative glycosylation site at residue 21. This sequence was 72-80% homologous with the N-terminus of other tryptases but only 40% homologous with that of bovine trypsin.
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PMID:Tryptase from rat skin: purification and properties. 203 67

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 separate and combined effects of prenatal protein deficiency (6% casein) and prenatal nitrofen (2,4-dichlorophenyl-p-nitrophenyl ether) exposure (12.5 mg/kg on gestational d 7-21) on renal morphology in the 21-d fetal and postnatal rat were examined. Body weights and kidney weights were reduced in prenatally protein-deprived (PPD) pups at birth and on postnatal day (PND) 10. Numbers of mature glomeruli, creatinine clearance, water diuresis, and response of antidiuretic hormone (ADH), but not the concentrating ability, were lower in the PPD neonates. These changes suggest that prenatal protein deficiency delays renal development and possibly results in a decrease in glomerular clearance and in tubular response to a water load and to antidiuretic hormone. Prenatal nitrofen exposure reduced body weight and kidney size on PND 0 and 10. An increased incidence of hydronephrosis was indicated in the nitrofen-exposed fetus. Prenatal nitrofen exposure depressed the ability to excrete excess water, the response to ADH, and urine-concentrating ability. The functional deficits indicate tubular dysfunction, but little or no effect on glomerular function, as indicated by the absence of an effect on creatinine clearance. Postnatal survival was reduced to 22% by PND in the PPD plus nitrofen pups. Also, prenatal nitrofen exposure increased the susceptibility of the glomeruli in the gestational day (GD) 21 PPD fetus to the adverse effects of prenatal protein deficiency. By PND 10 the toxic effects were of the same order. Renal dysfunction may contribute to the increased mortality in PPD plus nitrofen pups by reducing the ability to respond to stress, but the effects are not sufficiently marked to be considered the primary cause of death.
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PMID:Kidney morphology and function in the young of rats malnourished and exposed to nitrofen during pregnancy. 374 36

Microorganisms in ruminal ingesta and pure cultures of anaerobic ruminal bacteria of different physiological and morphological groups incorporated (14)C from labeled 2-methylbutyrate during growth. The radioactivity was incorporated mainly into lipid and protein. Isoleucine was the only labeled amino acid found in acid hydrolysates of protein from either pure or mixed cultures. Radioactivity in isoleucine synthesized from 2-methylbutyrate-1-(14)C was entirely in carbon-2. Thus, the carboxylation of 2-methylbutyrate is a pathway for synthesis of isoleucine different from that operative in many aerobic and facultative microorganisms. The specific activity of isoleucine from 2-methylbutyrate by Bacteroides rumminicola 23 increased with higher concentrations of 2-methylbutyrate (2.6 to 44 x 10(-5)m) in the growth medium. At the highest concentration, the specific activity of isoleucine synthesized was 40% of the specific activity of the 2-methylbutyrate in the growth medium. The use of enzymatic casein hydrolysate, oxytocin, or vasopressin rather than ammonia as nitrogen source for growth of strain 23 depressed the incorporation of 2-methylbutyrate into isoleucine. Synthesis of isoleucine from 2-methylbutyrate appears to be an important reaction in the rumen.
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PMID:Isoleucine biosynthesis from 2-methylbutyric acid by anaerobic bacteria from the rumen. 581 42

A post-proline cleaving enzyme [prolyl endopeptidase, EC 3.4.21.26] was purified about 3,700-fold from an extract of bovine brain by a series of column chromatographies on DEAE-Sephadex, hydroxyapatite and PCMB-T-Sepharose, and gel filtration on Sephadex G-200 using N-carbobenzoxy-Gly-Pro-beta-naphthylamide (Z-Gly-Pro-2-NNap), thyrotropin releasing hormone (TRH) and oxytocin as substrates. The purified enzyme appeared homogeneous as judged by disc gel and SDS gel electrophoreses. The enzyme was most active at pH 7.5 and 7.2 with Z-Gly-Pro-2-NNap and TRH, respectively, and hydrolyzed peptide bonds involving Pro-X (X=amino acid, peptide, ester and amide) bonds of synthetic substrates, oxytocin, vasopressin, neurotensin, substance P, tuftsin, bradykinin, and insulin B chain. However, the enzyme was inert toward collagen, gelatin, and casein. The enzyme was completely inactivated by diisopropylphosphorofluoridate (DFP), Z-Gly-Pro-chloromethyl ketone and p-chloromercuribenzoate (PCMB), while it was not inhibited by phenylmethane sulfonylfluoride (PMSF) or metal chelators. Determination of the amino acid composition revealed that the enzyme contained 25 half-cystines. Modification of three cysteine residues of the enzyme by PCMB led to complete inactivation. The isoelectric point of the enzyme was 4.8, and the molecular weight was estimated to be 76,000 by ultracentrifugal analysis and 75,000-74,000 by both gel filtration and sodium dodecyl sulfate (SDS) gel electrophoresis, suggesting that the enzyme is present as a monomer. These results indicate that the post-proline cleaving enzyme from bovine brain is very similar to those previously purified from lamb brain and kidney in its enzymatic properties, substrate specificity and physicochemical properties, in sharp contrast with the results obtained by Tate, who reported that the bovine brain prolyl endopeptidase was inert toward oxytocin, vasopressin and bradykinin.
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PMID:Post-proline cleaving enzyme (prolyl endopeptidase) from bovine brain. 636 Oct 10

1. Water-loaded rats anaesthetized with ethanol were used for the detection of antidiuretic hormone (ADH). 2. Litter-mates were divided into groups and placed on different diets during the fourth week of life directly after weaning, and maintained on their respective diets for approximately 1 month and their sensitivity to vasopressin was determined. 3. The rats maintained on a diet of only vegetable or vegetable plus casein supplement showed a greater sensitivity to exogenous vasopressin than rats maintained on a standard laboratory diet (pellets). 4. It is proposed that the quantitative relationship between ADH and urine flow is dependent upon the previous history of water consumption.
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PMID:Increased sensitivity of ADH bio-assay in rats by change in diet. 738 76

Human blood platelets contain high levels of non-receptor protein tyrosine kinases of the Src family, particularly pp60c-src, suggesting an important role for these enzymes in platelet physiology. Indeed, in response to various agonists of platelet function, a number of proteins become phosphorylated at tyrosine residues. However, no enzymic activation of an Src-related tyrosine kinase has yet been shown in platelets. In searching for the kinase(s) responsible, we found that all agonists tested that directly or indirectly activate protein kinase C in platelets (phorbol 12-myristate, 13-acetate, thrombin, vasopressin, collagen, calcium ionophore A23187) increased the overall activity of pp60c-src determined by IgG phosphorylation in an immunocomplex assay in the presence of low ATP concentrations. On the other hand, elevation of cyclic AMP directly by forskolin or indirectly by prostaglandin E1, or elevation of cyclic GMP by sodium nitroprusside did not significantly affect the activity of the enzyme. To substantiate the differences in enzyme activity, we determined Km and Vmax, values of pp60c-src from resting and thrombin-stimulated platelets. Thrombin treatment increased substrate affinity of pp60c-src as indicated by a 2- to 3-fold decrease in the Km values for ATP and the exogenous protein substrate casein. Vmax. values were only slightly altered under the assay conditions used. To further rule out modifications of pp60c-src in phosphorylation as a probable cause of the changed substrate affinity, we analysed tryptic phosphopeptides of immunoprecipitated, 32P-labelled pp60c-src of unstimulated and stimulated platelets. The platelet agonists listed above induced an increase in pp60c-src phosphorylation at Ser-12, which is the amino acid phosphorylated by protein kinase C. Surprisingly, we found that elevation of cyclic AMP did not affect 32P labelling of pp60c-src. On the basis of our data, we suggest that phosphorylation at Ser-12 might be one of the signal-triggering events that cause the increase in substrate affinity of pp60c-src.
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PMID:Substrate affinity of the protein tyrosine kinase pp60c-src is increased on thrombin stimulation of human platelets. 769 43

Pittman, K. A. (Agricultural Research Service, Beltsville, Md.), and M. P. Bryant. Peptides and other nitrogen sources for growth of Bacteroides ruminicola. J. Bacteriol. 88:401-410. 1964.-Representative strains of Bacteroides ruminicola were found to utilize peptide nitrogen or ammonia nitrogen, but not to utilize significant amounts of free amino acid nitrogen or the nitrogen from a variety of other low molecular weight compounds for growth. All strains grew well in a defined medium containing glucose, minerals, B-vitamins, heme, volatile fatty acids, methionine, and cysteine, with ammonia as the main nitrogen source. Methionine and cysteine were required by some strains. The only compounds found to replace ammonia as the main nitrogen source were a few proteins; tryptic digests of protein; peptide-rich fractions of Sephadex G-25 fractionated tryptic digests of casein; and the octapeptides, oxytocin and vasopressin. Most of the nitrogen present in these compounds was utilized. However, the organism did not utilize nitrogen from any of 12 dipeptides, triglycylglycine, glutathione, or mixtures of free amino acids. Possible reasons for the inability of B. ruminicola to utilize low molecular weight nitrogen compounds are discussed.
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PMID:PEPTIDES AND OTHER NITROGEN SOURCES FOR GROWTH OF BACTEROIDES RUMINICOLA. 1420 57


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