scholarly journals The nature and properties of the inducible sodium-plus-potassium ion-dependent adenosine triphosphatase in the gills of eels (Anguilla anguilla) adapted to fresh water and sea water

1974 ◽  
Vol 144 (1) ◽  
pp. 69-75 ◽  
Author(s):  
John R. Sargent ◽  
Alison J. Thomson
Keyword(s):  
Fresh Water ◽  
Adenosine Triphosphatase ◽  
Sea Water ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
Anguilla Anguilla ◽  
Gill Tissue ◽  
Sodium Deoxycholate ◽  
Enzyme Preparations ◽  
Protein Components

1. Gill tissue from eels adapted to fresh water or to sea water was disrupted in 0.32m-sucrose containing 0.1% (w/v) sodium deoxycholate and the subcellular distribution of (Na++K+)-dependent adenosine triphosphatase was determined. 2. About 70% of the recovered enzyme was in a fraction sedimenting between 225000gav.-min and 6000000gav.-min; the specific activities of enzymes from tissues of freshwater and seawater eels were 16 and 51 μmol of phosphate/h per mg of protein respectively. 3. The enzymes from gills of freshwater and seawater eels were indistinguishable on the basis of a number of parameters. These included phosphorylation by [γ-32P]ATP, the binding of [3H]ouabain, the extent to which bound [3H]ouabain was displaced by increasing concentrations of KCl and pH optima. 4. Electrophoresis on polyacrylamide gels in sodium dodecyl sulphate showed that enzyme preparations from both sources had an identical number of protein components. 5. The higher specific activity of (Na++K+)-dependent adenosine triphosphatase from tissue of seawater eels was accompanied by increased amounts of two protein components. One of these proteins retained 32P after treatment of the enzyme with [γ-32P]ATP and had mol.wt. 97000; the other component was a glycoprotein with mol.wt. approx. 46000. 6. The results are discussed in terms of the nature of the transepithelial NaCl pumps in the gills of freshwater and seawater fish.

The effects of transecting the IXth and Xth cranial nerves on hydromineral balance in the eel Anguilla anguilla

1976 ◽  
Vol 64 (2) ◽  
pp. 461-475
Author(s):  
N. Mayer-Gostan ◽  
T. Hirano
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Cranial Nerves ◽  
Anguilla Anguilla ◽  
Vagus Nerves ◽  
Rapid Reduction ◽  
Ion Concentrations ◽  
Excess Loss ◽  
Na Efflux ◽  
Hydromineral Balance

The IXth and the Xth cranial nerves in Anguilla anguilla were transected, and the effects upon ion and water balance were studied in fresh water and sea water, and during transfer from fresh water and vice versa. In fresh water there is a slow demineralization due to an excess loss of Na and Cl ions. During freshwater to seawater transfer the eel survives only for 4–5 days. The fish do not drink and Na efflux does not increase enough to extrude excess ions. In sea water the glossopharyngeal and vagus nerves are necessary for the maintenance of the hydromineral balance. Denervation is followed by an increase in plasma ion concentrations. Na fluxes are not modified and increased water loss is not compensated by drinking. The rapid reduction of Na efflux during transfer from sea water to fresh water is not modified by denervation.

Kinetics of Water and Chloride Exchanges During Adaptation of the European Eel to Sea Water

1973 ◽  
Vol 58 (1) ◽  
pp. 105-121
Author(s):  
R. KIRSCH ◽  
N. MAYER-GOSTAN
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Anguilla Anguilla ◽  
Maximum Level ◽  
Progressive Increase ◽  
Plasma Sodium ◽  
European Eel ◽  
Drinking Rate ◽  
The One ◽  
Kinetics Of

Using isotopic procedures, the drinking rate and chloride exchanges were studied in the eel Anguilla anguilla during transfer from fresh water to sea water. 1. Following transfer to sea water there is a threefold increase of the drinking rate (lasting about 1 h). Then it falls to a minimum after 12-16 h and rises again to a maximum level about the seventh day after the transfer. Then a gradual reduction leads to a steady value which is not significantly different from the one observed in fresh water. 2. The changes with time of the plasma sodium and chloride concentrations are given. Their kinetics are not completely alike. 3. The chloride outflux increases 40-fold on transfer of the eel to sea water, but even so it is very low. After the sixth hour in sea water there is a progressive increase in the flux, so that on the fourth day it is higher (500 µ-equiv. h-1.100 g-1) than in the seawater-adapted animals (230 µ-equiv.h-1.100 g-1). 4. Drinking rate values in adapted animals are discussed in relation to the external medium. The kinetics of the drinking rate together with variations in body weights after freshwater-seawater transfer are discussed in relation to the possible stimulus of the drinking reflex. 5. Chloride fluxes (outflux, net flux, digestive entry) are compared and lead one to assume that in seawater-adapted fish one-third of the chloride influx enters via the gut and two-thirds via the gills.

RENAL FUNCTION IN THE EUROPEAN EEL (ANGUILLA ANGUILLA L.): CHANGES IN BLOOD PRESSURE AND RENAL FUNCTION OF THE FRESHWATER EEL TRANSFERRED TO SEA-WATER

1969 ◽  
Vol 43 (1) ◽  
pp. 9-19 ◽  
Author(s):  
I. CHESTER JONES ◽  
D. K. O. CHAN ◽  
J. C. RANKIN
Keyword(s):  
Blood Pressure ◽  
Renal Function ◽  
Fresh Water ◽  
Inorganic Phosphate ◽  
Sea Water ◽  
Anguilla Anguilla ◽  
Urine Flow ◽  
Inulin Clearance ◽  
European Eel ◽  
Clearance Rates

SUMMARY A method for the study of renal function and measurement of mean ventral and dorsal aortic blood pressure for the freshwater and seawater-adapted eel, and during transfer of the animal from fresh water to sea-water, is described. Freshwater eels have higher resting blood pressure, p-aminohippuric acid (PAH) and inulin clearance rates and urine flow than seawater eels. Urine from freshwater animals has low Na, K, Ca, Mg and Cl concentrations, while the clearance rate of inorganic phosphate exceeded that of inulin. Urine from seawater animals has high Na, Ca, Mg and Cl concentrations while that of inorganic phosphate was low. Clearance rates for Ca and Mg greatly exceeded those of inulin. During transfer from fresh water to sea-water there was an initial fluctuation in blood pressure, urine flow and PAH and inulin clearance rates which lasted about 2 hr. Thereafter these gradually declined to values observed for the seawater-adapted animal. The significance of PAH and inulin clearance rates in the study of renal function in the eel and in teleosts in general is discussed.

A light microscopic study of the action of sodium orthovanadate on the gills of fresh-water and sea-water eels (Anguilla anguilla L.)

1979 ◽  
Vol 59 (4) ◽  
pp. 859-865 ◽  
Author(s):  
K. F. Kelly ◽  
B. J. S. Pirie ◽  
M. V. Bell ◽  
J. R. Sargent
Keyword(s):  
Light Microscopy ◽  
Fresh Water ◽  
Constant Pressure ◽  
Sea Water ◽  
Anguilla Anguilla ◽  
Chloride Cells ◽  
Sodium Orthovanadate ◽  
Central Venous ◽  
Water Fish ◽  
Gill Filaments

Gills of fresh-water and sea-water eels were perfused at a constant pressure with physiological Ringer containing 10−6 M sodium orthovanadate and examined by light microscopy. The secondary gill filaments were markedly vasoconstricted in both freshwater and sea-water fish although the peripheral blood route around the secondary filaments was unaffected. The central venous space in the primary filament was largely unaffected. Significant constriction of both afferent and efferent arteries on the primary filament occurred. We conclude that orthovanadate vasoconstricts eel gills mainly at the level of the secondary filaments. The study also emphasizes that chloride cells are located on both the primary and secondary filaments of fresh-water gills but solely on the primary filaments of sea-water gills.

EFFECTS OF FRESHWATER ADAPTATION AND OF PROLACTIN ON SODIUM-POTASSIUMACTIVATED ADENOSINE TRIPHOSPHATASE ACTIVITY IN THE URINARY BLADDER OF TWO FLOUNDER SPECIES

1974 ◽  
Vol 62 (1) ◽  
pp. 11-14 ◽  
Author(s):  
S. UTIDA ◽  
MIE KAMIYA ◽  
D. W. JOHNSON ◽  
H. A. BERN
Keyword(s):  
Urinary Bladder ◽  
Atpase Activity ◽  
Fresh Water ◽  
Adenosine Triphosphatase ◽  
Sea Water ◽  
Sodium Potassium ◽  
Platichthys Stellatus ◽  
Freshwater Adaptation ◽  
Euryhaline Teleost ◽  
Kareius Bicoloratus

SUMMARY Sodium-potassium-activated adenosine triphosphatase (Na-K-ATPase) activity increased in the urinary bladder of the euryhaline teleost Platichthys stellatus after transfer from sea-water to fresh water. This increase also occurred after injection of prolactin into seawater Platichthys, simulating the results of freshwater transfer. In Kareius bicoloratus, which does not survive transfer to fresh water, prolactin does not increase bladder Na-K-ATPase activity. The differences in response of these two species to prolactin may be related to the degree of their euryhalinity. There may be a relationship between adaptability to fresh water and responsiveness of bladder Na-K-ATPase to prolactin.

scholarly journals A study of highly purified mucolipidosis III urinary N-acetyl-β-D-hexosaminidase B

1982 ◽  
Vol 204 (2) ◽  
pp. 557-563 ◽  
Author(s):  
S Hirani ◽  
L Little ◽  
A L Miller
Keyword(s):  
Ricinus Communis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Genetic Defect ◽  
Sodium Dodecyl ◽  
Acid Hydrolases ◽  
Enzyme Preparations ◽  
Normal Enzyme ◽  
Considerable Homology ◽  
Protein Components ◽  
Normal Urine

Highly purified N-acetyl-beta-D-hexosaminidase B from normal urine and urine of a patient with mucolipidosis III was used to determine whether it has undergone any of the alterations associated with this genetic defect. Examination by sodium dodecyl sulphate/polyacrylamide gel electrophoresis showed that both the enzyme preparations contained protein components with apparent Mr values of 55 000 and 28 000. No differences in the binding and apparent KI (50%) to concanavalin A of the normal and mucolipidosis III enzymes were detected. However, the patient's N-acetyl-beta-D-hexosaminidase B had a slightly greater affinity for the lectin from Ricinus communis than did the normal enzyme. Two-dimensional tryptic peptide maps of the corresponding normal and the patient's N-acetyl-beta-D-hexosaminidase B subunits showed considerable homology. These results indicate that N-acetyl-beta-D-hexosaminidase b does not undergo the significant carbohydrate alterations characteristic of other acid hydrolases in mucolipidosis III.

scholarly journals The partial purification of sodium-plus-potassium ion-dependent adenosine triphosphatase from the gills of Anguilla anguilla and its inhibition by orthovanadate

1979 ◽  
Vol 179 (2) ◽  
pp. 431-438 ◽  
Author(s):  
M V Bell ◽  
J R Sargent
Keyword(s):  
Microsomal Fraction ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
Anguilla Anguilla ◽  
Chloride Cells ◽  
Partial Purification ◽  
Sodium Orthovanadate ◽  
Turnover Number ◽  
Ouabain Binding ◽  
Beta Adrenergic Agonists

1. (Na+ +K+)-dependent ATPase was partially purified from eel gills by a procedure in which the microsomal fraction of crude preparations of chloride cells was selectively extracted with sodium dodecyl sulphate. 2. The microsomal specific activity was increased 2-fold during optimal treatment with detergent. 3. The final preparation (56% pure) had a specific activity of 341 mumol of ATP hydrolysed/h per mg of protein and a turnover number of 3560 min-1. The number of ouabain-binding sties equalled the number of sites phosphorylated by ATP. 4. Both sodium orthovanadate and ouabain inhibited the purified preparation more than the microsomal fraction, vanadate being more effective on an equimolar basis than ouabain. 5. Inhibition by orthovanadate was not enhanced at 28 mM-as compared with 1mM-MgCl2 and was not reversed by beta-adrenergic agonists (cf. Josephson & Cantley (1977) Biochemistry 16, 4572–4578). 6. Of various other metallic oxyanions tested only niobate proved an effective inhibitor of the enzyme although this anion was less effective than orthovanadate. 7. Orthovanadate partially inhibited phosphorylation of the enzyme by ATP in the presence of 28 mM-MgCl2.

Purification and Characterization of the Polygalacturonases of Tomato Fruits

1982 ◽  
Vol 9 (2) ◽  
pp. 155 ◽  
Author(s):  
ZM Ali ◽  
CJ Brady
Keyword(s):  
Specific Activity ◽  
Early Stage ◽  
Sodium Dodecyl ◽  
Divalent Metal Ions ◽  
Purification And Characterization ◽  
Tomato Fruits ◽  
Enzyme Preparations ◽  
The Third ◽  
C 50

Endopolygalacturonase [poly(1,4-α-D-galacturonide) glycanohydrolase, EC 3.2.1.15] was purified from ripening tomato fruits. The dominant enzyme in fruits at an early stage of ripening had a native molecular weight (Mr) of about 115 000, an isoelectric point (pI) of 8.6, and retained 50% of activity after 10 min at 70°C. Divalent metal ions enhanced the activity of this enzyme and ethylenediaminetetraacetate (EDTA) inhibited activity. In fully ripe fruits, two enzymes of Mr about 43 000 and 46 000 were most prominent. These enzymes each had a pI of 9.4; when a mixture of these two enzymes was heated for 10 min at 50°C, 50% of activity was lost. Antibodies raised against the smallest enzyme, Mr 43 000, reacted also with the larger enzymes. After denaturation in sodium dodecyl sulfate, the largest (Mr 115 000) and smallest (Mr 43 000) enzymes yielded polypeptides of identical size while the third enzyme (Mr 46 000) was slightly larger. All three enzymes were glycoproteins. From fully ripe fruits, enzyme preparations with specific activities of 1.7 �kat mg-1 were obtained. This specific activity exceeds those described previously for plant polygalacturonases.

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