Of sheep kidney

The present paper will outline some of our recent EPR and NMR studies using Mn2+ as a paramagnetic probe of sheep kidney (Na+ + K+)-ATPase and Gd2+ as a paramagnetic probe of sarcoplasmic reticulum Ca2+-ATPase. Estimates of the relevant electron spin relaxation times and some features of the interaction between substrates and activators with the enzyme-metal complexes will be inferred from the EPR spectra and the accompanying nuclear relaxation data. 

An ac field could also stimulate ATP hydrolysis activity of sheep kidney Na, K-ATPase and Ecto nucleotide diphosphohydrolase, at 37 °C (31). ATP hydrolysis does not require energy input. The increase in the ATP splitting activity reflects the sensitivity of chemical rate constants to an electric field as in eqs 7 and 8. Figure 3 shows the ATP hydrolysis activity of Ecto ATPase at 37 °C as a function of frequency when a 5.0-V/ cm (peak-to-peak) ac field was used. As mentioned, Blank and Soo used 1-mV/ cm ac fields to stimulate the ATP splitting activity of Na, K-ATPase (19, 20). Their results are also presented here. 

Phosphonoacetic acid, a nonlabile, putative analogue of carboxyphosphate, is a potent inhibitor of sheep kidney pyruvate carboxylase. It is also a fair inhibitor of phosphoenol pyruvate carboxylase. In reply, it should be noted that phosphonoacetic acid and its derivatives are biologically active in many systems the rationale for this activity is often elusive, but probably dependent on the ability of these compounds to act as analogues of a number of diphosphate-containing biomolecules. 

Fig. 10.6.2. In vivo deformation of three types of calibrated microspheres. The length and width of three types of microspheres has been measured on histological slides after embolization of sheep kidneys. The microsphere deformation was calculated by the formula deformation (%) = 100 X (length-width)/width. The graph summarizes the results expressed in boxplots. A view of the deformation of each microsphere type is given below the graph...

The D-amino acid oxidase of sheep kidney has been purified it is a flavoprotein containing FAD. It is of low spedfidty and catalyses the oxidative deamination of all the amino acids of the D-series with the exception of glutamic acid. It does not act on amino acids of the L-series, or on glydne. 

Type of amino acid n-Amino acid oxidase of sheep kidney L-Amino acid oxidase of cobra venom L-Amine acid oxidase of N. crAmino acid oxidase of N. cra a L-Amino acid oxidase of Mytiba eduH ... 

Fig. 6.16 The model of Na+,K+-ATPase from sheep kidney according to E. Amler, A. Abbott and W. J. Ball. The shading indicates various functional areas of the dimeric enzyme ... 

Data are scarce in mammals that link zinc concentrations in tissues with environmental zinc perturbations. In harbor porpoises, impaired homeostasis reportedly occurs when zinc exceeds 100 mg/kg FW liver however, livers of many species of marine mammals routinely exceed this value (Wood and Van Vleet 1996). Elevated zinc concentrations, in mg Zn/kg DW tissue, were >120 in cattle liver, >180 in sheep kidney, and >250 in sheep liver (Table 9.9), but their significance is unclear. No international regulations or guidelines applicable to zinc are available (USPHS 1989). No U.S. Food and Drug Administration action level or other maximum acceptable concentration exists for zinc, and therefore no Final Residue Value can be calculated (USEPA 1987). This seems to be a high priority research need. 

D-Amino acid oxidase (EC 1.4.3.3) extracted from sheep kidney possesses low selectivity and at pH 8-9 will oxidise many D amino acids, whereas L-amino acid oxidase (EC 1.4.3.2) from snake venom (Crotalus adaman-teus) at pH 8-9 catalyses the oxidation of many L amino acids. However, as these enzymes show different reactivity towards different amino acids, the results for a sample that contains several D and L amino acids may be difficult to interpret. The use of these enzymes is therefore only recommended for the measurement of one isomer of an isolated amino acid. They may also be used to remove an unwanted isomer from a sample containing both to allow subsequent measurement of the other. 

Ford JH, Evans J. 1985. Distribution of 5 -nucleotidase in the tissues of sheep and the effect of kidney and liver lesions on the activity of enzyme in plasma and urine. Res Vet Sci 39 103-109. 

In tissues of sheep treated orally with a single dose of 5 mg/kg bw, residue levels of closantel were 0.06-0.09 ppm in fat and muscle and up to 0.47 ppm in kidney and liver at 56 day withdrawal at 84 days, residues could not be detected in fat and muscle, whereas liver and kidney contained levels as low as... 

Because of its relatively short excretion time, xylazine produces residue concentrations below 0.1 ppm in all edible tissues of sheep and cows except the injection site, liver, and kidney, at 20 h after intramuscular administration (115). In addition, xylazine is not excreted with cow milk. Hence, only 2 days are recommended in Norway between treatment and slaughter of cattle or the delivery of milk for human consumption. However, liver and kidney should be discarded if slaughter has taken place less than 4 days after medication. 

The mechanism of action of spleen exonuclease is similar to that seen for venom exonuclease (19-21) but different from the processive type of attack exhibited by E. coli RNase II, sheep kidney exonuclease, and polynucleotide phosphorylase (22, 23), in which cases each polynucleotide molecule is completely degraded before the enzymes attack a new molecule. The results of Bernardi and Cantoni (12) contradict the previous beliefs that the enzyme has an intrinsic, though weak, endonucleolytic activity (5) and that a phosphate group in a terminal 5 position makes a polynucleotide chain completely resistant to the enzyme (15, 24, 25). 

Kidney samples from cattle (125), sheep (128) and pigs (940) were analysed for the presence of this group of veterinary drugs. No residues were detected in cattle or sheep kidney. Of the 940 samples of pig kidneys tested 20 samples (2.1%) were found to have detectable residues with residues in four (0.4%) samples exceeding (1,700 /xg/kg, 230 /xg/kg, 230 /xg/kg, and 180 /xg/kg the MRL of 100/xg/kg). 

Figure 1A. Scatchard plot of the binding of Mn2 to (Na + K )-ATPase from sheep kidney medulla (21). In this figure ( ) is the native enzyme, (O) is the...

Three membrane-bound adenosine triphosphatase enzymes have been characterized using Mn(II) and Gd(III) electron paramagnetic resonance (EPR) and a variety of NMR techniques. Mn(II) EPR studies of both native and partially delipidated (Na+ + K+)-ATPase from sheep kidney indicate that the enzyme binds Mn2+ at a single, catalytic site with Kq = 0.21 x 10- M. The X-band EPR spectrum of the binary Mn(II)-ATPase complex exhibits a powder line shape consisting of a broad transition with partial resolution of the 55 n nuclear hyperfine structure, as well as a broad component to the low field side of the spectrum. ATP, ADP, AMP-PNP and Pj all broaden the spectrum, whereas AMP induces a substantial narrowing of the hyperfine lines of the spectrum. 

Vernon, R.G., Faulkner, A., Finley, E., Pollock, H., Taylor, E. 1987. Enzymes of glucose and fatty acid metabolism of liver, kidney, skeletal muscle, adipose tissue and mammary gland of lactating and non-lactating sheep. J. Anim. Sci. 64, 1395-1411. 

Conversation It said its magical properties were the benefits it gives to other plants that grow near it. It is of help to sheep—their liver and kidneys, and aids the eyes of sheep. Generally good for horses but the animals only eat it if they need it. For humans it is good for blood (the roots and flowers), the leaves for bruises. It is a happy little plant and reaches out for others to be in happiness. 

The extraction procedures used for thyrocalcitonin preparation have been applied to many other tissues, in a search for further hypocalcemic agents. Hirsch et al. (H4) were unable to demonstrate hypocalcemic activity in extracts of ox thymus, rat pituitary, or rat parathyroid. Rat liver, kidney, and salivary gland likewise yielded inactive extracts on assay in the rat. Gudmundsson et al. (G4) found no significant activity in pig liver, bovine parathyroid, or kidney. Extracts of dog lung, kidney, myocardium, skeletal muscle, spleen, brain, liver, and pancreas, when prepared by methods that yield potent extracts from the thyroid, failed to demonstrate hypocalcemic activity (CIO). Extracts of sheep liver and of gluteal muscle showed no activity in the sheep, and high-calcium perfusion of the thymus, isolated from parathyroid tissue, produced no... 

In domestic and experimental animals, renal effects have been observed following both acute and chronic oral exposures to selenium compounds. Administration of a single oral (subroute not specified) dose of sodium selenite at 5 mg selenium/kg/day produced hydropic degeneration of the kidney in sheep (Smyth et al. 1990). In a study of the toxicity of L-selenomethionine to long-tailed macaques by nasogastric intubation, two animals administered 0.24 mg selenium/kg/day aspirated vomitus secondary to emesis, developed obvious gastritis, and died of anorexia, one after 10 days and the other after 15 days of... 

The interactions of Mn2+ with the membrane-bound (Na++K+)-ATPase from sheep kidney medulla have been examined by kinetic and magnetic resonance techniques (80,81). EPR and water proton relaxation rate studies show that the enzyme binds Mn2+ at one tight binding site (Kd=0.88 /tM). Kinetic studies yield an activator constant for Mn2+ of 0.88 /M, identifying the one tight Mn2+ binding site as the active site of the ATPase. 

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