The Metabolism of Gammekane and Related Compounds

<p>1. A detailed kinetic study has been made of the glutathione S-aryl-transferases from the New Zealand grass grub (Costelytra zealandica) and from sheep liver. The insect enzyme behaves in accordance with a Michaelis-Menten model for two-substrate enzymes. It is inhibited by the sulphonphthaleins, phthaleins, fluoresceins and dicarboxylic acids competing with glutathione, while the sheep-liver enzyme is not susceptible to this type of inhibition. From this, and other data obtained from a study of the variation of kinetics with pH, it is proposed that two basic groups (possibly lysine residues) are involved in binding of glutathione to the insect enzyme, while only one such group appears in the sheep-liver enzyme. Binding of the aromatic substrate to the enzyme in both species may involve a histidine residue. 2. The accumulation of little significant radioactivity in diluant 2gamma-pentachlorocyclohexene (gamma-PCCH) during the in vitro metabolism of [14C]gamma-hexachlorohexane (gamma-HCH) suggests that the PCCH's are not formed as free intermediates during the metabolism of the HCH's. However, certain ambiguities introduced with the experimental techniques used preclude the complete exclusion of this possibility. 3. gamma-HCH, gamma-PCCH and delta-PCCH metabolized in vivo by M.domestica and C.zealandica and in vitro by preparations from both species, all produce as the principal metabolite a glutathione conjugate with chromatographic properties identical with those of authentic S-(2,4-dichlorophenyl)glutathione. There is, however some doubt as to the identity of the S-substituent moiety. 4. The in vitro metabolism of gamma-HCH and delta-PCCH is glutathione-dependent and is inhibited by various phthaleins and sulphonphthaleins. The in vivo metabolism of delta-PCCH in C.zealandica is profoundly affected by this type of compound, but its effects on the rate of metabolism in vivo of delata-HCH in M.domestica and C.zealandica are only marginal. 5. The enzyme concerned in the metabolism of delta-PCCH has been shown to differ from aryltransferase in M.domestica and C.zealandica by gel filtration techniques and by differences in activity in different enzyme preparations. The delta-PCCH-metabolising activity appears to be associated with a DDT dehydrochlorinase activity. In M.domestica, there appears to be, in addition, a second DDT dehydrochlorinase with only a low cross-specificity towards delta-PCCH.</p>

The Metabolism of Gammekane and Related Compounds

<p>1. A detailed kinetic study has been made of the glutathione S-aryl-transferases from the New Zealand grass grub (Costelytra zealandica) and from sheep liver. The insect enzyme behaves in accordance with a Michaelis-Menten model for two-substrate enzymes. It is inhibited by the sulphonphthaleins, phthaleins, fluoresceins and dicarboxylic acids competing with glutathione, while the sheep-liver enzyme is not susceptible to this type of inhibition. From this, and other data obtained from a study of the variation of kinetics with pH, it is proposed that two basic groups (possibly lysine residues) are involved in binding of glutathione to the insect enzyme, while only one such group appears in the sheep-liver enzyme. Binding of the aromatic substrate to the enzyme in both species may involve a histidine residue. 2. The accumulation of little significant radioactivity in diluant 2gamma-pentachlorocyclohexene (gamma-PCCH) during the in vitro metabolism of [14C]gamma-hexachlorohexane (gamma-HCH) suggests that the PCCH's are not formed as free intermediates during the metabolism of the HCH's. However, certain ambiguities introduced with the experimental techniques used preclude the complete exclusion of this possibility. 3. gamma-HCH, gamma-PCCH and delta-PCCH metabolized in vivo by M.domestica and C.zealandica and in vitro by preparations from both species, all produce as the principal metabolite a glutathione conjugate with chromatographic properties identical with those of authentic S-(2,4-dichlorophenyl)glutathione. There is, however some doubt as to the identity of the S-substituent moiety. 4. The in vitro metabolism of gamma-HCH and delta-PCCH is glutathione-dependent and is inhibited by various phthaleins and sulphonphthaleins. The in vivo metabolism of delta-PCCH in C.zealandica is profoundly affected by this type of compound, but its effects on the rate of metabolism in vivo of delata-HCH in M.domestica and C.zealandica are only marginal. 5. The enzyme concerned in the metabolism of delta-PCCH has been shown to differ from aryltransferase in M.domestica and C.zealandica by gel filtration techniques and by differences in activity in different enzyme preparations. The delta-PCCH-metabolising activity appears to be associated with a DDT dehydrochlorinase activity. In M.domestica, there appears to be, in addition, a second DDT dehydrochlorinase with only a low cross-specificity towards delta-PCCH.</p>

A Field Evaluation of the LuciTrap and the Western Australian Trap with Three Different Baits Types for Monitoring Lucilia cuprina and Lucilia sericata in New Zealand

Flytraps can be used on farms to monitor the populations of primary strike flies (Lucilia cuprina and Lucilia sericata) and, hence, offer a view regarding the incidence of flystrike on sheep. This study aimed to contrast the specificity and effectiveness of the LuciTrap with its combination of three chemical lures (Lucilures) and the Western Australian Trap with three bait types (LuciLure, Sheep liver with 30% sodium sulphide and squid). A mean model and rate model were fitted to the data. The mean model showed no difference (p > 0.05) in the mean weekly catch for L. cuprina between the Western Australian Trap with LuciLures and the Western Australian Trap baited with sheep liver with 30% sodium sulphide (p < 0.05). Whereas, for L. sericata, no difference (p > 0.05) was found between the Western Australian Trap with LuciLures, the Western Australian Trap baited with sheep liver with 30% sodium sulphide and the LuciTrap. The rate model illustrated that the Western Australian Trap with sheep liver with 30% sodium sulphide and LuciTrap did not differ (p > 0.05) for L. cuprina and L. sericata. Combined, these results indicate that New Zealand farmers can use either the LuciTrap or the Western Australian Trap with sheep liver with 30% sodium sulphide to monitor these target species.

Disorders of Major Inflammatory Factors and Histopathological Lesions in Excess-iron-fed Sheep Liver

Background: Iron plays a key role in biological metabolism as an essential microelement. Excess iron may cause pathological damage to the body. The purpose of this work is to explore the disorders of major inflammatory factors and histopathological lesions in the liver of excess-iron-fed sheep. Twenty German Mutton Merino sheep were randomly divided into 4 groups, control group (CON), iron-excess group one (IronE1), iron-excess group two (IronE2) and iron-excess group three (IronE3), respectively. Each group was fed with basal diets supplemented with 50 (CON), 500 (IronE1), 1000 (IronE2), and 1500 (IronE3) mg/kg as ferrous sulfate monohydrate (FeSO4 ·H2O). After 75 days, the liver was removed and collected. A variety of methods were utilized to detect indicators of sheep liver. Results: The histopathological damage of liver in sheep was rather severe with the excess of iron. Hemosiderin deposits were also obviously discovered. The results also showed that the expression of both protein and mRNA of IL-1β, TNF-α and IFN-γ reduced, but the factors of IL-2, IL-6, NF-κB and TGF-β1 obviously increased in the liver of each iron excess group. Corresponding changes were also discovered with the addition of iron dosage. The content of inflammatory factors above showed a significant change with an addition of 1500 mg/kg iron into the basic diet, which indicated that excess iron inhibited the release of IL-1β, TNF-α and IFN-γ in the sheep liver. The inflammation caused by excess iron extenuated by reducing the content of these three pro-inflammatory factors. The expression of IL-2, IL-6, NF-κB and TGF-β1 increased. As pro-inflammatory factors induced inflammation, anti-inflammatory factors also increased to protect the body from tissue damage. Conclusions: It can be concluded that excess iron can change the expression of main inflammatory factors in sheep liver, which will be an instructive significance to the development of medical prospect for sheep breeding and disease diagnosis.

Some heavy metals residues in beef and sheep Liver in Anbar province

The aim of the study To see the effect of location, season and display time on the accumulation of some heavy metals (Lead, copper, zinc, cadmium and cobalt) in sheep and cattle liver. Liver samples were obtained from three districts in Anbar province (Ramadi, Hit and Baghdadi). This study began from January 2017 to November 2017 for all seasons (winter, spring, summer and autumn) Samples were taken from the liver immediately after slaughter for cattle and sheep at 8 am and taken at 4 pm for all areas of study. The results of the study were summarized in the quadratic overlap of the animal type, season, location and time as follows: The highest concentration of lead in liver (38.86 μg / g liver) was recorded in sheep for spring and evening in Ramadi. The lowest concentration was in sheep in Baghdadi for morning and winter (20.06 micro g / g liver). The highest concentration of copper in the liver (34.65 microgram / g liver) was recorded in cows in Ramadi for the winter season and evening time. The lowest concentration was in the sheep liver during the summer season for morning time in the city of al-Baghdadi (20.43 microgram / g liver). The highest concentration was in the liver (603.99 microgram / g liver) in the sheep for the autumn season and the evening time in the city of Ramadi. The lowest concentration was in the sheep in the city of Baghdadi for morning and summer (560.32 microgram / g liver). The highest concentration of cadmium in the liver (30.88 micro g / g liver) was in sheep in Ramadi for the autumn and evening season, and the lowest concentration was in beef in the summer season for morning time in al-Baghdadi city (9.66 μg / g liver). Cobalt was the highest concentration (1.34, 1.34 and 1.35 micro g / g liver) in cow and sheep liver, autumn, summer and evening time for Ramadi. While the lowest concentration of sheep and cattle liver for the city of Baghdadi for the winter season and morning time (0.64 and 0.63 microgram / g liver).

Purification and Characterization of Xanthine Oxidase from Liver of the Sheep (Ovis Aries)

Xanthine oxidase is a commercially important enzyme with wide area of medical applications to develop diagnostic kits. Xanthine oxidase was extracted, purified and characterized from sheep liver (SLXO). The purification procedure involved acetone precipitation and chromatography on DEAE-cellulose and Sephacryl S-300 columns. The sheep liver xanthine oxidase was homogeneously purified 31.8 folds with 3.5 U/mg specific activity and 24.1% recovery. SLXO native molecular weight was 150 kDa and on SDS-PAGE appeared as single major band of 75 kDa representing a homodimer protein. Isoelectric focusing of the purified SLXO resolved into two closely related isoforms with pI values of 5.6 and 5.8. The apparent Km for xanthine oxidase at optimum pH 7.6 was found to be 0.9 mM xanthine. FeCl2 and NiCl2 increased the activity of SLXO, while CuCl2 and ZnCl2 were found to be potent inhibitors of the purified enzyme. Allopurinol inhibits SLXO competitively with one binding site on the purified molecule and Ki value of 0.06 mM.