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The present study is aiming at evaluating the hepatoprotective and antioxidant effects of Astragalus polysaccharide (APS) on the carbon tetrachloride (CCl(4))-induced hepatocyte and liver injury in common carp in vitro and in vivo. In vitro, APS (200, 400 and 800 μg/ml) was added to the carp primary hepatocytes before (pre-treatment), after (post-treatment) and both before and after (pre- and post-treatment) the incubation of the hepatocytes with CCl(4) at 8 mM in the culture medium. APS at concentrations of 200, 400 and 800 μg/ml significantly improved cell viability and inhibited the elevation of glutamate pyruvate transaminase (GPT), glutamate oxalate transaminase (GOT), lactate dehydrogenase (LDH) and malondialdehyde (MDA) and significantly increased the reduced level of superoxide dismutase (SOD). In vivo administration of APS at the doses of 1.5 and 3 g/kg in the diet for 60 days prior to CCl(4) intoxication significantly reduced the elevated activities of GPT, GOT and LDH and increased the reduced levels of total protein and albumin in the serum; meanwhile, the reduced levels of SOD, glutathione and total antioxidant capacity (T-AOC) were markedly increased and the MDA formation was significantly inhibited in liver tissue. Overall results proved the hepatoprotective action of APS, which is likely related to its antioxidant activity. The results support the use of APS as a hepatoprotective and antioxidant agent in fish.

Fifteen yearling steers were used to study the preventive effect of vitamin E on the protection against free radicals produced by carbon tetrachloride (CCl4). The animals were randomly divided in three equal groups and treated as follows: group A--previously injected (i.m.) with 15 IU/kg BW on the 15th and second day before the trial and drenched with 0.05 ml/kg BW CCl4; group B--only drenched with the same dose of CCl4; group C--drenched with a placebo. Food intake was recorded and blood samples collected daily for 8 days after the CCl4 drenching to compare the activity of aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT) and the levels of erythrocyte reduced glutathione (GSH) and serum malonyldialdehyde (MDA). Food intake was reduced in group B for the first 3 days (P < 0.05); higher activities of AST and gamma-GT were observed in the poisoned groups, nevertheless the overall values were lower in the group A than B (P < 0.02); only the group A reached the basal values of AST at the seventh day; higher levels of GSH and MDA were recorded in the poisoned cattle indicating the generation of free radicals. It was concluded that the preventive use of Vitamin E lessened the damage in hepatic tissue caused by the free radicals and prevented the anorexia caused by CCl4.

Poisoning resulting from exposure to a wide variety of industrial chemicals is not a common occurrence in horses, but it does happen on occasion. A wide range of toxicosis can occur from a wide range of industrial pollutants, such as dioxin, carbon tetrachloride, and tetrachloroethylene, to heavy metals, such as cadmium and zinc. The equine practitioner must consider industrial chemical toxicosis in differential diagnoses and work with a reputable veterinary diagnostic laboratory to confirm or rule out industrial chemical poisoning.

In the experiments performed with broilers, after a per os application of tetrachloromethane and cadmium (Cd+2), the activity of lactate dehydrogenase (LDH), leucylarylamidase (LA), and the GOT and GPT amino transferase was determined in the blood plasm. By means of an electrophoretic division of the blood plasm of clinically healthy broilers one enzymatically active fraction of LA and LDH was ascertained. The injury caused to the organism of poultry by carbon tetrachloride and cadmium did not affect the heterogeneity of these two enzymes. After an application of tetrachloromethane (CCl4) in the dose of 8 and 10 ml kg-1 the total activity of LDH and LA changed. The influence of cadmium on the organism in the total dose of 200 mg kg-1 resulted in the changed activity of LDH, GOT, and LA. From the results obtained it has been assumed that the examined activity of LDH, GOT, and LA can be utilized for the diagnosing of non-specific injuries of the organism of poultry.

Values of serum and plasma LDH in rats were comparatively studied, and the following results were obtained: 1) The activity of LDH increased in serum with time during clotting, but no changes of LDH activity were found in plasma. 2) When platelet rich plasma (PRP) was recalcified and allowed to clot, LDH-release from platelets with a corresponding increase of serum LDH was observed, but addition of ADP or thrombin to PRP did not have an effect on LDH-release. 3) LDH-release from platelets by calcium was not inhibited by aspirin, and it was influenced by the quality of the test tube. 4) Values of serum and plasma LDH on experimentally induced liver-damaged or kidney-damaged rats and tumor-bearing rats were examined in relation to their tissue damages, revealing that plasma LDH activity represents the condition of a disease better than serum LDH activity.

Plasma bile acid concentration was determined in normal dogs,sheep, calves and ponies for three days before and six days after liver damage, induced by carbon tetrachloride. In all species, a significant increase in plasma bile acid concentration was associated with a concomitant significant increase in plasma sorbitol dehydrogenase and transferase activity. Plasma bilirubin also significantly increased in all animals except the dogs. Results suggested that plasma bile acid levels could be used to test liver function in domestic animals.

In experimental bile obstruction in dogs, the most sensitive change in blood plasma composition is the increase in alkaline phosphatase activity which occurs after eight hours. Maximum alkaline phosphatase activities (approximately 100 times normal values) occur between the fifth and the 14th day. The increase in activity is accompanied by smaller increases in gamma-glutamyl transferase activity, and total bilirubin concentration also increases to a smaller extent and less regularly. Cholestasis also induces an intense cytolysis which is demonstrated mainly by increases in glutamate dehydrogenase and alanine amino transferase activities which are more intense and lasting than those induced by 0.5 ml/kg carbon tetrachloride.

Changes in serum enzyme levels, liver histology and liver function tests have been correlated to determine the usefulness of these tests in assessing liver status. The effects of carbon tetrachloride administration on these parameters has been determined in a group of 20 sheep. Normal levels, elevated levels after injury and the effect of elapsed time after injury are reported for serum glutamic dehydrogenase, sorbitol dehydrogenase, glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, lactate dehydrogenase, fructose-1-phosphate adlolase, alkaline phosphatase, cholesterol and proteins. Variation in the time of elevation of enzyme activities may be useful in determining the elapsed time between acute injury and serum sampling. In comparison to sheep fed an adequate diet, a diet with a restricted protein intake was associated with increased severity of histological lesions and decreased liver function.

Ataxia and depression developed in 21 of 50 (42%) laboratory cats wearing flea collars impregnated with 2,2-dichlorovinyl dimethyl phosphate (dichlorvos or DDVP) in a warm dry environment. Five (10%) of the cats died. Whole blood cholinesterase (ChE) activity was significantly (P smaller than 0.001) reduced in all cats and cervical dermatitis occurred in 37 (74%) of them.

The activities of serum alkaline phosphatase (serum ALP), leucine aminopeptidase (serum LAP), and alanine aminotransferase (serum ALT) were determined in 15 cats before and after treatment by 3 methods: common bile duct occlusion, left hepatic duct(s) occlusion, and carbon tetrachloride administration. Significant increases in serum ALP, LAP, and ALT activities occurred in all cats in the 3 groups. Sustained mean increases of ninefold in ALP and 13-fold in LAP occurred in the cats with common bile duct occlusion. Lesser mean increases of these enzymes (fourfold) occurred in the cats with partial biliary occlusion. Transient mean increases (100-fold) in ALT occurred in the carbon tetrachloride-treated cats. Urine ALP excretion was measured in 3 cats with common bile duct occlusion. There was no significant difference between rates of urine ALP excretion before and after common bile duct occlusion. Specific ALP activities of hepatic extracts from normal cats and biliary-obstructed cats were compared. Mean specific activity was onefold higher in liver from cats with common bile duct occlusion of 21 days' duration. The findings in the present studies were interpreted to indicate that serum ALP and LAP are useful to detect biliary occlusive disease in cats and, in conjunction with serum ALT, may be used to differentiate primary hepatodegenerative disease and biliary occlusive disease.

Graded hepatic damage was induced in mature lactating dairy cows to measure the sensitivity of several hepatic diagnostic tests. In a preliminary study, cows were dosed with .05, .10 and .20 ml/kg body weight of carbon tetrachloride. Extreme changes occurred in hepatic tests by 24 h post-dosing, and all died by 35 h with massive diffuse centrilobular necrosis of hepatic cord cells. Dosing was decreased to induce non-fatal hepatic changes. Cows in Groups 1, 2, 3 and 4 were orally dosed with .002, .004, .006 or .01 ml/kg body weight of carbon tetrachloride, respectively. Serum enzymes of hepatic origin, bilirubin, plus bromosulfophthalein dye clearance were assayed before dosing and up to d 14 post-dosing. Liver biopsies were performed 24 h post-dosing for histological evaluation and cytochrome P-450 content. Hepatic concentrations of cytochrome P-450 were decreased in all the dosed cows. Serum activities of sorbitol dehydrogenase and gamma-glutamyl transferase were elevated in cows of Groups 3 and 4 and glutamic-oxaloacetic transaminase in cows of Group 4 by 24 h. Serum alkaline phosphatase, glutamic-pyruvate transaminase, lactate dehydrogenase, bilirubin, urobilinogen and bromosulfophthalein dye clearance were not significantly different. Mild to moderate diffuse centrolobular necrosis was observed in livers of cow of Groups 3 and 4, but no pathological changes were seen in Groups 1 and 2.

Six calves were used to formulate a model of liver injury, following up the activity of the serum enzymes LAP, ALD, AP, GPT, GOT, OKT, and guanase. Studied were also the contents of blood sugar, calcium, phosphorus as well as some indices of the lipid metabolism. It was found that even with the least severe injuries of the liver there was a considerable rise of the OKT, guanase, GOT, GPT, and LAP activity. It is believed that the enzyme changes alone could serve as a specific index to detect the earliest injury of the liver.

Three calves were dosed orally with carbon tetrachloride at 0.05, 0.1 or 0.3 ml/kg body-weight. Plasma enzyme activities, clotting times, bilirubin concentrations and bromsulphthalein elimination times increased. These changes are associated with damage to the liver and are discussed in relation to the clinical syndrome. Three groups of seven calves were infected weekly with 10, 50 or 100 Fasciola hepatica metacercariae for 12 consecutive weeks. Maximum glutamate dehydrogenase and gamma glutamyltransferase activities in the plasma were greater with the larger infecting doses but there was no change in plasma clotting times.

Effects of induced cholestasis and hepatocellular necrosis and of fasting on serum biochemical constituents including bile acids, IgA, bilirubin, alkaline phosphatase, gamma-glutamyltransferase (GGT), arginase, and the clearance of sodium sulfobromophthalein were studied in 4 groups of equids. The reference value for serum bile acids, as determined by an enzymatic colorimetric procedure for horses and ponies was 5.94 +/- 2.72 mumol/L, there being no statistical difference for horses and ponies. Sample collection at time of feeding had no effect on serum bile acid concentration. Seemingly, serum bile acids, arginase, and GGT were the most sensitive indicators of cholestasis and/or hepatocellular necrosis and would form an essential minimum effective battery of tests to diagnose and prognose hepatic disease in equids. These tests provided a measure of hepatobiliary transport function (bile acids), cell necrosis (arginase), and cholestasis (GGT and bile acids).