Activity Of Enzymes In Blood Serum Research Articles

Synthesis of Pd nanoparticle and study the effect on Adenosine amino hydrolase (ADA) enzyme activity in blood serum

Chemical reduction with trisodium citrate as the reducing agent resulted in the successful formation of palladium nanoparticles (Pd NPs), and all of the material's components were synthesised in double-distilled water. UV-vis spectroscopy, X-ray diffraction, with Transmission Electron Microscopy were all utilised to investigate the Pd nanoparticles. According to TEM investigations, the average size of the Pd nanoparticles formed was 13.5 - 45 nm. Serum adenosine deaminase (ADA) activity in atherosclerosis patients was tested to see if Pd NPs had any effect. Serum ADA activity was considerably higher in individuals with atherosclerotic disease, both in those treated with Pd nanoparticles and in those who were not (P<0.01). Pd nanoparticles significantly lowered blood levels of ADA activity in atherosclerotic disease patients compared to those who did not receive Pd nanoparticles.

Properties and functions of TP/PD-ECGF — enzyme and angiogenic factor in norm and in neoplastic pathology

Thymidine phosphorylase is a protein which may has a dual action: it is a rate-limiting enzyme in thymidine metabolism and it is similar to the platelet – derived endothelial cell growth factor (PD/ECGF). The enzyme catalyzes the reversible reaction of phosphorolytic cleavage of thymidine to thymine and deoxyribose-1-phosphate. It has been found that TP has higher activity in tumor tissues. Also it is involved in a proliferative process in a wide variety of chronic inflammatory diseases. Increased expression of PD/ECGF in many tumors is associated with aggressive disease and/or poor prognosis. Its known that high TP activity is related to malignant angiogenesis and invasion.
 On the other hand, TP inhibits a hypoxia induced apoptotic pathway and enhances expression of various inflammatory cytokines and interferons. This apparent role of enzyme in tumor progression has prompted investigation a large number of TP inhibitors for applicability in chemotherapy backbone regimens. The enzymatic activity of PD/ECGF is being able to generate 5-fluorouracile from capecitabine and other precursors. Thus TP is identified as a prime target for developing novel anticancer therapies. The serum TP level in cancer patients provides useful prognostic information regarding both responses to chemotherapy and length of survival and should be used in planning appropriate therapy. TP could be suggested that control of individual enzyme activity in blood serum may be used as informative tool for monitoring of patients and treatment optimization.

Effect of Swiftlet’s (Collocalia Fuciphago) Nest Extract on the Malondialdehyde (MDA) and Superoxyde Dismutase (SOD) Activity on Hyperglycemic Rattus Norvegicius

Hyperglycemia that occurs in diabetic Mellitus leads to glycation reactions in protein molecules and oxidative stress resulting in damage to cells and organs. Swiftlet’s nest believed society could lower blood glucose. The objective of the study was to evaluate the effect of Swiftlet’s nest (Collocalia fuciphago) extract on glucose level, Malondialdehyde (MDA) levels, and Superoxide Dismutase (SOD) activity in blood serum. The study used Posttest-Only with Control Group Design, consisting of 1 control group (given aqua dest) and 3 treatment groups (dose 1; 10 and 100 mg/kg BW). Each group consisted of 6 Rattus norvegicius. Before being treated, Streptozotocin-induced rat at a dose of 68 mg/kg BW intraperitoneal. On the 7th day after induction, rats had elevated glucose ± 102 - 108 mg/dL. Then the rats were given water extract Swiftlet’s nest for 28 days orally. All data were analyzed by the Kruskal-Wallis test, followed by the Mann-Whitney test, with a 95% confidence level. The results of blood glucose levels in each group (K, P1, P2 and P3) were 111.0 vs 88.5 vs 86 vs 83 mg / dL (p = 0.035), MDA levels experienced an increase in the treatment group compared to controls namely 193.50 vs 193.83 vs. 198.50 nmol / mL, p = 0.001. While the SOD enzyme activity has increased, namely 0.0050 vs. 0.0075 vs. 0.0263%. In conclusion, Swiftlet’s nest water extract can reduce blood glucose levels and increase MDA levels and SOD enzyme activity in blood serum.

Eucalyptus viminalis leaf extract alters the productivity and blood parameters of healthy broiler chickens

Background and Aim:As an alternative to natural and chemically synthesized direct-acting bactericides, there has been an increase in the use of plant extracts, which possess a set of phytochemicals with potential for microbial disease control; this is due to the spectrum of secondary metabolites present in extracts, which include phenolic compounds, quinones, flavonoids, alkaloids, terpenoids, and polyacetylenes. The biologically active substances within plant extracts, which perform protective functions for plant tissues, can have ambiguous effects on the animal body. Therefore, the aim of this study was to assess the ability of gamma-octalactone, isolated from Eucalyptus viminalis extract, to inhibit various LuxI/LuxR quorum-sensing (QS) systems in bacteria, and to evaluate its effect on broiler chickens.Materials and Methods:Phytochemical analysis of E. viminalis extract was performed. The ability of gamma-octalactone to inhibit QS was evaluated using four different LuxI/LuxR bacterial test systems. In vivo assessments were performed on one hundred and twenty 7-day-old broiler chickens (Arbor Acres cross), split into four groups of 30 chickens: 1. Control group: Basic diet (BD); 2. experimental Group I: BD + gamma-octalactone at a dosage of 0.05 ml/kg live weight/day; 3. experimental Group II: BD + gamma-octalactone at a dosage of 0.1 ml/kg live weight/day; and 4. experimental Group III: BD + gamma-octalactone at a dosage of 0.2 ml/kg live weight/day. Hematological blood parameters were assessed using an automatic hematological analyzer (URIT-2900 Vet Plus, URIT Medial Electronic Co., China) and an automatic biochemical analyzer (CS-T240, Dirui Industrial Co., Ltd., China). Statistical analyses were performed using SPSS Statistics Version 20 (IBM); averages (M), standard deviations (σ), and standard deviation errors (m) were calculated. Results with p≤0.05 were considered significant.Results:Based on the phytochemical analysis results, libraries of compounds with putative QS inhibitory properties were compiled. Gamma-octalactone exhibited a pronounced inhibitory effect on the LuxI/LuxR QS systems, characterized by EC50 values of 0.15-0.4 mM. In the in vivo portion of this study, broiler chicken live weights increased in all experimental groups, with the most significant increase in Group III (14.0%), in relation to the control group. Blood serum from the experimental group chickens had significantly higher levels of triglycerides and uric acid (p≤0.05), in comparison to the control group chickens. With respect to blood serum enzyme activity and antioxidant status indicators, the experimental group chickens had a higher level of gamma-glutamyl transferase, an enzyme associated with amino acid metabolism, than those in the control group; this increase was especially pronounced in Group III, with 37.0% increase (p≤0.05). Superoxide dismutase and catalase levels were higher in the experimental groups than the control group, corresponding to increases of 30.4-56.2% (p≤0.05), 33.3-83.3%, and 27.9-45.5% (p≤0.05) in Groups I, II, and III (p≤0.05), respectively. Morphological blood parameters did not display significant changes due to gamma-octalactone.Conclusion:According to the results of this in vivo study in broiler chickens, gamma-octalactone, isolated from E. viminalis leaf extract and supplied at a dosage of 0.2 ml/kg live weight/day, led to an increase in the activity of blood plasma digestive enzymes, increased live weight, and had a positive effect on lipid metabolism and antioxidant status.

Effects of Purified Paper (Yellow) Wasp (Polistes flavus) Venom Toxins on Phosphatase Enzyme Activity in Blood Serum, Liver and Gastrocnemius Muscle Tissue of Albino Mice

Effects of Purified Paper (Yellow) Wasp (Polistes flavus) Venom Toxins on Phosphatase Enzyme Activity in Blood Serum, Liver and Gastrocnemius Muscle Tissue of Albino Mice

Impact of polycyclic aromatic hydrocarbon effluent on the enzyme activity in blood serum of freshwater food fish Cirrhinus mrigala

Impact of polycyclic aromatic hydrocarbon effluent on the enzyme activity in blood serum of freshwater food fish Cirrhinus mrigala

Impact of polycyclic aromatic hydrocarbon effluent on the enzyme activity in blood serum of freshwater food fish Cirrhinus mrigala

The purpose of this study was to estimate the acute toxicity of polycyclic aromatic hydrocarbon (PAH) effluent on Cirrhinus mrigala and to evaluate the lethal levels. The 120 hrs median lethal concentration of polycyclic aromatic hydrocarbon (PAH) effluent were found to be 20ppt for Cirrhinus mrigala. Further experiments were proceeded with sub lethal concentration of (1/10th conc. of LC50) polycyclic aromatic hydrocarbon (PAH) effluent which were evaluated from the LC50 value. After treatment the fishes were reared in ideal condition, then sacrificed dissected at different predetermined interval during the accumulation period, (i.e.) 1st day to 20th day, during the depuration period from 1st day to 15th day for Cirrhinus mrigala in polycyclic aromatic hydrocarbon (PAH) effluent treatment for assay studies. The enzyme activity studies carried out under sub lethal (1/10th conc. of LC50) in Blood Serum. The present study indicates that oil effluent induced alterations in the enzymatic activities of the freshwater food fish both at acute and sub-lethal concentrations. These alterations can be considered as a tool for biomonitoring of pharmaceutical drug substances in the aquatic environment. The present work also indicates that oil effluent causes considerable alterations in enzymes activities and is likely to induce tissue damage in Cirrhinus mrigala. Therefore, this effluent should be handling with care and prevent its entrance into aquatic environment.

Possible use of the growing liver biological set for hepatic recovery after toxic damage (an experimental study)

The lack of acceptable pharmacological approaches for restoration of the injured liver is associated with complex of mechanisms involved in hepatic regeneration and with difficulty of the target selection. The aim of this research was to study the hepatoprotective function of the extract from both the growing and regenerating liver containing a natural set of factors crucial for the hepatic restoration. Extracts from both regenerating liver of rats after 70% hepatic resection and the growing liver of neonatal pigs were obtained using own original technique. The set of resultant extracts was named as the hepatic regeneration set (HRS). HRS fractionation was carried out using the Toyopearl HW-50S sorbent. The efficiency of HRS and its fractions was estimated using a model of the mouse liver thioacetamide injury and monitoring hepatic enzyme activity in blood serum. The activities of AST and ALT in intact animals were 50 U/l and 80 U/l, respectively; after thioacetamide administration they increased to 2059±212 U/l and 4280±440 E/l, respectively (p<0.05). Treatment of injured animals with HRS from the rat regenerating liver resulted in a significant decrease of transaminase activities to 924±148 U/l (AST; p<0.05) and 1633±308 U/l (ALT; p<0.05). A similar effect was observed after treatment with HRS from the neonatal pig liver: the AST decreased to 937±138 U/l (p<0.05), while ALT activity decreased to 1710±237 U/l (p<0.05). HRs fractionation resulted in identification two active fractions characterized by much higher (8-29) hepatotropic effect that that of the whole extract. These fractions contained peptide/protein components with the range of molecular mass of 3-60 kDa (fraction 1) and 3-25 kDa (fraction 2a). Fraction 1 also contained some polynucleotides in fraction 1. Subsequent studies of these fractions exceeding the hepatotropic effect of original HRS is clearly needed to identify their individual components by immunochromatography methods, ELISA, MRM mass spectrometry and quantitative PCR.

Nanopore-based electrical and label-free sensing of enzyme activity in blood serum.

A generic strategy to expand the analytical scope of electrical nanopore sensing is presented. We specifically and electrically detect the activity of a diagnostically relevant hydrolytic enzyme and remove the analytically harmful interference from the biochemically complex sample matrix of blood serum. Our strategy is demonstrated at the example of the renin protease which is involved in regulation of blood pressure. The analysis scheme exploits a new approach to reduce sample complexity while generating a specific read-out signal. Within a single spin-column (i), the protease cleaves a resin-tethered peptide substrate (ii) which is affinity-purified using the same multifunctional resin to remove interfering blood serum components, followed by (iii) detecting the peptide via electrical nanopore recordings. Our approach is beneficial in several ways. First, by eliminating serum components, we overcome limitations of nanopore sensing when challenging samples lead to membrane instability and a poor signal-to-noise ratio. Second, the label-free sensing avoids drawbacks of currently used radiolabel-immunoassays for renin. Finally, the strategy of simultaneous generation and purification of a signal peptide within a multifunctional resin can very likely be expanded to other hydrolytic enzymes dissolved in any analyte matrix and exploited for analytical read-out methods other than nanopore sensing.

Sperm angiotensin-converting enzyme activity in Chernobyl victims and patients with chronic prostatitis.

The method for determination of angiotensin-converting enzyme activity in human spermatozoa and seminal plasma was developed. The number of total and active-motile spermatozoa was shown to be lower in Chernobyl victims than in healthy donors. The specific activity of angiotensin-converting enzyme in spermatozoa from Chernobyl victims was 12 times higher than that in donors. Similar results, although to a lesser extent, were observed in patients with chronic prostatitis. In contrast, the enzyme activity in blood serum and seminal plasma was identical for all subjects investigated.

Dynamics of products of glycolipid metabolism and activity of enzymes AST and ALT in different ecotypes of the Yakut horse breed

The dynamics of products of glycolipid metabolism and enzyme activity in blood serum of the Yakut horse breed depending on ecotypes and different natural and climatic conditions of Yakutia are investigated. Adaptation of Yakut horses to extreme climatic conditions is accompanied by a significant change in AST and ALT activity, content of alkaline phosphatase, cholesterol, triglycerides, urea, and glucose and has distinct seasonal expressivity.

Glutathione level and glutathione-dependent enzyme activities in blood serum of patients with gastrointestinal tract tumors

Objectives Glutathione (GSH) and enzymes cooperating with it – glutathione peroxidase (GSHPx), glutathione S-transferase (GST) and glutathione reductase (GSHR) – play crucial role in cell defence against reactive oxygen species (ROS), which are implicated in tumor disease. The aim of this study was to determine if neoplastic diseases of gastrointestinal tract may influence blood GSH level and its dependent enzyme activity. Design and methods Blood serum was obtained before and after surgery from patients with gastric, liver and colorectal cancers, and colorectal cancer liver metastases. Lipid peroxidation and GSH levels, and GSH-dependent enzyme activities were determined by means of spectrophotometric methods. Results Increased level of lipid peroxidation and significant differences in GSH level and GSHPx, GST and GSHR activities were observed in serum taken before and after surgery from patients with gastrointestinal tract tumors compared to those in control serum (from healthy blood donors). Conclusions Increase of lipid peroxidation and changes in GSH level and related enzyme activities, suggest oxidative stress in serum of patients with gastrointestinal tract tumor causes, which probably arise as a result of enormous production of ROS in the system. These alterations reflect the presence of functional defence mechanism against oxidative stress related firmly to the glutathione metabolism.

Effect of natural zeolite on biochemical and hematological parameters in blood, body mass and growth of calves

The work presents the results of investigations of the effect of natural zeolite (clinoptilolite type) on the degree of resumption of cloistral immunoglobulin, the value of hematological parameters and enzyme activity in blood serum (AST, ALT, and LDH), body mass, and daily growth of calves in the first three months of life. Investigations were carried out on three groups of 10 male and female calves each, with a 1:1 ratio of sexes, (control, K, and two experimental groups, I and II), of the black-and-white breed, Holstein type. All three groups of calves were fed with the usual rations (colostrum, collective cows' milk, fodder mix with 18% total proteins, and Lucerne hay).The experimental groups of calves, as opposed to the controls, received colostrums and collective cows' milk with the addition of a preparation based on natural zeolite in quantities of 5 and 10 g/l milk. The concentration of immunoglobulin G in blood serum of experimental groups of calves was significantly higher than the values of the control group (35.9?6.43 g/l in Group I; 32.5?7.39 g/l in Group II; 20.8?6.88 g/l in control group K). The results of the investigations of the values of hematological parameters (number of erythrocytes, hemoglobin concentration, and hematocrit value) do not show any digressions from the physiological values and are approximately the same in the experimental and the control groups of calves, which indicates that the examined quality of the zeolite-based preparation did not affect the degree of the resumption of iron and other oligoelements significant for erythropoietin. The data on the enzyme activity in blood serum indicate that the examined preparation does not cause any significant functional or morphological changes in the tissue of parenchymatous organs or muscles. There were no significant disorders in the health of calves of the experimental groups, while 3 calves of the control group had gastrointestinal disorders (diarrhea). Calves of experimental group I which received colostrum and collective cows' milk with an addition of 5g zeolite/l milk had a significantly greater average body mass and daily growth on the 90th day of life than calves of the control group (116.0-6.9: 105.3-6.4 kg, and 0.868:0.743 g). The addition of natural zeolite in quantities of 5 g/l colostrum or milk yields better results and has an advantage over the higher doze of zeolite of 10 g/l.

Influence of protein starvation on some lysosomal enzyme activities in blood serum of sheep

Abstract. Reactivity of none lysosomal enzymes in blood plasma of sheep has been estimated. After 48 h protein deprivation the activity of BGLU, BGAL, AAP and LAP increased significantly, NAGL and LL activity decreased, EL and KF activity remained unchanged.

A study of prolidase in mothers, their newborn babies and in non-pregnant controls.

The prolidase activity in serum and in erythrocytes was measured in 28 healthy mothers and in the cord blood of their newborn babies in using a modified Chinard method. 45 healthy non-pregnant women aged between 15-36 years formed a control group. Biochemical parameters (CK, BUN, C-peptid, AFP, Uric acid) were also measured. The serum and erythrocyte prolidase activities in maternal blood were 45.8+/-13.4 U/L and 37.8+/-2.7 U/g Hb respectively. There was no significant difference in the enzyme activities between pregnant women and the control group (p>0.05). However serum and erythrocyte prolidase activity in cord blood (20.3+/-8.2 U/L and 31.6+/-7.3 U/g Hb) was significantly different when compared with control group (53.4+/-14.7 U/L in serum and 42.3+/-10.3 U/g Hb in erythrocyte, p<0.001). There was a significant correlation between maternal and cord blood serum enzyme activity (r: 0.76 p<0.01). This correlation was also shown in erythrocyte prolidase activities of both groups (r: 0.49, p<0.05). Cord blood prolidase activity was positively correlated with birth weight (r: 0.89, p<0.01). Prolidase activity in cord blood was low even though collagen turnover is increased in fetal growth.

Effects of Trifluralin on Carp: Biochemical and Histological Evaluation

Acute and subacute toxicity of the herbicide trifluralin on fish was investigated in laboratory toxicity tests with carp. Median lethal concentrations were determined in acute tests. The 96-h LC50 value was 0.045 (0.036–0.051)mg/L. Fish were exposed to subacute concentrations of the herbicide (0.005, 0.01, and 0.02 mg/L trifluralin) in the 14-day toxicity tests and the effects on the relative growth rate, some biochemical parameters [alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanin aminotransferase (ALT) activities in serum, gills, liver, and kidney], gills, liver, and kidney structure were studied. A decrease in relative growth rate was found. An increase of functional enzyme activities in blood serum and the organs examined, particularly in the highest concentration of trifluralin indicated changes in the vital organs, was confirmed by histological analysis. The most severe changes (although mostly reversible) were found in the gills and kidney of the fish examined.

Effect of blood plasma and cerebrospinal fluid on functional properties of human hemoglobin

The method of determination of angiotensin-converting enzyme activity in human spermatozoa and sperm plasma was developed. The amount of total and active-mobile spermatozoa was shown to be less in Chernobyl victims than in healthy donors. Moreover, the specific activity of angiotensin-converting enzyme in Chernobyl victims spermatozoa calculated per 10(6) cells was 12-fold greater than in spermatozoa of the donors. Similar phenomenon, although to a les extent, was observed in patients with chronic prostatitis. The enzyme activity in blood serum and sperm plasma was also demonstrated to be similar for all groups investigated and equal to that in healthy donors.

Pathological events in experimental acute pancreatitis prevented by the bradykinin antagonist, Hoe 140

1. In a previous investigation, Hoe 140, a specific and potent bradykinin B2 receptor antagonist, prevented the pancreatic oedema and the hypotension observed during acute experimental pancreatitis; however, it augmented the associated rises in the serum activities of pancreatic enzymes. Therefore, we have now investigated the consequences of the pancreatic oedema for the fate of activated enzymes released into the tissue during the course of acute pancreatitis. 2. Acute oedematous pancreatitis was induced in rats, pretreated with captopril (50 mumol kg-1, i.p.), by hyperstimulation of the exocrine function of the pancreas with the cholecystokinin analogue, caerulein (4 nmol kg-1 h-1, i.v.), for up to 120 min. 3. Pancreatic oedema began to develop 10 min after the start of the caerulein infusion, reached a maximum within about 45 min, and then declined slightly. The development of the oedema parallelled the second phase of the caerulein-induced fall in blood pressure found in earlier experiments. No further extravasation of plasma proteins occurred during the 2nd hour of the caerulein infusion. The oedema formation was completely blocked in animals pretreated with the bradykinin receptor antagonist, Hoe 140 (100 nmol kg-1, s.c.). Pretreatment with aprotinin or soy bean trypsin inhibitor did not result in a significant inhibition of the oedema. 4. The haematocrit of animals with experimental pancreatitis showed a pronounced increase which started 10 min after the start of the caerulein infusion and reached maximal values at 60 min. The changes in haematocrit showed a reduction in total blood volume of 28% due to a 48% loss of plasma. This effect was completely blocked by Hoe 140. 5. In rats with caerulein-induced pancreatitis, there was a time-dependent increase in the activities of amylase and lipase in blood serum as well as in the pancreas. Pretreatment with Hoe 140 greatly augmented the caerulein-induced rise in enzyme activities in blood serum but potently attenuated it in the pancreas. The activities of trypsin in both the blood serum and the pancreas were below or near the limit of detection in all experimental groups.6. It is concluded that the second phase of hypotension in this model of acute pancreatitis is due to the liberation of kinins which cause a massive loss of blood plasma into the pancreas and into the retroperitoneal space. Activated enzymes are trapped in the pancreas, at least in part, by the oedema of the gland. Treatment with Hoe 140 prevents the oedema formation and greatly facilitates the egress of activated enzymes from the pancreas.

Angiotensin-converting enzyme activity in blood serum and lung tissue of spontaneously hypertensive rats

Angiotensin-converting enzyme (ACE) activity in blood serum and lung tissue was studied in spontaneously hypertensive rats. ACE activity in blood serum and lung tissue in normotensive and spontaneously hypertensive rats (SHR) was significantly different. In normotensive rats (NTR), ACE activity in serum was much higher than in SHR. In the lung tissue, the differences were less marked. During ontogenetic development, NTR demonstrated a decrease in ACE activity in serum and an increase in lung tissue, while SHR showed the total decrease in the enzyme activity.

Levels of enzyme activities in blood serum as indicators of a high copper status in sheep flocks.

SummaryThe relationship between the hepatic Cu‐level and certain biochemical constituents in the blood of lambs was studied. The activities of the enzymes glutamic oxaloacetic transaminase (E.C. 2.6.1.1.), sorbitol dehydrogenase (E.C. 1.1.1.14.) and to a lesser extent γ‐glutamyl transferase (E.C. 2.3.2.2.) can be considered as indicators of a high copper status of a flock. When the copper status is very high (&lt; 1500 μg Cu per g DM in the liver) the activity of lactate dehydrogenase (E.C. 1.1.1.27.) is strongly enhanced. For individual animals, the estimation of these enzymes is of little diagnostic value in predicting the Cu‐status. The influence of hepatic Cu‐levels lower than 600 μg per g DM on any of the parameters determined in the blood was slight.ZusammenfassungEnzymaktivitäten im Blutserum als Indikatoren für einen hohen Kupferstatus in SchafherdenDie Beziehungen zwischen dem Kupfergehalt der Leber und gewissen biochemischen Parametern im Blut der Lämmer wurde untersucht. Die Aktivitäten folgender Enzyme können als Indikatoren für einen hohen Kupferstatus einer Herde betrachtet werden: Glutamat‐Oxalacetat‐Transaminase (E.C. 2.6.1.1.), Sorbit‐Dehydrogenase (E.C. 1.1.1.14.) und in einem geringeren Ausmaß γ‐Glutamyl‐Transferase (E.C. 2.3.2.2.). Bei sehr hohem Kupferstatus (&lt; 1500 μg Cu pro g Trockenmasse in der Leber) ist auch die Aktivität der Laktat‐Dehydrogenase (E.C. 1.1.1.27.) stark erhöht. Bei individuellen Tieren dagegen ist die Bestimmung der Enzymaktivitäten von geringer diagnostischer Aussagekraft bezüglich des Kupferstatus. Bei Kupfergehalten in der Leber von weniger als 600 μg pro g TM war der Einfluß auf die untersuchten Parameter nur gering.RésuméActivités enzymatiques dans le sérum sanguin comme indicateurs d'un statut élevé du cuivre dans des troupeaux de moutonsOn a examiné le rapport entre le taux du cuivre dans le foie et certains paramètres biochimiques dans le sang d'agneaux. Les activités enzymatiques suivantes peuvent être considérées comme indicateurs pour un statut élevé en cuivre d'un troupeau: glutamate‐oxalacétate‐transaminase (E.C. 2.6.1.1.). sorbit‐déhydrogénase (E.C. 1.1.1.14.) et dans une moindre mesure γ‐glutamyl‐transférase (E.C. 2.3.2.2.). L'activité de lactate‐déhydro‐génase (E.C. 1.1.1.27.) est fortement augmentée avec un statut très élevé du cuivre (&gt; 1500 μg Cu pro g substance sèche dans le foie). La détermination des activités enzymatiques est d'une moindre valeur pour le diagnostic concernant le statut du cuivre chez des animaux pris individuellement. L'influence sur les paramètres recherchés fut faible avec des taux de cuivre dans le foie inférieurs à 600 μg pro g substance sèche.ResumenLos niveles de actividades enzimáticas en el suero sanguíneo coma indicadores del estado elevado de cobre en rebaños de ovinosSe examinaron las relaciones entre el contenido de cobre en el hígado y ciertos parámetras bioquímicos en la sangre de los corderas. Las actividades de las enzimas siguientes se pueden considerar como indicadoras de un estado elevado de cobre: glutamato‐oxalacetato‐transaminasa (E.C. 2.6.1.1.), sorbita‐dehidrogenasa (E.C. 1.1.1.14.) y, en menor magnitud, γ‐glutamil‐transferasa (E.C. 2.3.2.2.). Con estado muy elevado de cobre (&gt; 1500 μg Cu por g MD en el hígado) también se encuentra muy incrementada la actividad de la lactato‐dehidrogenasa (E.C. 1.1.1.27.). Sin embargo, en animales individuals la valoración de las actividades enzimáticas tiene un valor diagnóstico de predicción muy escaso en cuanto al estado de cobre. En los niveles de cobre en hígados inferiores a 600 μg por g MD era solo muy limitado el influjo sobre los parámetras determinados en sangre.