Comparative study of copper and zinc metabolism in cattle and camel

At an experimental farm, five camels and five cows were fed a similar basal diet for 6 mo. They received oral trace element supplementation for 3 mo (day 22–112). This supplementation included zinc, copper, selenium, managanese, iodine, and cobalt, and corresponded to twice the requirements generally recommended for cows. Plasma copper and zinc concentrations were significantly lower in the camels (61 μg/100 mL for copper and 38 μg/100 mL for zinc) than in the cows (111 and 83, respectively). The supplementation had no effect on plasma zinc concentration in the camels in spite of the low observed values in this species. Liver copper concentration at the beginning of the trial was lower in the camels (9 ppm) than in the cows (35 ppm), and stayed at lower levels during the entire supplementation period. There was no clear difference in fecal excretion of copper and zinc between the camels and the cows. The results suggested that trace element requirements are lower in camels than in cows and that camels regulate their plasma zinc concentration at a very low level (<40 μg/100 mL).     

Copper,zinc, and selenium in human blood and urine after injection of sodium 2,3-dimercaptopropane-1-sulfonate: a study on subjects with dental amalgam

This study investigated the effects of a single dose of intravenously administered sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) on the essential elements copper, zinc, and selenium in human blood and urine. The possible role of dental amalgam was also addressed. Eighty individuals, divided in four groups according to the presence or absence of dental amalgam fillings and symptoms self-related to such fillings, were given DMPS (2 mg/kg body wt) and 500 mL Ringer’s acetate intravenously. Urine and blood were collected prior to the injection, and thereafter at intervals over a 24-h period. Cu, Zn, and Se concentrations were determined by atomic absorption spectrometry methods. A statistically significant increase in the concentrations of Cu and Zn in urine was observed 30 and 120 min after the DMPS injection compared to the preinjection concentrations. The concentrations of Se were not affected. The cumulated excretion over 24 h after DMPS injection constitutes only from 0.1% to 0.7% of the body content of these elements. There was no effect of different amalgam statuses on Cu and Zn excretion. We found a temporary decrease (4–7%) in the concentrations of Cu, Zn, and Se in blood 15 and 30 min after DMPS, but this seems to be the result of dilution factors. Administration of a single dose of DMPS does not affect the body stores of the essential elements Cu, Zn, and Se.     

Stimulation of urinary copper excretion by trientine(R) in nickel-sensitive patients

Trientine^(R) is not an effective drug for the treatment of intractable hand dermatitis in nickel-sensitive patients. In a controlled, double-blind study this chelator, on oral administration, failed to stimulate nickel excretion. Early morning urine samples from two groups of nine patients were analyzed by atomic absorption spectrophotometry in a stabilized Temperature Platform Furnace equipped with Zeeman background correction. Group 1 patients received placebo for 6 wk, then a 4-wk rest before crossover. Group 2 received the drug in the first period. No difference in Ni levels between the placebo period and the drug period in either group was demonstrated, nor was there any significant improvement in the hand eczema. Copper was measured in the same urine samples using the same instrumentation, but with atomization off the wall. There was a considerable increase in copper excretion during the drug treatment period. Group 1 excreted a mean 538±378 (SD) μg/L, which represented a mean increase of 787±653 % (SD). Group 2 excreted a mean 960±410 (SD) μg/L; a mean difference of 630±398 % (SD). It was concluded that the use of Trientine^(R) in subjects of normal copper status should be carefully controlled and monitored.     

High arsenic intake raises kidney copper and lowers plasma copper concentrations in rats

The effect of high arsenic intake on copper metabolism was investigated. Male rats aged 6 wk had free access to purified diets containing either 0 or 100 mg As/kg diet and demineralized water for a period of 2 wk. Arsenic was added to the diet in the form of NaAsO₂. The high-arsenic diet decreased feed and water intake and body weight gain, but significantly increased liver weight. Kidney weight was not affected. Arsenic feeding drastically elevated kidney copper concentration, but significantly reduced copper concentration in plasma. Both true absorption and biliary excretion of copper were decreased significantly in rats fed the high-arsenic diet. True copper absorption was lowered essentially through the lower copper intake in the rats fed arsenic. It is speculated that arsenic feeding primarily leads to copper accumulation in the kidney, followed by a decrease in feed intake and thus in true, absolute copper absorption, a decrease in plasma copper concentration, and a decrease in biliary copper excretion.     

Copper absorption,endogenous excretion,and distribution in Sprague-Dawley and lean (Fa/Fa) Zucker rats

We previously observed a rapid reduction in plasma ceruloplasmin activity in lean Zucker (Fa/Fa) rats fed a marginal copper (Cu)-deficient diet compared to similarly fed obese Zucker (fa/fa) and lean Sprague-Dawley rats. In an effort to understand the mechanisms underlying this response, we utilized the isotope dilution method to investigate the absorption and excretion of Cu in lean Zucker rats fed control and marginal Cu diets. Sprague-Dawley (SD) and homozygous lean Zucker rats were fed either a Cu-adequate (Cont; 7.5 μg Cu/g diet) or a low Cu (Low; 1.1 μg Cu/g diet) casein-based diet for 23 d. Two weeks following initiation of the dietary treatment, each rat was injected intramuscularly (im) with 11.2 μCi of⁶⁷Cu. Urine and feces were collected daily. On the 9th d following isotope injection, rats were killed and tissues collected. Significant dietary effects were observed in the relative absorption and endogenous fecal excretion of⁶⁷Cu. The tissue distributions of nonisotopic Cu and⁶⁷Cu activity were also different between dietary treatments. Tissues from rats fed the low-Cu diet typically had high concentrations of⁶⁷Cu and low concentrations of nonisotopic Cu compared to controls. An increase in relative⁶⁷Cu absorption was evident for rats fed the low-Cu diet (57.2 and 39.3%, for SD Low, Zucker Low, respectively, and 17.9, and 28.5% SD Cont and Zucker Cont, respectively). Rats fed the low-Cu diet also had reductions in endogenous fecal excretion of⁶⁷Cu compared to their respective controls. Although strain effects were not evident for either percent Cu absorption or endogenous fecal Cu excretion, the relative adaptive changes appeared more marked for the Sprague-Dawley rats compared to the lean Zucker rats.     

Influence of inositolhexaphosphori acid (phytic acid) on the copper distribution in tissues and the excretion of copper in rats

The aim of the present study was to investigate the effect of the administration of phytic acid on copper (Cu) concentrations in several different rat tissues. The animals used were divided into three groups: Group A (received a diet supplemented with 2% phytic acid), group B (received a diet supplemented with 10% phytic acid) and group C (control). At the end of the experiment, the animals were sacrificed and the concentration of copper was determined in the different tissues.

Phytic acid significantly increased Cu concentration in the duodenum of the animals of both groups as well as in the lungs and blood of the animals of group A. The copper concentration was also increased in the uterus and bone of the animals of group B.

On the other hand, the stomach copper concentration of the animals of both groups, the heart and lung copper concentrations of the animals of group B as well as the jejunum, colon and hair copper concentrations of the animals of group A were significantly decreased. Copper excretion through feces was significantly decreased in the animals of both groups, while the excretion through urine was not significantly affected by the administration of phytic acid.

In conclusion, the administration of phytic acid can produce translocation and/ or elimination of copper in various tissues of rats.     

重组人甲状旁腺素（1-34）在大鼠体内的组织分布和排泄

目的：研究重组人甲状旁腺素（1-34）[rhPTH（1—34）]在大鼠体内的组织分布和排泄情况,为进一步的临床实验提供参考。方法：用^125I-同位素示踪法结合TCA酸沉淀法测定各主要器官组织的总放射性浓度和酸沉淀部分放射性浓度,获得rhPTH（1-34）的尿粪排泄和胆汁排泄数据。结果：各主要器官组织的总放射性浓度排序由高到低依次为：尿、肾、膀胱、肠内容物、肌肉、血清、肾上腺、空肠、肝、肺脏、卵巢、肠淋巴结、脾、胸腺、心脏、脂肪、睾丸和脑;大鼠皮下注射。^125I-rhPTH（1-34）后,骨骼组织中放射性分布低于血浆,但消除缓慢,血浆浓度4h较15min降低了78％,而骨骼浓度多数仅降低了50％以下;注射后72h,尿、粪分别排出注入放射性量的73．6％±10．9％和3．2％±1．3％,尿、粪合计排出注入放射性量的76．8％±11,4％;注射后12h,胆汁中累积排出注入放射性的6．64％±1．04％。经分子筛排阻HPLC证实,^125I-rhPTH（1-34）不与大鼠的血浆蛋白发生结合。结论：rhPTH（1-34）在泌尿系统中的分布较高,在脂肪和脑中最低,提示药物不易透过血脑屏障;就全身放射性分布而言,在骨骼中分布较高,提示药物具有一定的靶向性;rhPTH（1-34）主要经尿的形式排泄。     

Increased urinary excretion of zinc and copper by mercuric chloride injection in rats

The effects of HgCl₂ on urinary excretion of Zn, Cu and metallothionein at different time intervals were observed in male Wistar rats. The rats were given a daily intraperitoneal injection of²⁰³HgCl₂ (0.5 or 1.0 mg Hg kg^–1) for 2 days.²⁰³Hg, Zn, Cu and metallothionein in urine, kidney and liver were analyzed. Significant increases in urinary Zn and Cu concentrations were found in HgCl₂-dosed groups. Elevated urinary Zn and Cu concentrations were accompanied by an increased metallothionein excretion in urine at different time periods. Zn concentration in urine remained elevated during the entire observation period of 7 days. There were also increased concentrations of Cu and Zn in the renal cortex in one of the two exposed groups. The results indicate that urinary Cu and Zn are related to the manifestation of renal toxicity and/or the synthesis of metallothionein in kidney induced by mercury.     

The effect of various dietary zinc concentrations on the biological interactions of zinc,copper, and iron in rats

Three groups (14 rats each) were fed one of the following diets for 8 wks: a control purified basal diet containing 12 ppm zinc, 5 ppm copper, and 35 ppm iron; the basal diet with less than 2 ppm zinc; or the basal diet supplemented with 1000 ppm zinc. Rats fed the zinc-deficient diet had decreased weight gain, moderate polydipsia, and intermittent mild diarrhea. The zinc-supplemented rats had a cyclical pattern of food intake and weight loss from weeks 5 to 8. Tissue concentrations suggest that zinc and copper were not mutually antagonistic with chronic dietary imbalances. If tissue element concentrations reflected intestinal uptake, then competition and/or inhibition of intestinal uptake occurred between zinc and iron. The fluctuations in tissue element concentrations that occurred with increased duration of the study were at variance with previous studies of shorter time periods. The dietary proportions of zinc, copper, and iron appear to influence zinc, copper, and iron metabolism at the intestinal and cellular transport levels over a given period of time.     

Change in apparent and true absorption and retention of dietary zinc with age in rats

Two groups of 16 rats each were fed the same diet with 12.9 ppm Zn. Nine days after each animal was injected with⁶⁵Zn for assessing fecal zinc of endogenous origin, zinc intake and excretion were determined for a six-day period at the age of about five (group I) and nine (II) weeks. At mean growth rates of 5.1 and 5.2 g/day, food consumption per gram of gain was 2.01 g in group I vs 2.86 g in II. Overall, zinc retention amounted to 21 vs 25 μg Zn/g of gain. Apparent absorption averaged 92 vs 74% of Zn intake (132 vs 189 μg/day), while true absorption averaged 98 vs 92%. It was concluded that endogenous fecal zinc excretion was limited to the indispensable loss (F _em) in group I (7 μg/day), while it exceeded this minimum loss in group II (33 μg/day). True retention, which reflected total zinc utilization (true absorption times metabolic efficiency), was derived from apparent absorption plusF _em (11 μg/day for group II according to the greater metabolic body size of the rats). It averaged 98% of Zn intake in group I vs 80% in group II. The mean metabolic efficiency was 100% vs 87%. The conclusion was that these marked differences between age groups in utilizing the dietary zinc reflected the efficient homeostatic adjustments in absorption and endogenous excretion of zinc to the respective zinc supply status.     

Regional distribution of metallothionein, zinc, and copper in the brain of different strains of rats

The regional brain distribution of metallothionein (MT), zinc, and copper in the brain was determined in nine anatomical regions (olfactory bulb, cortex, corpus striatum, hippocampus, thalamus plus hypothalamus, pons plus medulla oblongata, cerebellum, midbrain, and white matter) and was compared between two different strains of rat (Sprague-Dawley [SD] and Lewis). No significant difference was observed in the whole-brain MT level between the two strains (17.8 ± 3.4 μg/g in SD rats and 20.3 ± 2.3 μg/g in Lewis rats). In SD rats, however, MT was more highly expressed in the white matter than in the other regions studied. In contrast, MT concentration was highest in the cortex and lowest in the olfactory bulb in Lewis rats. The MT levels in the cortex, corpus striatum, hippocampus, and thalamus plus hypothalamus were significantly lower in SD rats than in Lewis rats. In both strains, the olfactory bulb contained markedly higher levels of both zinc and copper than the other regions (27.9 ±6.8 μg/g zinc in SD rats and 27.6 ± 6.9 μg/g zinc in Lewis rats, and 5.2 ± 1.5 μg/g copper in SD rats and 11.1 ± 4.8 μg/g copper in Lewis rats). The next high-est zinc levels were seen in the hippocampus, whereas the next highest copper levels were in the corpus striatum in both SD and Lewis rats. The high levels of zinc and copper in the olfactory bulb were not accompanied by concomitant high MT concentrations. These results indicate that the strain of rat as well as the anatomical brain region should be taken into account in MT and metal distribution studies. However, the highest concentrations of zinc and copper in olfactory bulb were common to both SD and Lewis rats. The discrepancy between MT and the metal levels in olfactory bulb suggests a role for other proteins in addition to MT in the homeostatic control of zinc and copper.     

Effect of long-term swimming exercise on zinc,magnesium, and copper distribution in aged rats

Trace element content of different tissues might be altered by both age and exercise training. We aimed to determine the effects of a 1-yr swimming protocol (60 min/d, 5 day/wk) on tissue levels and the distribution of zinc (Zn), magnesium (Mg), and copper (Cu) in aging rats. Three groups were formed: sedentary and trained old groups and a young control group. Tissue Zn, Mg, and Cu concentrations were measured in the kidney, heart, liver, lungs, and gastrocnemius and soleus muscles. Kidney zinc concentration significantly decreased in the sedentary old group compared to the young control group (p<0.01) and was significantly higher in the trained old group compared to the sedentary old group (p<0.01), whereas Zn levels in the soleus muscle significantly increased in the sedentary old group in comparison to young controls (p<0.05). Tissue Mg concentrations remained unchanged. The sedentary old group exhibited a significant decrease in kidney Cu concentration compared to the young control group (p<0.01). Although kidney Cu levels also decreased in trained old rats in comparison to young controls (p<0.05), they were significantly higher than in sedentary old rats (p<0.01). The decrease in kidney Zn and Cu content as a result of aging was partly prevented by long-term swimming exercise.     

High fructose intake significantly reduces kidney copper concentrations in diabetic, islet transplanted rats

Trace element status is known to be altered in the diabetic state, although the factors affecting trace element homeostasis in this condition are not well understood. The authors examined the effects of a high fructose diet (40% wt:wt) vs a control diet on the copper (Cu), zinc (Zn), and iron (Fe) concentrations in the kidney, plasma, and red blood cells of islet transplanted (TX) and shamoperated (SHAM) rats. Male, Wistar Furth rats made diabetic by streptozotocin injection (55 mg/kg, iv) were given an intraportal islet transplant (1000 islets); control animals were shaminjected, shamoperated (SHAM). Rats within TX and SHAM groups were assigned to either a high fructose diet (40% fructose, 25% cornstarch, FR) or a purified control diet (33% cornstarch, 33% dextrose, CNTL) containing identical amounts of mineral mixture for a period of 6 wk. Kidney Cu concentration was significantly elevated among hyperglycemie TXCNTL rats (224 ± 25 nmol/g wet wt), but was markedly reduced in hyperglycemic TXFR rats (109 ± 14 nmol/g) relative to normoglycemic controls. This occurred in spite of similar levels of glucose, insulin (fed and fasted), insulin secretory capacity, body weight, and food intake in the TXCNTL and TXFR groups. Among the subgroup of rats with normal glucose levels post-TX, kidney Cu levels normalized and were unaffected by dietary treatment (normoglycemic TXCNTL = 60 ± 5 nmol/g; normoglycemic TXFR = 40 ± 2 nmol/g). Kidney Cu concentrations also were unaffected by fructose feeding in SHAM animals (CNTL, 60 ± 4 nmol/g and FR, 51 ± 5 nmol/g). Kidney Zn and Fe concentrations were similar among the treatment groups. Plasma and red blood cell (RBC) Cu, Zn, and Fe concentrations were also similar among the groups. Since fructose feeding led to a substantial reduction of kidney Cu concentrations in the presence of hyperglycemia, the authors suggest that this model can be useful in examining effects of altered kidney Cu accumulation in the diabetic animal.     

Leucocyte copper, a marker of copper body status is low in coronary artery disease

To elucidate the relationship between leucocyte copper as a reliable, sensitive index of copper body status and extent of atherosclerosis in patients with Coronary Artery Disease (CAD) the present case-control study was carried out. 80 subjects were studied (23 females and 57 males), aged between 30-70, due to have a angiography. Individual angiograms were scored by combining the individual scores in all the major coronary arteries into one score of a scale 1.00 for patency to 0.00 for severe CAD. Serum and leucocyte copper and zinc were determined by GFAAS. No significant difference between patients with advanced CAD and relatively normal arteries were observed in the lipid profile and levels of plasma copper. Leucocyte copper had a significant link with the severity of atherosclerosis which was independent of sex. There was a linear relationship between the degree of decreasing leucocyte copper concentration and angiogram score. These findings give support to the hypothesis that marginal copper status, assessed by decreased leucocyte copper level, is associated with developing CAD.     

Effect of medium copper concentration on the growth,uptake and intracellular balance of copper and zinc in Menkes' and normal control cells

The precise nature of the variation in cellular copper load against medium copper concentration is defined using a comprehensive logarithmically incremented series of medium copper concentrations ranging from low levels (4.8 p.p.b.) through normal to toxic levels (40 p.p.m.) in which fibroblasts were grown followed by determination of intracellular content. Menkes' fibroblasts showed an unexpected plateau region of stable intracellular copper content against a change in medium concentration of over 100-fold, albeit only when sufficient copper was present in the medium (0.08–8.0 p.p.m.). Thus, Menkes' cells are clearly capable of balancing uptake/efflux providing copper availability allows. Simultaneous analysis of cellular copper and zinc load at various medium copper concentrations shows an indistinguishable intracellular copper:zinc ratio between the two cell lines. The nature of non-labeled copper uptake by fibroblasts over a 40 min and 7 day period is reported. During the 40 min period copper uptake (20 p.p.m.) was essentially the same in both cell lines. However, copper absorbed was superimposed upon large pre-existing copper pools in the case of Menkes' cells only. Advantages of techniques determining non-labeled copper in copper uptake/efflux experiments are discussed in the light of these results. Fibroblast growth studies showed that, compared with normal cells, Menkes' cells are significantly (P < 0.01) more growth sensitive to extended exposure to low copper concentrations. Thus, Menkes' disease appears to be not only a result of copper maldistribution but also a direct result of an inability of Menkes' cells to function normally in low copper environments.     

Iron and zinc status in rats with diet-induced marginal deficiency of vitamin A and/or copper

The hypothesis was tested that there are interactions of marginal copper and vitamin A deficiency regarding iron and zinc status. Copper restriction (1 vs 5 mg Cu/kg diet) significantly lowered copper concentrations in plasma and tissues of rats and reduced blood hemoglobin, hematocrit, and iron concentrations in tibia and femur, but raised iron concentrations in liver. Vitamin A restriction (0 vs 4000 IU vitamin A/kg diet) reduced plasma retinol concentrations and induced a fall of blood hemoglobin and hematocrit. Neither copper nor vitamin A restriction for up to 42 d affected feed intake and body wt gain. There were no interrelated effects of vitamin A and copper deficiency on iron status. Copper deficiency slightly depressed liver, spleen, and kidney zinc concentrations. Vitamin A deficiency lowered zinc concentrations in heart, but only when the diets were deficient in copper.     

The effect of ethanol on zinc and copper metabolism in rats

Studies performed on adult female rats over a period of 10 weeks indicated that the consumption of alcohol (20% v/v) did not appear to disturb the zinc or copper balance, nor did it adversely affect tissue zinc or copper levels, even in zinc-restricted animals. On the contrary, higher plasma zinc levels were consistently observed in animals receiving alcohol together with the experimental diets.     

Interaction of C20-substituted derivative of pregnenolone acetate with copper (II) leads to ROS generation,DNA cleavage and apoptosis in cervical cancer cells: Therapeutic potential of copper chelation for cancer treatment

Cervical cancer is a leading cause of cancer-related deaths among women in developing countries. Therefore, development of new chemotherapeutic agents is required. Unlike normal cells, cancer cells contain elevated copper levels which play an integral role in angiogenesis. Thus, targeting copper via copper-specific chelators in cancer cells can serve as effective anticancer strategy. In this work, a copper chelator pregnenolone acetate nucleus-based tetrazole derivative (ligand-L) was synthesized and characterized by elemental analysis, ESI-MS, ¹H NMR and ¹³C NMR. DNA binding ability of ligand-L was studied using UV–Vis and fluorescence spectroscopy. Fluorescence spectroscopy studies reveal that quenching constant of ligand-l-DNA and ligand-L-Cu(II) were found to be 7.4 × 10³ M⁻¹ and 8.8 × 10³ M⁻¹, respectively. In vitro toxicity of ligand-L was studied on human cervical cancer C33A cancer cells. Results showed that ligand-L exhibit significant cytotoxic activity against cervical cancer C33A cells with IC₅₀ value 5.0 ± 1.8 µM. Further, it was found that ligand-L cytotoxicity is due to redox cycling of copper to generate ROS which leads to DNA damage and apoptosis. In conclusion, this is the report where we synthesized pregnenolone acetate-based tetrazole derivative against C33A cells that targets cellular copper to induce pro-oxidant death in cancer cells. These findings will provide significant insights into the development of new chemical molecules with better copper chelating and pro-oxidant properties against cancer cells.     

Analysis of the value of copper erythrocyte concentration measurement in the diagnosis of copper deficiency in bovines

BackgroundA reliable and practical method for assessing Cu status in live animals is not available. Blood Cu levels may not accurately reflect the true Cu status of the herd, and can over-predict Cu status during stress and inflammation. On the other hand, assessment of liver Cu is the most reliable indicator of Cu stores, but it is an invasive procedure that requires specialized training. The aim of this study was to evaluate the usefulness of Cu levels in red blood cells to determine the Cu status, with special emphasis in their correlation with erythrocyte Cu, Zn superoxide dismutase enzyme activity (ESOD), in bovines with Cu deficiency induced by high molybdenum and sulfur levels in the diet.MethodsThree similar assays were performed, with a total of twenty eight calves. The Cu-deficient group (n = 15) received a basal diet supplemented with 11 mg of Mo/kg DM as sodium molybdate, and S as sodium sulfate. The control group (n = 13) received a basal diet supplemented with 9 mg of Cu/kg DM as copper sulfate.Samples of blood and liver were taken every 28–35 days. Cu levels were measured in liver (expressed as µg/g DM), plasma (expressed as µg/dl), and erythrocytes (expressed as µg/g Hb) by flame atomic absorption spectroscopy. Superoxide dismutase (SOD1) activity was determined in red blood cells and was expressed as IU/mg hemoglobin.InfoStat Statistical Software 2020 was used for the statistical analysis. Cu levels in plasma, red blood cells and liver, and ESOD activity were analyzed by ANOVA. The correlation between erythrocyte Cu levels and the rest of the parameters were analyzed by Pearson Correlation test. Unweighted Least Squares Linear Regression of SOD1 was developed. The autocorrelation between the monthly measurements was also determined by Durbin-Watson test and autocorrelation function.ResultsThe assays lasted 314–341 days, approximately. Levels indicative of Cu deficiency for bovines were detected at 224 days (23 ± 11.6 µg/g DM) for liver Cu concentration; and at 198 days (55 ± 10.4 µg/dl) for plasma Cu concentration, in Cu-deficient animals. Liver and plasma Cu values indicative of Cu deficiency were not observed in the control group.Pearson Correlation test indicated that all indices of Cu status used in this study were significantly correlated. The highest value was obtained between ESOD and red blood Cu (0.74). There was a significant correlation between red blood Cu and plasma Cu (0.65), and with hepatic Cu (0.57). ESOD activity showed a similar significant positive correlation with liver Cu concentrations and with plasma Cu (0.59 and 0.58, respectively).ConclusionThe extremely low levels of liver and plasma Cu, the ESOD activity, erythrocyte Cu levels, and the periocular achromotrichia observed in the Cu-deficient animals showed that the clinic phase of Cu deficiency was reached in this group. The ESOD activity and erythrocyte Cu levels showed a strong association, indicating that the values of erythrocyte Cu may serve as an effective tool in assessing Cu status and diagnose a long-term Cu deficiency in cattle.     

Effects of acute prednisolone administration on plasma and liver copper in rats with adjuvant arthritis

Several studies in animals and humans have shown that copper metabolism could be affected by inflammation or by corticosteroids. The relative importance of these two factors, often imbedded in clinical practice, was assessed by investigating the effects of acute prednisolone administration (30 mg/kg, ip) on healthy and adjuvant arthritis rats. Plasma copper levels were significantly higher in arthritic rats compared to healthy animals, whereas there was a slight, but nonsignificant increase in liver copper. Acute prednisolone administration in healthy rats resulted in a significant increase in plasma copper (10–15%) as early as 4 h after corticosteroid administration, which was maintained for 12 h. In arthritic rats, the response was much higher (25–40%), but somewhat delayed and shorter. Liver copper was not clearly modified by prednisolone treatment in both groups. This time-controlled study showed that acute prednisolone administration increased plasma copper in both healthy and arthritic rats, but in different ways, indicating that inflammation and corticosteroids may act synergistically.