Oral administration of ammonium metavanadate and potassium dichromate distorts the inflammatory reaction induced by turpentine oil injection in male rats.

Heavy metal pollution is rapidly increasing in the environment. It has been shown that exposure to vanadium and chromium is able to alter the immune response. Nevertheless, the mechanisms by which these metal pollutants mediate their immunomodulatory effects are not completely understood. Herein, we examined the effect of ammonium metavanadate and potassium dichromate on the development of an inflammatory response caused by subcutaneous injection of turpentine oil. We demonstrated that pretreatment of rats with ammonium metavanadate and potassium dichromate for two weeks prior to initiation of the inflammatory response resulted in a wider zone of necrosis surrounding the site of inflammation. The acute inflammatory process in the combined model was characterized by elevated serum levels of IL-10 and decreased serum levels of IL-6 as compared to rats not treated with ammonium metavanadate and potassium dichromate. Ammonium metavanadate and potassium dichromate administration induced a decrease in the proportion of splenic His48HighCD11b/c+ myeloid cells accompanied by a reduced infiltration of the wound with neutrophils. Further analysis showed decreased proportions of CD3+CD4+IFNγ+ and CD3+CD4+IL-4+ T cells in the rats with combined model as compared to inflamed rats not treated with ammonium metavanadate and potassium dichromate. The data suggest that consumption of vanadium and chromium compounds disrupts the inflammatory response through an altered balance of pro- and anti-inflammatory cytokines and inhibition of effector T cell activation and neutrophil expansion.

Suitable test concentration of cobalt and concomitant reactivity to nickel and chromium: A multicentre study from the Swedish Contact Dermatitis Research Group.

BACKGROUND: In Sweden, cobalt chloride 0.5% has been included in the baseline series since the mid-1980s. A recent study from Stockholm showed that cobalt chloride 1% petrolatum (pet.) was more suitable than 0.5%. Cobalt chloride at 1.0% has been patch tested for decades in many European countries and around the world. OBJECTIVES: To study the suitability of patch testing to cobalt 1.0% vs 0.5% and to analyze the co-occurrence of allergy to cobalt, chromium, and nickel. RESULTS: Contact allergy to cobalt was shown in 90 patients (6.6%). Eighty (5.9%) patients tested positive to cobalt 1.0%. Thirty-seven of the 90 patients (41.1%) with cobalt allergy were missed by cobalt 0.5% and 10 (0.7%) were missed by cobalt 1.0% (P < .001). No case of patch test sensitization was reported. Allergy to chromium was seen in 2.6% and allergy to nickel in 13.3%. Solitary allergy to cobalt without nickel allergy was shown in 61.1% of cobalt-positive individuals. Female patients had larger proportions of positive reactions to cobalt (P = .036) and nickel (P < .001) than males. CONCLUSION: The results speak in favor of replacing cobalt chloride 0.5% with cobalt chloride 1.0% pet. in the Swedish baseline series, which will be done 2021.

Effects of the Oral Administration of K2Cr2O7 and Na2SeO3 on Ca, Mg, Mn, Fe, Cu, and Zn Contents in the Heart, Liver, Spleen, and Kidney of Chickens.

This study aimed to investigate the effects of selenium on the ion profiles in the heart, liver, spleen, and kidney through the oral administration of hexavalent chromium. Approximately 22.14 mg/kg b.w. K2Cr2O7 was added to water to establish a chronic poisoning model. Different selenium levels (0.00, 0.31, 0.63, 1.25, 2.50, and 5.00 mg Na2SeO3/kg b.w.) around the safe dose were administered to the experimental group model. Ca, Mg, Mn, Fe, Cu, and Zn were detected in the organs through flame atomic absorption spectrometry after these organs were exposed to K2Cr2O7 and Na2SeO3 for 14, 28, and 42 days. Results showed that these elements exhibited various changes. Ca contents declined in the heart, liver, and spleen. Ca contents also decreased on the 28th day and increased on the 42nd day in the kidney. Mn contents declined in the heart and spleen but increased in the kidney. Mn contents also decreased on the 28th day and increased on the 42nd day in the liver. Cu contents declined in the heart and spleen. Cu contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Zn contents declined in the heart and spleen. Zn contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Fe contents decreased in the heart and liver. Fe contents increased on the 28th day and decreased on the 42nd day in the spleen and kidney. Mg contents did not significantly change in these organs. Appropriate selenium contents enhanced Mn and Zn contents, which were declined by chromium. Conversely, appropriate selenium contents reduced Ca, Fe, and Cu contents, which were increased by chromium. In conclusion, the exposure of chickens to K2Cr2O7 induced changes in different trace elements, and Na2SeO3 supplementation could alleviate this condition.

Oxidative Stress Markers and Histological Analysis in Diverse Organs from Rats Treated with a Hepatotoxic Dose of Cr(VI): Effect of Curcumin.

Hexavalent chromium [Cr(VI)] compounds are extremely toxic and carcinogenic. Despite the vast quantity of reports about Cr(VI) toxicity, the information regarding its effects when it is intraperitoneally (i.p.) administered is still limited. In contrast, it has been shown that curcumin prevents hepatotoxicity induced by a single intraperitoneal injection of 15 mg/kg body weight (b.w.) of potassium dichromate (K2Cr2O7). This study aims to evaluate oxidative stress markers, the activity of antioxidant enzymes, and the potential histological injury in brain, heart, lung, kidney, spleen, pancreas, stomach, and intestine from rats treated with a hepatotoxic dose of K2Cr2O7 (15 mg/kg b.w.), and the effect of curcumin pretreatment. Rats were divided into four groups: control, curcumin, K2Cr2O7, and curcumin+K2Cr2O7. At the end of the treatment, plasma and ascites fluid were collected and target organs were dissected out for biochemical and histological analysis. K2Cr2O7 induced hepatotoxicity but failed to induce in all the other studied organs either oxidative or histological injury, since levels of malondialdehyde (MDA), glutathione (GSH), and the activity of superoxide dismutase (SOD), catalase (CAT), and related GSH enzymes were unchanged. As expected, curcumin was safe. Lack of K2Cr2O7-induced toxicity in those target organs could be due to the following: (1) route of administration, (2) absorption through the portal circulation, (3) lower dose than needed, (4) short time of exposure, or (5) repeated doses are required to produce damage. Thus, the intraperitoneal injection of 15 mg/kg of K2Cr2O7, that is able to induce hepatotoxicity, was unable to induce histological and oxidative damage in other target organs.

Edaravone mitigates hexavalent chromium-induced oxidative stress and depletion of antioxidant enzymes while estrogen restores antioxidant enzymes in the rat ovary in F1 offspring.

Environmental contamination of drinking water with chromium (Cr) has been increasing in more than 30 cities in the United States. Previous studies from our group have shown that Cr affects reproductive functions in female Sprague Dawley rats. Although it is impossible to completely remove Cr from the drinking water, it is imperative to develop effective intervention strategies to inhibit Cr-induced deleterious health effects. Edaravone (EDA), a potential inhibitor of free radicals, has been clinically used to treat cancer and cardiac ischemia. This study evaluated the efficacy of EDA against Cr-induced ovarian toxicity. Results showed that maternal exposure to CrVI in rats increased follicular atresia, decreased steroidogenesis, and delayed puberty in F1 offspring. CrVI increased oxidative stress and decreased antioxidant (AOX) enzyme levels in the ovary. CrVI increased follicle atresia by increased expression of cleaved caspase 3, and decreased expression of Bcl2 and Bcl2l1 in the ovary. EDA mitigated or inhibited the effects of CrVI on follicle atresia, pubertal onset, steroid hormone levels, and AOX enzyme activity, as well as the expression of Bcl2 and Bcl2l1 in the ovary. In a second study, CrVI treatment was withdrawn, and F1 rats were injected with estradiol (E2) (10 µg in PBS/ethanol per 100 g body weight) for a period of 2 wk to evaluate whether E2 treatment will restore Cr-induced depletion of AOX enzymes. E2 restored CrVI-induced depletion of glutathione peroxidase 1, catalase, thioredoxin 2, and peroxiredoxin 3 in the ovary. This is the first study to demonstrate the protective effects of EDA against any toxicant in the ovary.

EPR detection of paramagnetic chromium in liver of fish (Anguilla anguilla) treated with dichromate(VI) and associated oxidative stress responses-contribution to elucidation of toxicity mechanisms.

The impact of chromium (Cr) on fish health has been the subject of numerous investigations, establishing a wide spectrum of toxicity, attributed particularly to the hexavalent form [Cr(VI)]. However, reports on the simultaneous assessment of Cr toxicity in fish and its toxico-kinetics, namely involving metal speciation, are scarce. Therefore, keeping in view the understanding of the mechanisms of Cr(VI) toxicity, this work intended to detect the formation of paramagnetic Cr species in liver of Anguilla anguilla following short-term dichromate(VI) intraperitoneal treatment (up to 180 min), assessing simultaneously the pro-oxidant properties. The formation of Cr(V) and Cr(III) was examined by electron paramagnetic resonance (EPR), as an innovative approach in the context of fish toxicology, and related with the levels of total Cr. Cr(V) was successfully detected and quantified by EPR spectrometry, showing a transient occurrence, mostly between 15 and 90 min post-injection, with a peak at 30 min. The limitations of EPR methodology towards the detection and quantification of Cr(III) were confirmed. Although Cr(VI) exposure induced the antioxidant system in the eel's liver, the oxidative deterioration of lipids was not prevented. Overall, the results suggested that Cr(V), as a short-lived species, did not appear to be directly and primarily responsible for the cellular damaging effects observed, since stress responses persisted up to the end of exposure regardless Cr(V) drastic decay. Though further research is needed, ROS mediated pathways (suggested by superoxide dismutase and catalase activity induction) and formation of Cr(III) complexes emerged as the most plausible mechanisms involved in Cr(VI) toxicity.

Effects of hexavalent chromium on reproductive functions of male adult rats.

Hexavalent chromium is an environmental contaminant which may be associated with reproductive abnormalities in male rats. In the present study, we examined the effect of hexavalent chromium on male reproductive function of rats. Male Wistar rats received a daily intraperitoneal injection of potassium dichromate (1 or 2 mg/kg body weight) for fifteen consecutive days. A decrease in testis weight and an increase in seminal vesicles and prostate weights were demonstrated after chromium treatment. Moreover, a dose-dependent increase in blood and testis chromium levels as well as an increase in FSH and a decrease in LH and testosterone serum levels were detected in treated rats. Histological analysis revealed pronounced morphological alterations with enlarged intracellular spaces, tissue loosening and dramatic loss of gametes in the lumen of the seminiferous tubules of treated rats. In addition, a decreased sperm motility and number of epididymal spermatozoa together with an increased sperm abnormality rate was found in chromium-treated rats in comparison to controls. In rats receiving the higher chromium dose, histological images presented considerably increased areas filled with seminal vesicle and prostate secretions. The mucosal crypts of seminal vesicles and the typical invaginations of prostate were altered. The results suggest that subacute treatment of potassium dichromate promotes reproductive system toxicity and affects testicular function of adult male rats.

Caffeic acid inhibits chromium(VI)-induced oxidative stress and changes in brush border membrane enzymes in rat intestine.

We have previously shown that a single oral dose of potassium dichromate results in a decrease in the activities of several brush border membrane enzymes, produces oxidative stress, and alters the activities of several antioxidant enzymes in the small intestine of rats. In the present study, we have investigated the effect of treatment with the dietary antioxidant caffeic acid on potassium dichromate-induced biochemical changes in the rat intestine. Adult male Wistar rats were randomly divided into four groups: control, potassium dichromate alone, caffeic acid alone, and potassium dichromate + caffeic acid. Administration of a single oral dose of potassium dichromate alone (100 mg/kg body mass) led to a decrease in the activities of brush border membrane enzymes, increase in lipid peroxidation, decrease in sulfhydryl groups, and changes in the activities of several antioxidant enzymes. Two oral doses of caffeic acid (each of 250 mg/kg body mass) greatly attenuated the potassium dichromate-induced changes in all these parameters, but the administration of caffeic acid alone had no effect. Thus, caffeic acid is an effective agent in reducing the effects of potassium dichromate on the intestine and could prove to be useful in alleviating the toxicity of chromium(VI) compounds.

Oxidative stress induced by chromium (VI) in bone of suckling rats.

Exposure to hexavalent chromium Cr(VI) compounds is of concern in many Cr-related industries and their surrounding environments. K(2)Cr(2)O(7) is widely recognized as an animal and human carcinogen, mutagen, and teratogen. The present study investigated the bone maturity of suckling rats whose mothers were treated with K(2)Cr(2)O(7). Experiments were carried out on female Wistar rats given 700 ppm of K(2)Cr(2)O(7) in their drinking water from the 14th day of pregnancy until day 14 after delivery. Exposing dams to K(2)Cr(2)O(7) caused disorders in the bone of their progeny. As corollary to this, malondialdehyde levels increased, while glutathione, a non-protein thiol and vitamin C decreased. Alteration of the antioxidant system in the treated group was also confirmed by the significant decline of superoxide dismutase, catalase, and glutathione peroxidase activities. Furthermore, K(2)Cr(2)O(7) induced changes in bone mineralization, especially calcium and phosphorus levels, which decreased. Whereas, in plasma and urine, they increased and decreased inversely. These results suggest that K(2)Cr(2)O(7) accelerated bone resorption activity. In fact, in treated pups, total tartrate-resistant acid phosphatase, which reflected bone resorption, was enhanced while total alkaline phosphatase, which reflected bone formation, was reduced. The impairment of bone function was corresponded histologically.

[Humoral immune response in experimental animals exposed to organic and inorganic compounds].

A humoral immune response was studied in the Wistar rats and (CBAxC57B16)F1 mice orally given potassium bichromate, benzene, and their mixture with drinking water. The test substances were found to have an immunosuppressive effect on both the parameters of an immune response and the level of lysozyme in the experimental animals, which appeared as reductions in the number of splenocytes in the rats, the relative count of antibody-forming cells in the mice, the absolute count of AFC on the spleen in the rats and mice, the level of hemagglutinins in the rats, and that of lysozyme in the rats and mice. Benzene and a mixture of benzene and potassium bichromate showed the most marked immunosuppressive effect on these animals.

Levaduras autóctonas con capacidad fermentativa en la producción de etanol a partir de pulpa de excedentes de plátano musa (AAB Simmonds) en el departamento de Córdoba, Colombia / Autoctonous yeasts having fermentation ability in producing ethanol from Musa (AAB Simmonds) plantain surplus pulp in the Córdoba department of Colombia

Se evaluó la capacidad fermentativa de levaduras nativas de la zona costanera del departamento de Córdoba, Colombia, para la obtención de etanol a partir de la pulpa de excedentes de plátano Musa (AAB Simmonds), con el objetivo de encontrar cepas eficientes. Los microorganismos utilizados correspondieron a las especies: Kloeckera sp, Candida guillliermondii 14AD, Candida albicans y Candida guillliermondii 13AD (nativas), y una cepa comercial de referencia, Saccharomyces cerevisiae T73. La fermentación se realizó a diferentes concentraciones de sustrato, siendo la concentración del 40% la mejor; se evaluó la producción de etanol mediante el método colorimétrico del dicromato de potasio utilizando un equipo espectrofotómetro Lambda 11. Se observó que la levadura Candida guilliermondii 14AD nativa fue la más eficiente con una producción promedio de 3,45% v/v de etanol a las 72 horas de fermentación; no se encontraron diferencias estadísticamente significativas con la producción de etanol a partir de la cepa de referencia, la cual produjo 3,59% v/v. Estos resultados sugieren la existencia de levaduras nativas con capacidad para ser utilizadas en la obtención de etanol a partir de material residuo de plátano.

Native yeasts™ (Cordoba, Colombia) fermentation ability for producing ethanol from plantain (Musa AAB Simmonds) surplus pulp was evaluated; the object was to find efficient yeasts. The microorganisms used here came from the Kloeckera sp, Candida guillliermondii (14AD), Candida albicans and Candida guilllier-mondii 13AD strains (native) and Saccharomyces cerevisiae T73 (a commercial reference yeast). Fermentation was carried out on different substrate concentrations, the 40% one giving the best result; ethanol production was evaluated by the potassium dichromate colorimetric method using a Lambda 11 spectrophotometer. It was observed that the Candida guilliermondii 14AD native yeast was the most efficient, having an average 3.45% v/v ethanol production after 72 hours’ fermentation. There were no statistically significant differences compared to reference yeast strain ethanol production (3.59% v/v). These results suggest that native yeasts can be used in obtaining ethanol from residual plantain matter.

Oral administration of potassium dichromate inhibits brush border membrane enzymes and alters anti-oxidant status of rat intestine.

Potassium dichromate (K2Cr2O7) is a soluble hexavalent chromium compound that is widely used in several industries. In the present work the effect of administration of K2Cr2O7 on rat intestinal brush border membrane(BBM) enzymes and anti-oxidant system was studied. Rats were given a single oral dose of K2Cr2O7 (100 mg/kg bodyweight) and sacrificed 6, 12, 24, 48 and 96 h after the treatment.Control animals were not given K2Cr2O7. The administration of K2Cr2O7 resulted in a reversible decline in the specific activities of several BBM enzymes. The decrease in the activities of these enzymes was due to changes in the maximum velocity while their affinities for the substrates remained unchanged. Lipid peroxidation increased while total SH groups decreased in K2Cr2O7-treated rats as compared to controls indicating increased oxidative stress in the intestinal mucosa. The activities of superoxide dismutase and glutathione-S-transferase increased while those of catalase, glutathione reductase, thioredoxin reductase and glucose-6-phosphate dehydrogenase decreased. The maximum changes in all the parameters studied above were 24 h after administration of K2Cr2O7 after which recovery took place,in most cases almost to control values after 96 h. These results show that oral administration of K2Cr2O7 to decrease in the activities of BBM enzymes, increase in oxidative stress and alters the activities of anti-oxidant enzymes in rat intestine.

Vitamin C attenuates potassium dichromate-induced nephrotoxicity and alterations in renal brush border membrane enzymes and phosphate transport in rats.

BACKGROUND: Exposure to chromium compounds can result in nephrotoxicity. The administration of potassium dichromate (K(2)Cr(2)O(7)), a hexavalent chromium compound, results in impairment in functions of renal brush border membrane (BBM). METHODS: The effect of vitamin C (ascorbic acid) on K(2)Cr(2)O(7)-induced nephrotoxicity, changes in BBM enzymes, Pi transport and the anti-oxidant status of rat kidney were studied. Animals were divided into 4 groups and were intraperitoneally given saline (control), vitamin C alone, K(2)Cr(2)O(7) alone and vitamin C plus K(2)Cr(2)O(7). Nephrotoxicity was evaluated by urea and creatinine levels in the serum. Anti-oxidant status was evaluated in kidney homogenates. RESULTS: A single dose of K(2)Cr(2)O(7) (15 mg/kg body weight) resulted in an increase of serum urea nitrogen and creatinine levels, increase in lipid peroxidation and decrease in total sulfhydryl groups. However, prior treatment with a single dose of vitamin C (250 mg/kg body weight) protected the kidney from the damaging effects of K(2)Cr(2)O(7). It greatly ameliorated the K(2)Cr(2)O(7)-induced nephrotoxicity and reduction in Pi transport, activities of catalase, Cu-Zn superoxide dismutase and BBM enzymes. This was accompanied by decrease in lipid peroxidation and recovery of sulfhydryl content of renal cortex. CONCLUSIONS: Vitamin C is an effective chemoprotectant against K(2)Cr(2)O(7)-induced acute renal failure and dysfunction of the renal BBM in rats.

Oxidative damage produced by Cr(VI) and repair in mussel (Mytilus edulis L.) gill.

This study has assessed DNA damage induced by oxidative stress and its subsequent repair in mussels. Gill was obtained from mussels collected from New Brighton, UK within 24 h and also after 1 month maintenance under laboratory conditions. The pro-oxidant sodium dichromate produced a statistically significant increase in DNA strand breaks (DSB) in these gill cells at both time points as measured by the COMET assay. The response was higher at 1 month in association with a higher concentration of GSH which is known to activate Cr(VI) producing reactive oxygen species. DSB were shown, through studies in wild type and OGG-1-null mouse fibroblasts, to be produced by repair enzymes in response to Cr(VI). In support of evidence for repair of oxidative DNA damage, we have also demonstrated for the first time repair activity in mussel gill towards 8-oxo-dG using an oligonucleotide cutting assay.

Carcinogenic Cr(VI) and the nutritional supplement Cr(III) induce DNA deletions in yeast and mice.

Industrial Cr(VI) emissions contaminate drinking water sources across the U.S., and many people take Cr(III) nutritional supplements. Cr(VI) is a human pulmonary carcinogen, but whether it is carcinogenic in the drinking water is not known. Due to widespread human exposure, it is imperative to determine the carcinogenic potential of Cr(VI) and Cr(III). DNA deletions and other genome rearrangements are involved in carcinogenesis. We determined the effects of Cr(VI) as potassium dichromate and Cr(III) as chromium(III) chloride on the frequencies of DNA deletions measured with the deletion assay in Saccharomyces cerevisiae and the in vivo p(un) reversion assay in C57BL/6J p(un)/p(un) mice. Exposing yeast and mice via drinking water to Cr(VI) and Cr(III) significantly increased the frequency of DNA deletions. We quantified intracellular chromium concentrations in yeast and tissue chromium concentrations in mice after exposure. Surprisingly, this revealed that Cr(III) is a more potent inducer of DNA deletions than Cr(VI) once Cr(III) is absorbed. This study concludes that both the environmental contaminant Cr(VI) and the nutritional supplement Cr(III) increase DNA deletions in vitro and in vivo, when ingested via drinking water.

[In vitro exposure of U937 cells to potassium dichromate: study of apoptosis]. / Esposizione in vitro di cellule U937 a dicromato di potassio: studio dell'apoptosi.

The aim of our study is to evaluate the genotoxic damage of cells treated with different concentrations of potassium dichromate. For this reason we have utilised U937 cells, a cellular line derived from acute promyelocytic leukaemia. Our results show that the minimum concentration of potassium dichromate induces apoptosis in the U937 cells and is of 600 microM, already after 12 hours, the cells treated with potassium dichromate with a concentration of 500 microM presented an apoptosis of 27% while the respective control showed a base apoptosis of 9.5%. Our experimental data indicate that the model adopted by us, may be a valid instrument to study the cytotoxic effects of compounds containing Chromium. In particular we have evidenced a clear genotoxic effect of these compounds demonstrated by a significant increase of the apoptosis percentage which is time and dose dependent.

Influence of potassium dichromate on tracheal secretions in critically ill patients.

BACKGROUND: Stringy, tenacious tracheal secretions may prevent extubation in patients weaned from the respirator. This prospective, randomized, double-blind, placebo-controlled study with parallel assignment was performed to assess the influence of sublingually administered potassium dichromate C30 on the amount of tenacious, stringy tracheal secretions in critically ill patients with a history of tobacco use and COPD. METHODS: In this study, 50 patients breathing spontaneously with continuous positive airway pressure were receiving either potassium dichromate C30 globules (group 1) [Deutsche Homoopathie-Union, Pharmaceutical Company; Karlsruhe, Germany] or placebo (group 2). Five globules were administered twice daily at intervals of 12 h. The amount of tracheal secretions on day 2 after the start of the study as well as the time for successful extubation and length of stay in the ICU were recorded. RESULTS: The amount of tracheal secretions was reduced significantly in group 1 (p < 0.0001). Extubation could be performed significantly earlier in group 1 (p < 0.0001). Similarly, length of stay was significantly shorter in group 1 (4.20 +/- 1.61 days vs 7.68 +/- 3.60 days, p < 0.0001 [mean +/- SD]). CONCLUSION: These data suggest that potentized (diluted and vigorously shaken) potassium dichromate may help to decrease the amount of stringy tracheal secretions in COPD patients.

Protective effect of SnCl2 on K2Cr2O7-induced nephrotoxicity in rats: the indispensability of HO-1 preinduction and lack of association with some antioxidant enzymes.

We have shown that the ameliorative effect of stannous chloride (SnCl2) pretreatment on potassium dichromate (K2Cr2O7)-induced renal damage 24 h after K2Cr2O7 injection was associated with the induction of heme oxygenase-1 (HO-1). In this work we evaluated: (a) if the protective effect of SnCl2 (given 12 h before K2Cr2O7) is associated with changes in the renal activity of HO-1, superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) 24 and 48 h after K2Cr2O7 injection, and (b) if HO-1 induction is indispensable before K2Cr2O7 injection. It was found that the protective effect of SnCl2 on renal function was observed both at 24 and 48 h reaching its maximum at 24 h when HO-1 expression was higher. Cu,Zn-SOD, Mn-SOD, and GR activities remained unchanged whereas GPx and CAT activities decreased at 48 h in K2Cr2O7-treated rats. The activity of Cu,Zn-SOD, Mn-SOD, GPx, CAT, and GR was unchanged in the SnCl2-treated rats. To fulfill the objective (b) groups of rats treated with K2Cr2O7 and SnCl2 (given at the same time or 12 h after K2Cr2O7) were studied 24 h after K2Cr2O7-injection. The simultaneous injections of SnCl2 and K2Cr2O7 had no protective effect whereas the injection of SnCl2 12 h after K2Cr2O7 exacerbated renal damage. In conclusion, the protective effect of SnCl2 on K2Cr2O7-induced nephrotoxicity is associated with HO-1 induction and not with other antioxidant enzymes (Cu,Zn-SOD, Mn-SOD, GPx, GR, and CAT) and SnCl2 has a preventive and not a therapeutic effect on renal damage induced by K2Cr2O7.

[Activity of digestive enzymes during intraperitoneal intake of metal compounds]. / Aktivnost' pishchevaritel'nykh fermentov pri intraperitoneal'nom postuplenii soedinenii metallov.

Digestive function was studied when three compounds from Group VIB of the Mendeleev periodic system of elements were intraperitoneally administered during 100 days. Potassium bichromate, ammonium molybdate in a dose of 0.2 mg/kg and sodium tungstate in a dose of 5.0 mg/kg (in terms of metal) were found to have a resorptive effect on pancreatic function and a local effect on the small intestinal mucosa.