Herbicide acetochlor interferes with proliferation activity of MCF-7 cells enhanced by estradiol.

It is well documented that pesticides used in agricultural processes may have detrimental effects upon human health. Moreover, many of these compounds have been indicated as potential endocrine and reproductive disruptors. In the present study, the ability of herbicide acetochlor to affect a growth of estrogen-sensitive MCF-7 mammary epithelial carcinoma cells was studied using E-screen test. Acetochlor alone did not affect proliferation of MCF-7 cells. Significant inhibition of estradiol-induced (10-14-10-8 M) MCF-7 cell growth by the action of acetochlor (10-5 M) and interaction between these chemicals were observed. Estradiol-stimulated MCF-7 cell proliferation was decreased by 41% of positive control (17ß-estradiol, 10-8 M, 100%) in the presence of acetochlor (10-5 M). Our results demonstrate that acetochlor might interfere with estradiol signaling conducted to altered proliferation activity of MCF-7 cells and might support endocrine disruptive effects of acetochlor.

Coxsackieviral infections involved in aseptic meningitis: a study in Slovakia from 2005 to 2009.

A wide range of diseases is associated with enteroviruses.They are reported to be responsible for viral meningitis, especially in children, but also in adults.This study analysed infection with eight selected coxsackievirus serotypes as the cause of aseptic meningitis in 480 patients in Slovakia from 2005 to 2009,using a quantitative assay for the detection of intrathecal antibodies. Intrathecal production of antibodies against selected coxsackieviruses was proved in 21%of these patients. A significant decrease from 35% in 2005 to 8,5% in 2009 (p=0.004) in the proportion of patients with proven intrathecal production of virus specific antibodies was observed during the study period. We conclude that coxsackievirus B4 was the endemic serotype in Slovakia and was responsible for most cases of coxsackieviral meningitis in the study period.

Ex vivo assessment of protective effects of carvacrol against DNA lesions induced in primary rat cells by visible light excited methylene blue (VL+MB).

Carvacrol belongs to frequently occurring phenolic components of essential oils (EOs) and it is present in many kinds of plants. Biological effect of this phenol derivative on human beings is however not sufficiently known. The present study was undertaken to evaluate the level of VL+MB-induced oxidative DNA lesions in hepatocytes and testicular cells (freshly isolated from control or carvacrol-watered rats) by the modified single cell gel electrophoresis (SCGE). The results showed that carvacrol significantly reduced the level of VL+MB-induced oxidized bases (EndoIII- and Fpg-sensitive sites) only in hepatocytes but not in testicular cells. Chromosomal aberration assay of primary hepatocytes, isolated from control or carvacrol-watered rats did not testify any genotoxic activity of carvacrol. We suggest that in vivo applied synthetic carvacrol, whose antioxidative activity was confirmed by DPPH assay, exhibits primarily a strong hepatoprotective activity against oxidative damage to DNA.

High virologic sustained response for former young intravenous drug users with chronic hepatitis C treated by pegylated interferon-alpha plus ribavirin.

AIMS: The aim of this clinical study was to assess virological response at end-of -treatment (ETR), sustained virological (SVR) and biochemical response in former drug users with chronic hepatitis C treated with PEG-IFN-alpha and R. PATIENTS: Ninety two former drug users (21 F, 71 M) average age 27 years (18 to 41 years) and previously not treated with IFN-alpha and R (naive patients, pts) were evaluated for their virological and biochemical response. Standard treatment regimen of either 24 or 48 weeks was applied in patients with genotype 3 or genotype 1, respectively. SVR was considered if viral tests (HCV RNA) were negative 24 weeks after the end of treatment. RESULTS: Overall SVR was attained in 87 (95%) of 92 treated patients, and therapy failed in 5 pts with genotype 1. In genotype 1 patients ETR and SVR were 81% and 86%, respectively (p < 0.001). In genotype 3 patients ETR and SVR were 98% and 100%, respectively (p < 0.001). ALT levels decreased significantly after 12 weeks of therapy (ALT 1.61 vs 0.64 micro/kat/l, p < 0.001) and were at normal levels during follow-up. CONCLUSIONS: Crucial predictive factors resulting in high SVR were the younger age in combination with low stage of liver fibrosis, relatively short duration of viral infection, high proportion of genotype 3 and excellent adherence of patients to treatment regimen than previously not treated with IFN-alpha and R (naive patients). High proportion of SVR in former drug users has been achieved in patients with genotype 3 (100%) and genotype 1 (86%). The most decisive prognostic factor which favors high therapeutic efficacy appears to be young age and early onset of anti-HCV treatment (Tab. 3, Fig. 1, Ref. 33). Full Text (Free, PDF) www.bmj.sk.

Effects of borneol on the level of DNA damage induced in primary rat hepatocytes and testicular cells by hydrogen peroxide.

The aim of this paper was to evaluate genotoxic effects of borneol and its ability to change DNA-damaging effects of H2O2 in rat hepatocytes and testicular cells. Both in vitro and ex vivo approaches were used in the case of hepatocytes. Testicular cells were tested only ex vivo, i.e. shortly after isolation from rats supplemented by borneol. Cytotoxicity of borneol increased in in vitro conditions in a concentration-dependent manner and it was associated with DNA-damaging effects at toxic concentrations. While non-toxic concentrations of borneol applied in vitro protected cells against H2O2-induced DNA damage and interfered only partly with rejoining of H2O2-induced DNA strand breaks, cytotoxic concentrations of borneol manifested synergy with H2O2, i.e. enhanced DNA-damaging effects of H2O2. On the other side, borneol given to rats in drinking water decreased the level of DNA damage induced by H2O2 in both hepatocytes and testicular cells. Our results show that though at higher concentrations (2-h treatment with >2 mM borneol >0.3084 mg/ml) borneol acts cytotoxically and genotoxically on primary hepatocytes cultured in vitro, if given to rats during 7 days in a daily concentration of 17.14 or 34.28 mg/kg it reduces genotoxicity of H2O2 in both hepatocytes and testicular cells.

Factors influencing the use of potentially inappropriate medication in older patients in Slovakia.

BACKGROUND: Although increasing attention has been given to the evaluation of use of potentially inappropriate medication in the older European Union (EU) member countries, information on this topic from Central and Eastern Europe is scarce. OBJECTIVES: The aims of the present study were: to identify risk factors enhancing the probability of use of potentially inappropriate medication in hospitalized older patients under the conditions of the Slovak healthcare system and to compare our results with previously published European studies. METHODS: The evaluation was performed in 600 patients aged > or =65 years, hospitalized in a general hospital between 1 December 2003 and 31 March 2005. To identify the use of potentially inappropriate medication, the Beers 2003 criteria were applied. Particular socio-demographic and clinical characteristics, as well as comorbid medical conditions were evaluated among possible factors enhancing the probability of use of potentially inappropriate medication. RESULTS: At least one potentially inappropriate medication was prescribed to 126 (21%) of 600 patients. Multivariate analysis identified polypharmacy [odds ratio (OR) 2.38; 95% confidence interval (CI): 1.50-3.79], depression (OR 2.03; 95% CI: 1.08-3.82), immobilization (OR 1.87; 95% CI: 1.16-3.00) and heart failure (OR 1.73; 95% CI: 1.13-2.64) as factors associated with an increased risk of use of inappropriate medication. In contrast, patients aged > or =75 years had a lower risk of being prescribed potentially inappropriate medication (OR 0.58; 95% CI: 0.39-0.88). CONCLUSIONS: Polypharmacy, immobilization, heart failure and depression were documented as predictors of use of potentially inappropriate medication. In depressive patients, drugs other than antidepressants contributed to the extensive use of potentially inappropriate medication. The observed prevalence of use of potentially inappropriate medication in older hospitalized Slovak patients was lower than the prevalence previously documented in Poland and the Czech Republic, but higher than in Croatia and Turkey. The identified risk factors were consistent with previous findings from other parts of Europe.

Carvacrol given to rats in drinking water reduces the level of DNA lesions induced in freshly isolated hepatocytes and testicular cells by H(2)O(2).

Carvacrol represents a very frequent constituent of essential oils and occurs in many kinds of plants. Though human beings comequite often into close contact with this phenol derivative, its biological effects are not sufficiently known. In this paper we investigated the influence of carvacrol given to rats in drinking water on resistance of their liver and testicular DNA against the oxidative agent hydrogen peroxide H(2)O(2). Carvacrol was dissolved in tap water and given to rats either in concentrations of 30 and 60 mg/1 kg/day during 7 days or in concentrations of 15 and 30 mg/1 kg/day during 14 days. Control animals were given tap water only. After the given time the rats were sacrificed and hepatocytes and testicular cells were isolated and treated with different concentrations of H(2)O(2) (0-250 microM, 5 min, on ice). Then the level of DNA lesions was detected by single cell gel electrophoresis. The results of both types of application of carvacrol showed that DNA of cells isolated from carvacrol-treated animals was significantly more resistant to damaging effects of hydrogen peroxide than DNA of control animals. We assume that the observed DNA-protective effects of carvacrol, which was given to rats during a short time of their life, could be associated with an increase of antioxidant activity of liver and testicular cells in these animals.

Perception of potentially inappropriate medication in elderly patients by Slovak physicians.

PURPOSE: The aim of the present study was to determine the risk perception of potentially inappropriate drug treatment of elderly patients by Slovak physicians. In Slovakia, a list of such drugs is not available. METHODS: The study sample consisted of 600 patients aged > or =65 years hospitalized at the Department of Internal Medicine in a Slovak general hospital between 1 December 2003 and 31 March 2005. The use of potentially inappropriate drugs at the time of hospital admission and discharge was compared. Potentially inappropriate drug use was defined by Beers 2003 criteria. In addition, 206 physicians were asked to mark the drugs that they considered potentially inappropriate for elderly patients out of a list provided in a questionnaire analysis. RESULTS: Out of 600 patients 20.2% and 20% were treated with at least one potentially inappropriate drug at the time of hospital admission and discharge, respectively. Hospitalization had no significant influence on the number of potentially inappropriate medicines used. The most frequently prescribed potentially inappropriate drugs were digoxin >0.125 mg/day and ticlopidine. Out of 206 responding physicians only 4.9% considered ticlopidine as potentially inappropriate for elderly patient. On the other hand, more than 20% of respondents were aware of the potential inappropriateness of amitriptyline, diazepam and chlordiazepoxide. Mentioned drugs were observed in less than 2% of study population (n = 600). CONCLUSIONS: The results of the questionnaire analysis in physicians as well as the prevalence of potentially inappropriate medication demonstrate that Slovak clinicians are aware of the risk of certain treatments in elderly patients.

Creutzfeldt-Jakob disease risk and PRNP codon 129 polymorphism: necessity to revalue current data.

The polymorphism at codon 129 (M129V) of the prion protein gene (PRNP) is a recognized genetic marker for susceptibility to Creutzfeldt-Jakob disease (CJD) in the Caucasians. The distribution of this polymorphism in healthy individuals provides an important starting point for the evaluation of CJD risk in the general population. Early studies of reference population cohorts demonstrated that methionine/valine heterozygosity was the most frequent genotype. These studies were performed in relatively small numbers of control subjects and do not correspond with the findings of more recent investigations. In this study, we present an analysis of the codon M129V distribution in 613 corneal donors, representing one of the largest control groups examined to date. Methionine homozygotes represented 48.1%, valine homozygotes 8.7% and methionine/valine heterozygotes 43.2%. While age-related difference was not significant, differentiation according to the gender showed significant difference. The observed highest proportion of methionine homozygotes and statistically significant difference between genders as well as comparison with results obtained in other countries underline the need to re-evaluate the generally used reference data on M129V, including consideration of the gender, age and geographical distribution.

Antioxidant supplementation reduces inter-individual variation in markers of oxidative damage.

The aim of this study was to examine the effect of antioxidant supplementation on oxidative damage and chromosome stability in middle-aged men, smokers and non-smokers. A total of 124 men aged 48+/-6 years from Bratislava and from the rural population near Bratislava were investigated; 64 men (22 smokers and 42 non-smokers) were supplemented for 12 weeks with antioxidants, while 60 (25 smokers and 35 non-smokers) were given placebo. The daily antioxidant supplementation consisted of vitamin C (100 mg), vitamin E (100 mg), ss-carotene (6 mg), and selenium (50 microg). Samples of blood were taken on two occasions: At the beginning and at the end of the supplementation trial. Concentrations of dietary antioxidants, ferric reducing ability, malondialdehyde as an indicator of lipid peroxidation in plasma, micronuclei and chromosome aberrations in lymphocytes were measured. Antioxidant supplementation significantly increased the levels of vitamin C, ss-carotene, a-tocopherol and selenium in plasma. The overall antioxidant status of plasma measured as ferric reducing ability of plasma (FRAP) increased significantly (p<0.001) after antioxidant supplementation as well. The increase in antioxidant parameters after supplementation were consistently more pronounced in non-smokers than in smokers. There was a significant decrease of malondialdehyde concentration in the non-smokers, while in smokers the decrease of malondialdehyde concentration was not significant. Antioxidant supplementation did not affect the proportion of lymphocytes with micronuclei or the total number of micronuclei; however, there was a significant positive correlation (p<0.001) between the malondialdehyde concentration at the beginning of the supplementation trial and the difference in number of cells with micronuclei before and after the supplementation. The percent of cells with chromosome aberrations decreased significantly after antioxidant supplementation in smokers. These results indicate that a combined antioxidant supplementation (a) is effective even at very moderate doses; (b) significantly diminishes oxidative damage to lipids when it is high initially; and (c) is effective in decreasing chromosomal instability in lymphocytes of middle-aged men.

Spontaneous and gamma-ray-induced sister chromatid exchanges in patients with carcinoma of cervix uteri.

The aim was to investigate whether there are differences in the spontaneous and gamma-ray-induced genomic instability in peripheral blood lymphocytes between untreated cervical cancer patients and healthy women using the sister chromatid exchange (SCE) assay as an indicator of chromosomal instability. Lymphocyte cultures from whole venous blood of 10 patients with cervical neoplasia and 10 healthy female volunteers were cultivated in vitro and irradiated using a 60Co-gamma source. Slides were prepared using the standard air-drying procedure and stained by the fluorescence-plus Giemsa (FPG) technique. The number of SCE and the number of chromosomes were assessed in second-division metaphases. A radiation dose-dependent increase of SCE/cell and SCE/chromosome values were found in healthy women as well as in patients, while statistical analysis has shown significantly higher SCE frequencies in healthy women as compared with patients. Cellular kinetics expressed as replication indices (RI) calculated from the frequency of cells in first cell division (M1), second cell division (M2) and third cell division (M3) were also significantly different, while observed RI were higher for patients than for control individuals. The results suggest that patients with carcinoma of the cervix uteri have chromosomal stability changes reflected in statistically different levels of spontaneous and induced SCE in comparison with healthy individuals. Despite the unknown mechanisms of SCE formation, it is felt that the changed SCE frequency, especially after mutagen treatment, may be used as a marker of increased cancer risk.

Simultaneous flow cytometric evaluation of phagocytosis and oxidative burst in human polymorphonuclear cells.

Phagocytosis and oxidative burst (OXIBURST) activity of human polymorphonuclear cells (PMNs) has been simultaneously measured directly in whole blood samples. The ingestion of yeast was assessed by the phagocytosis activity (FA) and phagocytosis index (FI), and the respiratory burst of PMNs was determined as dihydroethidine (DHE) oxidation. We received comparable results in the ingestion of yeast cells by PMNs using either light microscopy (77.31+/-7.56) or flow cytometry detection method (78.26+/-5.14). The significant differences (p<0.05) in FI and OXIBURST activity were find in the patients (2.29+/-0.29 and 14.67+/-3.99, respectively) when compared to healthy donors (1.64+/-0.21 and 32.38+/-14.94, respectively). The two-color flow cytometric procedure permits measurement of two different functions of neutrophils in one step. This flow cytometric procedure is simple, rapid and has the potential to be an alternative assay to test leukocyte function. (Fig. 3, Ref: 30.)

Effect of C677T methylenetetrahydrofolate reductase gene polymorphism on plasma homocysteine levels in ethnic groups.

The objective of this study was to examine plasma homocysteine levels and C677T methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in two ethnic groups from Slovakia. The samples consisted of general Slovak-Romany population (68 men and 81 women) from Southwestern Slovakia and the Slovak-Caucasians (174 men and 177 women) who participated in the CINDI project. The homocysteine levels were examined by HPLC, the analysis of MTHFR genotypes was done by PCR. The Slovak-Romany men (12.0+/-5.6 (S.D.) micromol/l) and women (9.2+/-2.6 microol/l) have significantly lower plasma homocysteine levels (p<0.024 and p<0.00001) when compared to Caucasians (13.3+/-5.1 micromol/l in men and 11.3+/-4.3 micromol/l in women). The genetic equilibrium is assumed for the gene frequencies of the MTHFR polymorphism in both samples. The distribution of MTHFR genotypes did not differ between the two populations (TT 13 vs. 10.6 %; CT 46.6 vs. 41.7 %; CC 40.4 vs. 47.7 %, chí(2)2 = 2.315, df=2, ns). The effect of MTHFR genotypes on homocysteine levels was not confirmed in the Slovak-Romanies and TT homozygosity significantly increased plasma homocysteine levels only in Slovak-Caucasians (11.5+/-4.4 micromol/l, ns; vs. 14.8+/-4.8 micromol/l, p 0.002, respectively). To our knowledge, this is the first epidemiological study in the Romany population examining distribution of the MTHFR genotypes and their effect on homocysteine levels. Further studies are needed to establish the variety of cardiovascular risk factors among Romanies in order to evaluate the significance of particular factors.

Repair of oxidative DNA lesions in blood lymphocytes isolated from Sprague-Dawley rats; the influence of dietary intake of lignin.

Living organisms possess a variety of self-protective mechanisms which decrease the free radical attack on DNA and so reduce the risk of cancer. Protection of DNA by endogenous antioxidant systems may be significantly increased by numerous exogenously administered antioxidants. Many of them represent important dietary factors. Biopolymer lignin with its phenolic structure can be included into this group of micronutrients. The aim of the present work was to investigate: 1. the effect of biopolymer lignin, given to Sprague-Dawley (SD) rats in diet, on the level of oxidative DNA lesions induced by oxidative stress in freshly isolated peripheral blood lymphocytes in vitro and 2. the influence of lignin on kinetics of rejoining of DNA strand breaks induced in lymphocytes under these conditions. As model oxidative agents were used H2O2 and visible light in the presence of the photosensitizer Methylene Blue. We found out that dietary intake of lignin caused a significant decrease of H2O2-induced DNA strand breaks and visible light-induced oxidative DNA lesions in freshly isolated rat lymphocytes, but it did not influence the kinetics of rejoining of DNA strand breaks.

Nutritional supplementation with antioxidants decreases chromosomal damage in humans.

In order to investigate the effects of antioxidant supplementation on chromosome damage, a 3 month antioxidant supplementation trial was conducted on groups of 28 myocardial infarction survivors and 57 rural controls, all male. The supplement consisted of vitamin C (100 mg/day), vitamin E (100 mg/day), beta-carotene (6 mg/day) and selenium (50 microg/day). Dietary antioxidants in plasma were measured, as well as the ferric reducing ability of plasma (a measure of total plasma antioxidant status) and the concentration of malondialdehyde as an indicator of oxidative stress. Lymphocytes collected at the beginning and end of the supplementation period were stimulated to proliferate and metaphases accumulated for scoring of chromosome aberrations: per cent aberrant cells and chromatid and chromosome breaks. Supplementation with antioxidants was associated with a decrease in the percentage of cells with chromosome aberrations in the group of rural controls (0.63% before compared with 0.27% after supplementation; P = 0.03). The largest effect of supplementation was seen in smokers in this group (0.12% aberrant cells in supplemented compared with 0.81% in placebo group; P > 0.001). The results support the hypothesis that antioxidants decrease genetic damage.

DNA damage and antioxidants; fluctuations through the year in a central European population group.

Dietary antioxidant levels in the blood depend on intake of fruits and vegetables and therefore might be expected to show seasonal variation. A group of healthy male subjects in Bratislava, Slovakia gave blood samples each month for 1 year. Vitamin C, alpha- and gamma-tocopherol and several carotenoids were measured in plasma, and concentrations of essential metals zinc, copper and selenium in serum. Oxidative DNA damage was assessed in lymphocytes using the comet assay. Seasonal variations in antioxidant levels did not follow a common pattern. beta-Cryptoxanthin was highest in the spring. Lycopene peaked in late summer. Lutein/zeaxanthin was higher in summer than in winter. The concentration of zinc in serum was higher in winter than in summer. DNA damage was lower in summer than in winter. Selenium as well as several antioxidants correlated negatively with indices of DNA damage, while zinc levels showed a positive correlation with DNA damage. These results provide some support for a link between consumption of antioxidants and protection against DNA oxidation.

Lactate dehydrogenase activity in human placenta following exposure to environmental pollutants.

The impact of environmental pollution at the place of residence of pregnant women and of their smoking habits on the cellular energy metabolism of placental tissue was investigated. Samples of full-term placentas were randomly collected from two environmentally different regions of Slovakia (Bratislava, Stará Lubovna) and the activity of lactate dehydrogenase (LDH) was measured. Our results showed enhanced LDH activity in the placenta that was dependent on both the type of environmental pollutants at the place of residence and the smoking habits during pregnancy. The enhanced LDH activity may reflect hypoxic conditions due to the accumulation of heavy metals and toxic compounds of tobacco smoke in the placental tissue. A high content of heavy metal particles, found in placental samples from Stará Lubovna in our previous studies, might contribute to the increased LDH activity in placentas from this region. We hypothesize that fine metal particles deposited in the placental tissue might be phagocytozed by the syncytiotrophoblast, thus contributing to the decreased oxygen level in placental tissue.

Bile analysis as a tool for assessing integrity of biliary epithelial cells after cold ischemia--reperfusion of rat livers.

Previous morphological studies failed to show appreciable injury of biliary epithelial cells (BEC) after cold ischemia of rat liver, although recent evidence indicated that BEC integrity and function were impaired in this model. We tested the hypothesis that analysis of bile for enzymes, such as lactate dehydrogenase (LDH), alanine transaminase (ALT), and aspartate transaminase (AST), can be used for assessing cold ischemic injury of BEC. Furthermore, we examined whether biliary gamma-glutamyltransferase (GGT) reflects warm ischemic injury of BEC and whether normothermic reperfusion aggravates the negative effect of cold ischemia on BEC integrity and function. Rat livers were reperfused after different periods of cold or warm ischemia using a blood-free perfusion model. Compared with controls, perfusate LDH, ALT, and AST levels and parameters of hepatocyte function, including hepatocyte tight junction permeability, were not significantly altered by 18-h cold ischemia. On the other hand, 9-h cold ischemia markedly increased biliary LDH, ALT, and AST levels. However, only LDH release into the bile was strongly dependent on the time of cold storage. Biliary GGT, LDH, and glucose levels decreased during the reperfusion period following 18-h cold ischemia. The results suggest that biliary LDH can be used for assessing injury of BEC in cold-preserved livers and that normothermic reperfusion does not aggravate preservation-induced injury of BEC after cold ischemic storage.

Comparison of three in vitro assays at evaluation of IC50 of acetylsalicylic acid, ferrous sulfate, amitriptyline, methanol, isopropanol and ethylene glycol in human cancer cells HeLa.

Evaluation of the 50% inhibitory concentration (IC50) of acetylsalicylic acid, ferrous sulfate, amitriptyline, methanol, isopropanol and ethylene glycol was done on human cancer cells cultured in in vitro conditions. Three different in vitro assays were used in this study: the plating efficiency test, the microprotein test and the neutral red uptake test. Obtained results were evaluated by statistical methods. All used methods seem to be useful for screening a cytotoxic potential of the tested chemicals. The knowledge of cytotoxic effects of frequently used chemicals on mammalian cells is important not only for necessary in vitro genotoxicity and carcinogenicity studies but also for assessing the toxicity of chemicals to find out possible hazards to the human health. Results presented in this paper underline the usefulness of the wider methodological approach for the comparison of the different endpoints as well as a necessity for selection of a battery of in vitro cytotoxicity tests allowing to estimate the possible harmful effects of xenobiotics.

A rapid, simple, and cost-effective method for screening liver preservation solutions in the rat.

BACKGROUND: Rat liver transplantation models or isolated liver perfusion models are currently used for assessing efficacy of liver preservation methods. We tested the hypothesis that hepatocellular enzymes released into the washout solution after preservation may predict hepatic function during reperfusion and could thus be alternatively used for evaluating efficiency of liver preservation solutions. Furthermore, we applied this approach for assessing the role of Kupffer cells (KC) in preservation-induced liver damage. METHODS: After preservation in University of Wisconsin (UW) or Euro-Collins (EC) solution, rat livers were washed with Ringer-lactate solution. Correlations between enzymes released into the washout solution and hepatocyte functional parameters determined during reperfusion on using a blood-free perfusion model were investigated. RESULTS: In UW-preserved livers, acid phosphatase (ACP) activity correlated negatively with bile flow (R = -0.904), taurocholate intrinsic clearance (R = -0.841), and bromosulfophthalein excretion (R = -0.831). Both alanine transaminase and aspartate transaminase activities correlated with the functional parameters investigated. In EC-stored livers, correlation was also found between ACP activity and bile flow (R = -0.666). Livers stored in UW solution exhibited approximately 3 times lower washout activities of enzymes studied than livers stored in EC solution. Mitochondria isolated from UW-stored livers exhibited significantly better function than those isolated from EC-stored livers. Blockade of KC did not influence enzyme release into the washout solution. CONCLUSIONS: Determination of ACP, alanine transaminase, and aspartate transaminase activities in the washout solution can be used as a rapid, simple, and cost-effective way for screening liver preservation solutions. The results also suggest that KC were not involved in preservation-induced liver damage.