In the paper we utilized the adsorptive transfer stripping differential pulse voltammetry Brdicka reaction for the determination of metallothioneins (MT) in melanoma cells, animal melanoma tissues (MeLiM miniature pig) and blood serum of patients with malignant melanoma. Primarily we attempted to investigate the influence of dilution of real sample on MT electrochemical response. Dilution of samples of 1 000 times was chosen the most suitable for determination of MT level in biological samples. Then we quantified the MT level in the melanoma cells, the animal melanoma tissues and the blood serum samples. The MT content in the cells varied within the range from 4.2 to 11.2 μM. At animal melanoma tissues (melanomas localized on abdomen, back limb and dorsum) the highest content of MT was determined in the tumour sampled on the back of the animal and was nearly 500 μg of MTs per gram of a tissue. We also quantified content of MT in metastases, which was found in liver, spleen and lymph nodes. Moreover the average MT level in the blood serum samples from patients with melanoma was 3.0 ± 0.8 μM. MT levels determined at melanoma samples were significantly (p < 0.05) higher compared to control ones at cells, tissues and blood serum.

Department of Animal Nutrition and Forage Production Faculty of Agronomy Mendel University of Agriculture and Forestry Zemedelska 1 CZ 613 00 Brno Czech Republic

Department of Chemistry and Biochemistry Faculty of Agronomy Mendel University of Agriculture and Forestry Zemedelska 1 CZ 613 00 Brno Czech Republic

Department of Chemistry Faculty of Science Masaryk University Kotlarska 2 CZ 611 37 Brno Czech Republic

Department of Chemistry University of California One Shields Avenue CA 956 16 Davis USA

Department of Clinical Biochemistry and Pathobiochemistry 2nd Faculty of Medicine Charles University 5 Uvalu 84 CZ 150 06 Prague 5 Czech Republic

Laboratory of Tumour Biology Department of Animal Embryology Cell and Tissue Differentitation Institute of Animal Physiology and Genetics Academy of Sciences of the Czech Republic v v i CZ 277 21 Libechov Czech Republic

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