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Lymphocyte DNA damage in rats challenged with a single bout of strenuous exercise

100%

Wierzba T. H., Olek R. A., Fedeli D., Falcioni G.

Journal of Physiology and Pharmacology. Supplement

2006

tom 57

nr 10

115-131

Exercise induces extensive generation of reactive oxygen species, which are responsible for tissue damage: enzymes inactivation, lipid peroxidation and single strand breaks in DNA. Defense system against free radicals is consisting of enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and numerous non-enzymatic antioxidants. The study was performed to evaluate the effect of a single bout of submaximal running exercise, on the lymphocyte DNA strand breaks and also to test how supplementation with tempol – a membrane-permeable SOD-mimetic (0.2 mmol/kg/day) influences the eventually evoked damage. Male, Wistar rats were challenged with graded 50 min. running on treadmill at intensity up to 75-85% of predicted O2 max. The DNA strand breaks in individual lymphocytes were determined by using a gel electrophoretic technique – “comet” assay. We found substantial lymphocyte DNA damage 60 min. after the exercise. Tempol failed to prevent from oxidative damage in rats challenged with exercise. Moreover tempol by itself induced higher DNA damage than the exercise bout.

Effect of tempol on markers of plasma oxidation in rats subjected to prolonged endurance training

100%

Wierzba T. H., Kaldowska A., Ziolowski W.

Acta Biochimica Polonica

2006

tom 53

nr Supplement 1

New bradykinin B2 receptor antagonists - influence of C-terminal segment modifications on their pharmacological properties

64%

Sleszynska M., Kwiatkowska A., Sobolewski D., Wierzba T. H., Katarzynska J., Zabrocki J., Borovickova L., Slaninova J., Prahl A.

Acta Biochimica Polonica

2009

tom 56

nr 4

641-648

In the present study we describe the synthesis and some pharmacological properties of eight new analogues of bradykinin (BK). Two peptides were designed by substitution of position 7 or 8 of the known [d-Arg0,Hyp3,Thi5,8,d-Phe7]BK antagonist (Stewart's antagonist) with l-pipecolic acid (l-Pip). The next two analogues were obtained by replacement of the d-Phe residue in position 7 of the Stewart's peptide with l-β2-isoproline (l-β2-iPro) or l-β3-homoproline (l-β3-hPro). The four analogues mentioned above were also prepared in N-acylated form with 1-adamantaneacetic acid (Aaa). Biological activity of the compounds was assessed by isolated rat uterus and rat blood pressure tests. Our results showed that l-Pip in position 7 slightly increased antagonistic potency in the blood pressure test, but it turned the analogue into an agonist in the rat uterus test. Replacement of Thi by l-Pip in position 8 also enhanced antagonism in the rat pressure test but preserved the antagonism in the rat uterus test. l-β2-iPro or l-β3-hPro in position 7 decreased the potencies in both tests. We also demonstrated that acylation of the N-terminus did not increase, as was claimed previously, the antagonistic potencies of the resulting peptides. The results thus support the hypothesis about the existence of different types of BK receptors in the rat uterus and blood vessels. Our studies provide new information about the structure-activity relationship of BK antagonists which may help in designing more potent BK receptor blockers.

Ograniczanie wyników

2 Acta Biochimica Polonica

1 Journal of Physiology and Pharmacology. Supplement

3 Wierzba T. H.

1 Borovickova L.

1 Falcioni G.

1 Fedeli D.

1 Kaldowska A.

1 Katarzynska J.

1 Kwiatkowska A.

1 Olek R. A.

1 Prahl A.

1 Slaninova J.

1 Sleszynska M.

1 Sobolewski D.

1 Zabrocki J.

1 Ziolowski W.

1 2009

2 2006

Wyniki wyszukiwania

Lymphocyte DNA damage in rats challenged with a single bout of strenuous exercise

Effect of tempol on markers of plasma oxidation in rats subjected to prolonged endurance training

New bradykinin B2 receptor antagonists - influence of C-terminal segment modifications on their pharmacological properties