Vliv carvedilolu na metabolickou aktivitu fagocytů

Bc. Michaela Pekarová, Ph.D.

Master's thesis

The effect of carvedilol on metabolic activity of fagocytes

Abstract:

Produkcia NO makrofágmi bola sledovaná pomocou spektrofotometrického stanovenia nitritov v médiu použitím Griessovej metódy. Western blot bol použitý pri sledovaní expresie iNOS v tejto bunkovej línii RAW 264.7. Toxické účinky testovaných látok na makrofágy boli sledované pomocou ATP celulárneho testu. Potenciálne schopnosti testovaných látok vychytávať oxid dusnatý testované pomocou ampérometrickej detekcie NO. Efekt carvedilolu na makrofágy bol porovnávaný s efektom adrenergických agonistov (adrenalínu, noradrenalínu a dopamínu) a antagonistov (atenololu a prazosinu). Z výsledkov vyplýva, že carvedilol v závislosti na koncentrácii a spôsobe inkubácie, moduloval NO produkciu aj expresiu iNOS v makrofágoch in vitro stimulovaných pomocou LPS. Účinok katecholamínov sa prejavil znížením produckcie NO a expresie iNOS. Kombinované účinky carvedilolu aj katecholamínov sa podarilo zablokovať preinkubáciou buniek s kombináciou atenololu a prazosinu. To naznačuje, že carvedilol aj katecholamíny pôsobili na makrofágy prostredníctvom modulácie signálnych dráh spojených s adrenergickými receptormi.

Abstract:

Expression of the iNOS protein was assessed by Western blot analysis. NO production was monitored by determination of nitrite concentration in harvested medium by Griess reaction. Viability was tested by ATP cellular assay. Potential scavenging effect against NO was detected using a NO analyzer. The effect of carvedilol was compared with the effect of adrenergic agonists (adrenaline, noradrenaline, dopamine) and antagonists (B-blocker, atenolol and A-blocker, prazosine).Carvedilol inhibited the LPS-induced iNOS expression and nitrite production in a dose dependent manner. Tested catecholamines had similar effect on the NO responce like carvedilol. In addition, the inhibitory effect of carvedilol and catecholamines on NO production and iNOS expression, was abrogated by combination of both atenolol and prazosine. This fact indicates that suppresive effect of carvedilol and catecholamines on NO production and also iNOS expression in LPS-stimulated macrophages was probably mediated via modulation of signalling pathways connected with adrenergic receptors.

Keywords

carvedilol, prazosine, atenolol, noradrenaline, adrenaline, macrophages, NO production, iNOS expresion

Language used: Czech

Date on which the thesis was submitted / produced: 21. 5. 2007

Thesis defence

• Date of defence: 4. 6. 2007
• Supervisor: doc. RNDr. Antonín Lojek, CSc.

Masaryk University

Faculty of Science

Master programme / field:
Biology / General Biology