SciELO - Scientific Electronic Library Online

 
vol.64 issue1Effects of the early administration of losartan on ventricular remodeling in rabbits with experimental myocardial infarctionSurvey on bioethics in a pediatric hospital: Basis for new strategies author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

  • Have no cited articlesCited by SciELO

Related links

  • Have no similar articlesSimilars in SciELO

Share


Medicina (Buenos Aires)

Print version ISSN 0025-7680On-line version ISSN 1669-9106

Abstract

LASCANO, Elena C.; DEL VALLE, Héctor F.  and  NEGRONI, Jorge A.. Effect of different doses of aspirin on preconditioning against stunning in conscious sheep. Medicina (B. Aires) [online]. 2004, vol.64, n.1, pp.30-36. ISSN 0025-7680.

Non-steroid antiinflammatory drugs, inhibitors of cyclooxigenase (COX), have been postulated to have deletereous effects on the heart. Recently, COX-2 inhibitors have also been found to block late preconditioning (LP) protection. Aspirin is the most widely clinically used non-steroid antiinflammatory drug; yet its effect on LP in big mammals has not been determined. It inhibits the two cyclooxigenase isoenzymes (COX-1 and COX-2), at high doses being used as an antiinflammatory drug and at low doses as an antithrombotic agent. The goal of this study was thus, to analyse the effect of different aspirin doses on LP protection against stunning and arrhythmias in a conscious sheep model. The animals were divided in 5 groups: control (C): 12 min ischemia (I)-2 hr reperfusion (R); LP: 6 periods of 5 min I-5 min R, 24 hr before 12 min I, and three groups same as LP, but with 1.5 (LPA1.5), 8 (LPA8) and 20 (LPA20) mg/kg aspirin respectively, administered 10 min before the first preconditioning I. Results showed that the antiinflammatory dose of aspirin (20 mg/kg) was able to inhibit LP against stunning (C vs LPA20, NS), whereas low (1.5 mg/kg) and intermediate (8 mg/kg) doses did not interfere with the protection (C vs LP, LPA1.5 and LPA8, p<0.01). Moreover, no dose altered the protection against arrhythmias. Conclusion: Antithrombotic aspirin doses would not inhibit LP protection against stunning, whereas high antiinflammatory doses would be potentially deletereous. Since high doses of aspirin blocked LP when administered before the triggering episodes, our results show that the COX pathway might be involved as a trigger of LP against stunning.

Keywords : late preconditioning; aspirin; stunning; arrhythmias; conscious sheep.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License