Effect of ischemic post-conditioning on the expression of heat shock protein 70 and serum superoxide dismutase and malondialdehyde at different time phases of myocardial ischemic-reperfusion in rats
Abstract：Objective To explore the effects of ischemic post-conditioning on myocardial infarction size,the expression of heat shock protein 70 (HSP70),serum superoxide dismutase (SOD) and malondialdehyde (MDA) at different time phases of myocardial ischemic-reperfusionon injury in rats.Methods Isogenic adult lewis rat models of cervical heterotopic and working-heart transplantation were established.The recipients were divided into ischemic-reperfusion group,ischemic post-conditioning group and sham operation group.All groups,except sham operation group,underwent cardiac allograft myocardial ischemia obtained by ligating anterior descending (LAD) branch for 30 minutes (min),followed by 3,6,12,24 hours (h) and 2,4,7 days (d) reperfusion respectively.In the ischemic postconditioning group,three cycles of 10 s reperfusion followed by 10 s LAD re-occlusion were applied during the first minute of reperfusion.Myocardial infarction size,the expression of HSP70 and serum SOD activity and MDA content were measured respectively at the end of the reperfusion.Results Compared with those in the sham operation group,the expression of HSP70 and serum MDA content increased(P ＜ 0.01 or P ＜ 0.05),serum SOD activity decreased in both ischemic-reperfusion group and ischemic post-conditioning group at 3,6,12,24 h and 2,4,7 d reperfusion [heat shock protein 70:(7.22 ± 0.98),(9.77 ± 1.98),(10.02 ±2.14),(11.12±2.83),(10.76 ±2.65),(9.23 ±2.01),(8.22±1.12) and (33.38 ±9.12),(36.15 ± 9.67),(40.56±10.34),(50.01 ±13.17),(47.78 ±10.99),(42.21 ±10.58),(35.35 ±8.11) vs (0.91 ± 0.17) ; serum superoxide dismutase:(35 ± 6),(34 ± 4),(31 ± 4),(26 ± 3),(29 ± 4),(35 ± 7),(37 ± 5),(44 ±7),(41 ±6),(40 ±5),(32 ±4),(37 ±5),(44 ±9),(45 ±8) μg/L vs (57 ± 10) μg/L; malondialdehyde:(0.53 ±0.06),(0.57 ±0.06),(0.71 ±0.11),(1.34 ±0.25),(0.77 ±0.11),(0.68 ±0.09),(0.49 ±0.05),(0.47 ±0.05),(0.50 ±0.06),(0.60 ±0.08),(1.08 ±0.19),(0.62 ± 0.11),(0.59 ±0.07),(0.43 ± 0.05) mmol/L vs (0.36 ± 0.04) mmol/L] (P ＜ 0.05).Compared with those in ischemic-reperfusion group,the expression of HSP70 and serum SOD activity increased(P ＜0.01 or P ＜0.05),the serum MDA content and myocardial infarction size decreased in ischemic post-conditioning group [(12.9 ± 2.2),(19.2 ± 7.9),(20.6 ±8.1),(22.7 ±9.0),(21.6 ±8.7),(20.9 ±8.3),(20.8 ±7.5)％ vs (18.4 ±5.3),(30.6 ± 10.2),(34.6±11.2),(38.2±11.4),(38.0±10.6),(37.8±9.3),(35.6±9.1)％](P＜0.05).The peak-time of the expression of HSP70 and serum MDA content and trough-time of serum SOD activity happened at 24 h reperfusion in both ischemic-reperfusion group and ischemic post-conditioning group.Conclusions Ischemic post-conditioning can increase the expression of HSP70 and serum SOD activity,decrease the serum MDA content and myocardial infarction size between 3 h and 7 d after the reperfusion followed by myocardial ischenmia in the rats.However,ischemic post-conditioning can not change the time-to-peak in the expression of HSP70 and serum MDA content and the time-to-trough in the serum SOD activity.
Keywords：Ischemic postconditioningMyocardial ischemia reperfusion injuryHeat shock proteinSuperoxide dismutaseMalondialdehyde
Publication Date：2014-01-01
Online Publishing Date：2026-09-14(First online date of this platform, not the publication date of the document)
Pages：5( 1409-1413 )