The role of calreticulin in three different kinds of preconditioning against myocardial ischemia/reperfusion injury in rats

Objective To evaluate the role of calreticulin (CRT) in myocardial protection of three different kinds of preconditioning against myocardial ischemia/reperfusion injury. Methods Thirty SD rats were randomly divided into 5 groups:ischemia reperfusion group (IR), ischemia preconditioning group(IP), adenosine preconditioning group (AP), remote preconditioning group(RP), and sham-opera-tion group (blank control). The ischemia/reperfusion model was established in vivo. Hemodynamic chan-ges of heart function were observed,and serum cardiac Troponin T (cTnT), superoxide dismutase (SOD), malondialdehyde (MDA) and the expression of CRT in myocardium were detected. Results ±dp/dt max,serum cTnT and MDA,and the expression of CRT in RP, AP and IP groups were significantly lower than those in IR group, also SOD level in these three groups was higher than in IR group (P<0.05). AP group had a higher SOD level venous IP and RP groups (P<0.05),also cTnT in AP group was lower than in IP and RP groups (P<0.05). Conclusion Remote preconditioning may mimic the protective effect of ischemic preconditioning. Remote preconditioning attenuated myocardial ischemia/reperfusion injury in vi-vo possibly through down-regulating the CRT expression in rats. Key words: Cadiocyte;  Ischemic preconditoning;  Adenosine;  Reperfusion injury;  Calret-iculin