Role of stress in myocardial protection of ischemic preconditioning / 中南大学学报(医学版)

ABSTRACT

Objective:To determine the role of stress in myocardial protection of ischemic preconditioning (IPC). Methods:hTirty rabbits were randomly divided into an IPC group, an etomidate (Etom) group, an ischemic/reperfusion (IR) group, a methylprednisolone (MP) group and a sham group. hTe ratio of infarction size versus risk area (infarct/risk) was calculated. hTe elevations of the serum creatine kinase (CK) activity and cardiac troponin I (cTnI) concentrations as well as the serum cortisol concentrations were measured. Results:hTe percentages of infarct/risk in the IPC group, the MP group, the IR group, and the Etom group were (5.86±2.81)%, (11.28±3.62)%, (26.79±4.53)%, and (18.19±3.72)%, respectively. The elevations of the serum CK activity in the IPC group, the MP group, the IR group, and the Etom group were (255±89), (314±160), (855±371), and (768±404) U/L, respectively. hTe elevations of serum cTnI concentrations in the IPC group, the MP group, the IR group, and the Etom group were (3.6±0.6),(6.1±2.2), (8.1±3.6), and (6.4±1.6)μg/L, respectively. Those indicators among the groups were signiifcantly different (P Conclusion: A blunted cortisol reaction can markedly reduce the benefit of IPC while methylprednisolone shows cardioprotective effects, suggesting that stress might be involved in the myocardial protection of IPC.