ABSTRACT
Objective To observe the expression of Caspase-12 and GRP78 of endoplasmic reticulum stress (ERS) in cardiac arrest and beating heart mitral valve replacement Methods Thirty patients with rheumatic heart disease mitral stenosis were randomly divided into beating heart group (BH,n=15) and cardiac arrest group(CA, n = 15). Both groups accepted MVR by beating heart surgery and cardiac arrest surgery under cardiopulmonary bypass (CPB) respectively. Right atrial myocardial tissues were collected at prior the start of CPB (T0), after aortic cross-clamping 30 minutes (BH group 30 minutes after CPB, T1) and stitched right atrium (T2) respectively. The method of reverse transcriptase polymerase chain reaction (RT-PCR) was applied to detect the expression level of Caspase-12 and GRP78 in two groups and positive staining of Caspase-12 and GRP78 of myocardial tissue slices in both groups was observed by immunohistochemical method. Results The expression of Caspase-12 in CA group heightened at T1and significantly increased at T2 (P < 0.05) but the expression of Caspase-12 in BH group had increased in T2 only (P < 0.05). Caspase-12 in CA group expressed higher than that in BH group at T1 and T2. The expression of GRP78 had increased at T1 in two groups but it in CA group expressed higher than that inBH group at T2. The number of positive staining of Caspase-12 and GRP78 in CA group was higher than that in BH group at T2. Conclusion MVR of beating heart can reduce the reaction of ERS to enhance the myocardial protection under CPB.