Aim To explore the effect of
propofol preconditioning on myocardial ischemia/reperfusion injury and the role of phspho-ERK1/2
during the
propofol preconditioning in
renal hypertension rat(RHR).Methods The isolated RHR hearts perfused on langendorff apparatus were randomly divided into 8 groups(n=8 each).After 20 min of perfusion for equilibration,the CTRL group was subsequently perfused by 148 min.The ISCH group was submitted to 35 min of ischemia and 60 min of reperfusion(I/R) to induce ischemia/reperfusion injury.The DMSO group was given by once 18 min and twice 10 min K-H solution containing 20 μmol·L~(-1) DMSO and 5 min K-H solution reperfusion prior to I/R procedure.The three propofol preconditioning groups were preconditioned by giving 2 cycles of 10 min K-H solution containing 30 μmol·L~(-1),100 μmol·L~(-1) or 300 μmol·L~(-1) propofol and 5 min K-H solution reperfusion prior to the I/R procedure.The PD group and the PD+P100 group were given K-H solution containing 20 μmol·L~(-1) PD98059,an ERK1/2 kinase specific inhibitor,for 18 min and 5 min K-H solution washout before I/R and 100 μmol·L~(-1) PPC respectively.Cardiac functional indices were recorded.Activity of SOD and content of MDA were measured.The level of phspho-ERK1/2 protein expression was measured using Western Blotting.Results Compared with those in the CTRL group,the recovery of cardiac functional indices in ISCH group became worse(P<0.01).Those in P100 group significantly improved compared to those in ISCH group(P<0.01),and pretreatment of 20 μmol·L~(-1) PD98059 abolished its protective effect.The myocardial content of MDA in P100 group was less than those in CTRL group and in PD+P100 group,but the myocardial activity of SOD in P100 group was higher than those in CTRL group and in PD+P100 group.The level of cytosolic and nuclear phspho-ERK1/2 protein expression in P100 group was higher than those in ISCH group and in PD+P100 group.Conclusion 100 μmol·L~(-1) propofol preconditioning reduced cardiac ischemia/reperfusion injury in isolated renal hypertension rat.The increase of myocardial phspho-ERK1/2,especially the nuclear one,may be involved in this effect.