*= 10 in each group. in groups P, L and P+L. Compared with groups P and L, RPH-2823 IS, serum cTnI and CK-MB levels significantly decreased in group P+L. Compared with group C, serum TNF-, IL-6 and HMGB1 levels, and myocardial expression of p-NF-Bp65 (Ser536) evidently decreased, and myocardial expression of p-GSK-3 (Ser9) obviously increased in groups P, L and P+L. Compared with group P, serum TNF-, IL-6 and HMGB1 levels and myocardial expression of p-NF-Bp65 (Ser536) significantly increased, and myocardial expression of p-GSK-3 (Ser9) evidently decreased in group L. Compared with group L, serum TNF-, IL-6, HMGB1 levels, and myocardial expression of p-NF-Bp65 (Ser536) significantly decreased, and myocardial expression of p-GSK-3 (Ser9) obviously increased in group P+L. In conclusion, our findings indicate that inhibition of GSK-3 to decrease NF-B transcription is usually one of cardioprotective mechanisms of 7nAChR agonist and limb remote ischemic postconditionings by anti-inflammation, but improved cardioprotection by combined two interventions is not completely attributable to an enhanced anti-inflammatory mechanism. for 2 weeks before experiment. They were housed in a Rabbit Polyclonal to ARMX3 silent, heat (24 1C) and humidity (65 10%) controlled room with a 12-h:12-h lightCdark cycle (light beginning at 8 a.m.), and all experiments were performed during the light phase of the cycle. Before experiment, animal was fasted for 12 h, but drunk freely. The rat model of acute myocardial IRI was established, as previously described [11]. After adequate anesthesia with intraperitoneal injection of sodium pentobarbital and tracheal intubation, the rat was ventilated with room air flow using an animal respirator. The ventilation rate was adjusted to 60C80 breaths/min, with the RPH-2823 tidal volume of 2C3 ml/100 g body weight and the inspiratory/expiratory ratio of 1 1:1. The internal jugular vein was cannulated for blood sampling to assay serum concentrations of troponin I (TnI), creatine kinase-MB (CK-MB), and inflammatory cytokines including tumor necrosis factor- (TNF-), interleukin-6 (IL-6), high mobility group protein (HMGB1) and interleukin-10 (IL-10). The carotid artery was cannulated for monitoring heart rate, systolic blood pressure, diastolic blood pressure and mean artery pressure with a MP150 data acquisition and analysis system (Biopac Systems Inc., CA, U.S.A.). The lead II electrocardiogram was constantly recorded by the means of needle RPH-2823 electrodes placed subcutaneously around the limbs. A left thoracotomy was performed via the fourth intercostal space, and the left anterior wall and auricle of the heart were uncovered. After pericardiotomy, a 5-0 silk ligature was placed under the left anterior descending coronary artery (LAD). After an equilibration of 10 min, the ligature was tied for 30 min to block blood flow of LAD and then relaxed for 120 min to resume blood flow of LAD, producing a local myocardial IRI. Experimental protocols By a random number table, 40 rats in whom acute myocardial IRI model had been successfully established were randomly divided equally into four groups subjected to different protocols (10 per group), i.e. control (C), 7nAChR agonist postconditioning (P), limb remote ischemic postconditioning (L) and combined two interventions (P+L) groups. All the rats received the thoracotomy and a 30-min ligature of LAD for ischemia followed RPH-2823 by a 120-min reopening of LAD for reperfusion = 10 in each group. *= 10 in each group. *= 10 in each group. *= 10 in each group. *rat model of 30-min ischemia and 180-min reperfusion is also used and myocardial expression of GSK-3 is usually relatively stable before and after myocardial IRI process. This is probably because there is a stable expression of GSK-3 in myocardium and the interventions used in the present study have no significant effect on myocardial expression of GSK-3. However, this experiment showed that compared with the group C, myocardial expression of p-GSK-3 (Ser9) obviously increased in the groups P, L and P+L. It is in accord with previous findings of Tamareille et als study [15], in which an rat model of myocardial IRI is usually applied, infarct size significantly decreased and myocardial expression of p-GSK-3 (Ser9) evidently increased by limb remote ischemic postconditioning at 20 min of ischemia. These results suggest that inhibition of GSK-3 activity by enhancing phosphorylation of Ser9 site RPH-2823 may be one of cardioprotective mechanisms of limb remote ischemic postconditioning. Moreover, our experiment first confirms that 7nAChR agonist postconditioning can also provide a significant protection against myocardial IRI by this pathway. The available evidence shows that inflammatory hyper-responsiveness is usually a characteristic of IRI, which is basically induced by an endogenous mechanism.