Objective To investigate the effect of pretreatment with dexmedetomidine alone or in combination with sufentanil on myocardial ischemia-reperfusion (I/R) injury in rats.Methods Fifty healthy male Sprague-Dawley rats,weighing 250-300 g,were anesthetized with intraperitoneal pentobarbital sodium 60 mg/kg.Myocardial I/R was induced by occlusion of anterior descending branch of left coronary artery for 30 min followed by 120 min of reperfusion.The rats were then randomly divided into 5 groups (n =10 each):sham operation group (group S),group I/R,dexmedetomidine pretreatment group (group DP),sufentanil pretreatment group (group SP),and dexmedetomidine + sufentanil pretreatment group (group DS).In group S the anterior descending branch was only exposed but not ligated.Dexmedetomidine 0.5μg/kg and sufentanil 0.1μg/kg were injected intraperitoneally 30 min before ischemia in groups DP and SP,respectively.Dexmedetomidine 0.5 μg/kg and sufentanil 0.1 μg/kg were injected intraperitoneally 30 min bbefore ischemia in group DS.Arterial blood samples were collected at 120 min of reperfusion for determination of serum creatine kinase (CK) and lactic dehydrogenase (LDH)concentrations.The rats were sacrificed at 120 min of reperfusion and hearts were removed for microscopic examination.Myocardial infarct size was calculated.The malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in myocardial tissues were measured.Results Compared with group S,the serum CK and LDH concentrations were significantly increased,the myocardial infarct size was enlarged,and SOD activity was decreased in the other groups,MDA content was significantly increased in groups I/R,DP and SP (P ＜ 0.05 or 0.01).Compared with group I/R,the serum CK and LDH concentrations,MDA content and myocardial infarct size were significantly decreased,and SOD activity was increased in groups DP,SP and DS (P ＜ 0.05).Compared with group DS,the serum CK concentration was significantly increased,the myocardial infarct size was enlarged,and MDA content was increased in groups DP and SP,and LDH concentration was significantly increased and SOD activity was decreased in group DP (P ＜ 0.05).The pathological changes were significantly attenuated in groups DP and SP compared with group DS.Conclusion Dexmedetomidine pretreatment can reduce myocardial I/ R injury in rats,dexmedetomidine combined with sufentanil pretreatment provides better efficacy than either alone,and inhibition of lipid peroxidation is involved in the mechanism.

Objective To evaluate the effect of ulinastatin on oxidative stress injury to myocardial cells in diabetic rats in vitro.Methods The H9c2 cells were cultured in DMEM culture medium and the cells at the logarithmic growth phase were seeded in 96-well plates (density 1 × 104 cells/ml,200 μl/well) or in 6-well plates (density 1× 105 cells/m1,2 ml/well).The cells were randomly divided into 4 groups (n=18 each) using a random number table:normal control group (group C),high-glucose group (group HG),high-glucose + oxidative stress group (group HG+OS),ulinastatin +high-glucose+oxidative stress group (group U+HG+OS).The cells were cultured in high-glucose DMEM culture medium (25.0 mmol/L) for 48 h in group HG.After the cells were cultured in high-glucose DMEM culture medium for 24 h,H2O2 with the final concentration of 500 μmol/L was added to the high-glucose culture medium,and the cells were continuously cultured for 24 h in HG+OS and U+HG+OS groups.In group U+HG+OS,ulinastatin 400 U/ml was added to the high-glucose culture medium.The cells were collected for determination of cell viability,H9c2 apoptosis,activity of superoxide dismutase (SOD) and contents of malonadehyde (MDA).Apoptosis rate was calculated.The cell culture supernatant was collected for detection of lactate dehydrogenase (LDH) activity.Results Compared with group C,the cell viability and SOD activity were significantly decreased,and the apoptosis rate,MDA content and LDH activity were increased in the other groups.Compared with HG group,the cell viability and SOD activity were significantly decreased,and the apoptosis rate,MDA content and LDH activity were increased in HG+OS and U+HG+OS groups.Compared with group HG+OS,the cell viability and SOD activity were significantly increased,and the apoptosis rate,MDA content and LDH activity were decreased in group U + HG+ OS.Conclusion Ulinastatin can mitigate oxidative stress injury to myocardial cells in diabetic rats,and inhibited cell apoptosis is involved in the mechanism.

Objective To compare the effectiveness and feasibility of oral tracheal intubation with Clarus video stylet,HPHJ-A video laryngoscope and Airtraq laryngoscope and in snoring pa-tients.Methods Ninety patients undergoing elective snoring surgery with general anesthesia,3 9 males and 51 females,aged 22-55 years,BMI 25-29 kg/m2,ASA physical status Ⅰ-Ⅲ,were ran-domly divided into three equal-sized groups (n=30):Clarus Video Stylet group (group C),HPHJ-A video laryngoscope group (group H)and Airtraq laryngoscope group (group A).The time of success-ful endotracheal intubation and the success rate of initial intubation of all groups were observed.The mean arterial pressure (MAP),heart rate(HR)and Rate-pressure product(RPP)were also monitored before induction of anesthesia(T0),before tracheal intubation(T1),at 0 min(T2),1 min (T3),and 3 min (T4)after intubation,as well as the throat injury and hemorrhage were noted. Results Patients in group C were successful intubated.Two patients in group H and one patient in group A with failed intubation were successfully intubated by using Clarus video stylet.The time re-quired for successful intubation in group C was longer than groups H and A (P<0.05).Compared with T0,the increasing of hemodynamic parameters (MAP,HR,RPP)after induction of all groups were significant(P<0.05).Compared with T1,the HR,MAP and RPP were increased significantly at T2in all groups (P<0.05).Compared with T1,the MAP and RPP were increased significantly at T3in all groups,and the HR were increased significantly at T3in groups H and A (P<0.05).There was no significant difference in the HR between T1and T3in group C.The increase in the HR and RPP at T2 was lower in group C than that in both the groups H and A (P <0.05).The changes of hemodynamic parameters were no significant among the three groups at other time.The differences of sore throat score and hemorrhage were no significant.Conclusion Compared with HPHJ-A video laryngoscope and Airtraq laryngoscope,Clarus video stylet for guiding oral tracheal intubation in snoring patients have less influence on hemodynamic parameters,and have no limited mouth opening. But Clarus Video Stylet spends longer intubating times,and has no obvious advantages on preventing throat injury.