Objective: To study the effect of the bolus propofol on myocardial ? adrenergic receptor. Method: Twenty-one,aging 4-6 weeks,male health SD rats,were divided randomly into three groups:low dose group (L)with propofol of 5mg/kg,high dose group(H)with 12mg/kg of propofol and control group(C) with NS alone. The drugs were administered through the rat's tail vein in conscious state. 3 minutes after administration,the raps heart were totally taken out to investigate rat's myocardial ? adrenergic receptors with radioligand binding assay. Result:Compared with those in control group,in L group there was a decrease in ? adrenergic receptor density(Bmax),but no change in the affinity of ? adrenergic receptor (KD); In H group,Bmax decreased,KD value increased. The Bmax and KD were significantly different between L and H group. Conclusion:Intravenous bolus doses of propofol may cause down-regulation on myocardial ? adrenergic receptor of rats in dose-related way.

Objective To evaluate the effect of ultra-low dose naloxone on postoperative hyperalgesia caused by large-dose remifentanil.Methods Forty ASA Ⅰ-Ⅲ adult patients,scheduled for gastrointestinal surgery,were randomly assigned into 2 groups (n =20 each):large dose remifentail group (group R) and ultra-low dose naloxone group (group N).Anesthesia was induced with iv injection of remifentanil,propofol and cisatracurium and maintained with inhalation of sevoflurane and infusion of remifentanil.The patients were tracheal intubated and mechanically ventilated.In group R,remifentanil was infused at a rate of 0.25 μg· kg-1 · min-1 starting from the beginning of skin incision.The infusion rate was adjusted according to hemodynamics during operation and subsequently increased/decreased by 0.05 μg· kg-1· min-1 each time.In group N,naloxone was infused at 0.1 μg·kg-1· h-1 while infusing remifentanil,naloxone infusion was stopped at the beginning of peritoneum closure and the other treatments were similar to those previously described in group R.All patients were sent to post-anesthesia care unit after surgery and stayed there for 90 min.Morphine was given when need.The patient-controlled intravenous analgesia was used for postoperative analgesia after leaving post-anesthesia care unit.The first pain time was calculated.The morphine consumption and complications such as nausea,vomiting and pruritus were recorded at 15,30,60 and 90 min and 2,6,24,48 and 72 h after surgery.Results Compared with group R,the morphine consumption was significantly reduced at each time point after surgery,the first pain time was prolonged,and incidence of nausea was decreased (P ＜ 0.05),while no significant change was found in the incidence of vomiting and prutirus in group N (P ＞ 0.05).Conclusion Infusing ultra-low dose naloxone (0.1μg· kg-1 ·h-1) during operation can attenuate postoperative hyperalgesia caused by large-dose remifentanil in patients.

Objective To investigate the effect of hyperbaric oxygen preconditioning on syngeneic kidney transplantation in rats and to explore the potential mechanism. Methods Forty male SD rats were randomly divid-ed into control group(Sham group),kidney transplantation group(KTx group)and hyperbaric oxygen precondi-tioning group(HBO+KTx group). Kidney transplantation was performed 24 h after hyperbaric preconditioning. Rats were sacrificed 24 h after the transplantation.Serum creatinine(Scr)and blood urea nitrogen(BUN)were de-tected.The level of superoxide dismutase(SOD),malondialdehyde(MDA)and heme oxygenase-1(HO-1)in the graft was examined. Kidney pathological examination was performed after renal tissue fixed. Results Compared with the KTx group,HBO + KTx group showed lower Scr and BUN level. The MDA level was decreased and the SOD activity was increased significantly after hyperbaric oxygen preconditioning in HBO+KTx group.Renal tubu-lar necrosis was significantly reduced in HBO+KTx group.HO-1 level in HBO+KTx group was significantly high-er than that of KTx group. Conclusion Hyperbaric oxygen preconditioning can reduce lipid peroxidation,en-hance antioxidant enzyme activity and improve the level of HO-1 in graft tissue,thus attenuating kidney injury.

Objective To evaluate the efficacy and safety of domestic palonosetron hydrochlo-ride injection on its prevention of postoperative nausea and vomiting.Methods A multi-centered,ran-domized,double-blinded and placebo-controlled clinical trial was carried out.A total of 281 patients were enrolled,with 141 of patients in study group and 140 of patients in control group respectively. 0.075 mg of intravenous palonosetron hydrochloride injection was delivered in the study group before anesthesia induction.The drug was substituted by 1.5 ml of NS in the control group.All anesthesia inductions were conducted by the intravenous injection of propofol,fentanyl and rocuronium,and were maintained with sevoflurane and fentanyl.Complete remission rate and treatment failure cut-off time of vomiting were evaluated at 0-6 h,6-72 h,0-72 h postoperatively.Results In the study group CR% 0-6 h,6-72 h and 0-72 h were 107 (75.89%),104 (73.76%)and 92 (65.25%),the control group was 81 (57.86%),70 (50%)and 62 (42.86%),CR% of the study group was significantly higher than that of the control group (P <0.01).Insignificant statistical difference but significant clin-ical difference exists in their treatment failure cut-off time,386.5 min and 300.0 min,respectively be-tween the groups.Conclusion Domestic palonosetron hydrochloride injection is safe and effective in the prevention of postoperative nausea and vomiting.