ObjectiveIn order to improve the survival of graft liver after liver transplantation, this study was designed to investigate whether intraportal injection of 150mg/kg N-acetylcysteine (NAC) in rats could reduce hepatic ischemia-reperfusion injury after 48 h of cold storage and 2 h of reperfusion. Methods Healthy male Wistar rats weighing 250-350g were used. The study consisted of three groups: control group (group Ⅰ) ;NAC-treated group(group Ⅱ). 1 ml of 5% dextrose (D5%) or 1 ml D5% containing 150mg/ kg NAC was injected into the superior mesenteric vein. 15 min after the injection of D5 % or NAC the liver was flushed with cold (4℃) Ringer' s solution through the portal vein . After perfusion, the liver was removed and kept in 100 ml UW solution at 4℃ for 48 h. In group Ⅲ animals were pretreated with buthionine sulfoximine (BSO) 2 h before intraportal injection of D5 % or NAC and liver harvesting. After cold storage, the livers were then perfused for 2 h by a closed circulating system. Aspartate transaminase (AST), alanine transaminase (ALT), and lactate dehydrogenase (LDH) activities in the perfusate were determined by reflectometry. Lactate and acid phosphatase activities were determined by enzymatic methods. ResultsAfter 48 h of cold storage and 2 h of reperfusion, livers from NAC-treated group produced larger amounts of bile than those in the control group, and released less LDH, AST, ALT and acid phosphatase, a marker of Kupffer cell injury in the perfusate. The protective effects of NAC against cold ischemia-reperfusion liver injury were maintained when animals were pretreated with BSO, a specific inhibitor of glutathione synthesis. ConclusionsThis study shows that intraportal administration of NAC in vivo significantly improves the initial function of the isolated rat liver. Our results also indicate that NAC inhibits the activation of Kupffer cells, which are the first source of reactive oxygen intermediates during reperfusion.

Rat liver mitochondria were exposed to various conentrations of halothane,enflurane, isoflurane and sevoflurane. Electron transfer rates from NADH and succinate to cytochrome C were measured by scanning dual wavelength spectrophotometer. Statistical analysis of the data suggested that halothane at clinical or higher than clinical concentrations markedly inhibited activities of NADH-Cyt,C reductase.in contrast,no decrease occurred in the activities of NADH dehydrogenase,NADH-coenzyme Q reductase and enzymatical system of succinate chain. Enflurane,isoflurane and sevoflurane had little effect on enzymatical system of mitochondrial electron transfer chain. These data indicate that halothane interfere with utilization of NADH-linked substrate by blocking electon transport from NADH to cytochrome C and it is probable that the locus of action is at Q binding protein(Qpn) or complex of Qpn and ubiquinone.

Objective In order to improve the survival of graft liver after liver transplantation, this study was designed to investigate whether intraportal injection of 150mg/kg N-acetylcysteine (NAC) in rats could reduce hepatic ischemia-reperfusion injury after 48 h of cold storage and 2 h of reperfusion.Methods Healthy male Wistar rats weighing 250-350g were used.The study consisted of three groups: control group (group Ⅰ);NAC-treated group(group Ⅱ).1 ml of 5% dextrose (D5%) or 1 ml D5% containing 150mg/kg NAC was injected into the superior mesenteric vein.15 min after the injection of D5% or NAC the liver was flushed with cold (4℃) Ringer's solution through the portal vein .After perfusion, the liver was removed and kept in 100 ml UW solution at 4℃ for 48 h.In group Ⅲ animals were pretreated with buthionine sulfoximine (BSO) 2 h before intraportal injection of D5% or NAC and liver harvesting.After cold storage, the livers were then perfused for 2 h by a closed circulating system.Aspartate transaminase (AST), alanine transaminase (ALT), and lactate dehydrogenase (LDH) activities in the perfusate were determined by reflectometry.Lactate and acid phosphatase activities were determined by enzymatic methods.Results After 48 h of cold storage and 2 h of reperfusion, livers from NAC-treated group produced larger amounts of bile than those in the control group, and released less LDH, AST, ALT and acid phosphatase, a marker of Kupffer cell injury in the perfusate.The protective effects of NAC against cold ischemia-reperfusion liver injury were maintained when animals were pretreated with BSO, a specific inhibitor of glutathione synthesis.Conclusions This study shows that intraportal administration of NAC in vivo significantly improves the initial function of the isolated rat liver.Our results also indicate that NAC inhibits the activation of Kupffer cells, which are the first source of reactive oxygen intermediates during reperfusion.

Objectives To find out the effects of estrogen and clomiphene on behavior of epileptic rats induced by kainic acid (KA) and probe into some mechanisms. Methods Ovariectomized Sprague-Dawley female rats were treated with estrogen (E) or estrogen and clomiphene (C). Their behaviors when they were induced seizures were observed and compared. Indirect immunofluorescence method was used to measure the alterations of gamma-aminobutyric acid (GABA) immunoreactive cells and ?1 subunits of GABA_A receptors in the hippocampus of all groups. Results The latency and time at reaching 4/5 degrees in KA+E group ((24.63?11.44) minutes and (41.50?16.22) minutes, respectively) were reduced greatly than KA group ((46.75?14.61) minutes and (65.13?12.99) minutes), while the latency of (KA+)E+C group (adding estrogen and clomiphene, (43.50?5.75) minutes) became prolonged significantly than in KA+E group. Conclusion High-level estrogen should be proconvulsant and the clomiphene might have some antiepileptic effects, which may be related with some alterations of GABA energic function in the brain.

The essence of training for clinical postgraduates is comprehensive capacity,including clinical and scientific research capacity,and the demand for the former is relatively higher than the latter. By means of discussion on the source and the educational system for postgraduates,we try to train clinical anesthesiology postgraduates with high diathesis and meet the needs of clinical anesthesia.

Clinical practice is an important teaching stage for interns of anesthesiology in medical universities.We discuss advantages and disadvantages for different teaching modes in the course of clinical practice,aiming at choosing a better one to optimize practice quality and bringing up graduates with high diathesis.

Objective To observe how the ACC transmits nociceptive information and how it regulates spinal noceciption.Methods A total of 32 male SD rats were randomly divided into four groups:Sham group,CCI group,ACC group,and AP-5 group.After light-dark transition test, forced swimming test (FST),paw withdrawal mechanical threshold (PWMT),paw withdrawal ther-mal latency (PWTL)had been measured,the rats were finally anesthetized,then ACC and the spinal cord was rapidly removed,the expression of cAMP-response element binding protein (pCREB)and extracellular regulated protein kinases (pERK)were measured by Western blot.Results Compared with the sham group,the PWMT of the CCI rats were significantly decreased,rats spent less time in the light compartment and number of transition were decreased (P <0.01 ).The immobility time in FST were also significantly prolonged (P <0.01).After AP-5 injected in bilateral ACC 13 days after CCI operation,the PWMT of the CCI rats were significantly increased,rats spent more time in the light compartment and number of transition were increased (P <0.01).The immobility time in FST were also significantly shortened (P <0.01).Compared with sham group,the expression of pCREB, pERK increased significantly in ACC in CCI group (P <0.01).The expression of pCREB,pERK in spinal cord was increased in CCI group and decreased in AP-5 group (P <0.01 ).Conclusion ACC facilitate the spinal nociception in a descending mode.

Objective To establish a method for acute isolation of rat superior cervical ganglion (SCG) cells and identify the electrophysiological properties.Methods Sprague-Dawley rats of both sexes,aged 5-12 days,were decapitated.The SCGs were removed quickly,and the single SCG cell was enzymatically isolated from the SCGs.When the holding potential was - 60 mV,100 μmol/L acetylcholine was applied and the nicotinic acetylcholine receptor currents were recorded by whole-cell patch-clamp technique.When the holding potential was 760 mV,65 mmol/L KCl was applied and quantal release of catecholamines was detected by using carbon fiber electrodes.Results SCG cells with normal electrophysiological properties were isolated.Typical nicotinic acetylcholine receptor currents and quantal release of catecholamines were recorded successfully.Conclusion The cells suitable for patch-clamp experiments can be obtained by using the method for acute isolation of rat SCG cells.

Objective To investigate the effect of different concentrations of heparin in the cold preservation solution on blood coagulation after reperfusion during orthotopic liver transplantation ( OLT) . Methods Forty ASA Ⅱ or Ⅲ patients with end-stage liver disease (31 males, 9 females) weighing 51-82 kg undergoing OLT were randomly divided into 3 groups according to the concentrations of heparin in the liver preservation solution: group Ⅰ 2 000 U?L-1( n = 14); group Ⅱ 8000 U?L-1(n= 12) and group Ⅲ 20 000 U?L-1(n = 12) .Anesthesia was induced with propofol, fentanyl and rocuronium and maintained with isoflurane inhalation and intermittent i.v. boluses of fentanyl. Body temperature was maintained at 35.5-37.5℃ and Hct at 22%-35% . Blood samples were taken from central vein at 15 min before reperfusion (T0,baseline) and 5, 30, 60, 120 and 180 min of reperfusion (T1-5) for determination of ACT, CR and platelet function (PF) using Sonoclot platelet function and coagulation analyzer (U.S.A.). Blood concentration of heparin was determined in 3-4 patients in each group at T0-5 ( HPLC) . Results The 3 groups were comparable with respect to age, body weight, ASA physical status and Child classification. The glass ball activated coagulation time (gbACT) was significantly prolonged at T1-4 in group Ⅲ and at T1,2 in group Ⅱ as compared to the baseline values at T0 ( P