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.

Male Sprague~Dawley rats were pretreated with phenobarbital and randomly divided into 6 groups and were exposed to O2,/N2/l. 2 MAC anesthetics for I hr; NC, 21 % O2/79% N2; HC, 14 %O2,/86%N2; NH, 21 %O2/79% N2/l. 2 MAC halothane;HH, 14 %O2/86 %N2/ 1. 2 MAC Halothane; NS, 21 %O2/79%N2/ 1. 2 MAC sevoflurane; HS, 14 %O2/86 %N2/ 1. 2 MAC sevoflurnae. Liver specimens andblood were taken 24 hrs after exposure. Thenecrosls and denaturatlon of hepatocellularwere quantltatlvely estlmated by stereoscopy.Ultrastructural morphology was analysed by computer. The liver ofall rats given halothane (14%O2) had extensive centrilobu- lar necrosls and denaltlration. There were an increase in serum glutamic pyruvic transmi- nase accompnaying the morphologic damage。No marked hepatotoxicity was foundin the rats following sevoflurane expoure compared with controls. Hypoxia was the main cause of swelling of mltochondria. Results suggest that sevoflurane has less hepattc injtry than holotnane.

500?mol/L) of propofol was needed; In biological system near the range of anaesthetic concentration, propofol effectively scavenged oxygen free radical produced by respiratory burst of PMN. Conclusion: Propofol scavenging hydroxyl radical generated in biological and nonbiological system,may be one of the main mechanisms of its antioxidation,the intralipid component of Diprivan may affect its antioxidation.

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.

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.

Objective To examine the analgesic effect of intrathecal (i.t.) adenovirus containing human beta-endorphin (?-EP) gene in a rat model of neuropathic pain produced by chronic constrictive injury (CCI) . Methods Thirty-six male SD rats weighing 210-260 g were randomly divided into 3 groups: (1) blank control group (n = 5); (2) sham-operated group (n = 5) ; (3) neuropathic pain group (n = 26) . The neuropathic pain group was further divided into 3 subgroups: Ad-NEP subgrouop (n = 9); Ad-GFP (the recombinant adenovirus containing green fluorescent protein) subgroup (n = 9) and normal saline (NS) subgroup (n = 8). The animals were anesthetized with intraperitoneal ketamine 100 mg?kg-1 and atropine 50 mg?kg-1. Neuropathic pain was produced by ligation of right sciatic nerve according to the technique described by Bennet and Xie. In sham-operated group the sciatic nerve was exposed but not ligated. In blank control group no operation was performed. Seven days after the surgery a PE-10 catheter was placed in the subarachnoid space at L5,6 according to the method of Milligan et al. Seven days after catheter placement 1?108 pfu Ad-NEP, Ad-GFP and 0.9% saline were injected i.t. via the catheter respectively. The paw-withdrawal latency to radiant heat was measured before surgery (T0,baseline) , the day of i.t. injection (T1) and 1 day (T2) , 1 w (T3), 2 w (T4), 3 w (T5), 4 w (T6) 5 w (T7) after i.t. injection. At one week after i.t. administration one animal in Ad-NEP subgroup and Ad-GFP subgroup was killed and the lumbar segment (L3-6) of the spinal cord was removed for immuno-histochemical examination. Naloxone 1 mg?kg-1 was given intraperitoneally in Ad-NEP subgroup (n = 8) and Ad-GFP subgroup (n = 8) at 10 days after i.t. injection. Pain threshold to thermal stimulation of the right paw was measured before (t0) and from 10-90 min after intraperitoneal naloxone injection at an interval of 10 min (t1-9). CSF samples were obtained at T1-7 for determination of CSF concentration of ?-EP using radio-immunological assay. Results The right paw-withdrawal latencies (PWLs) were significantly lower in Ad-GFP subgroup and NS subgroup than in blank control and sham-operated groups (P

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