Objective To investigate the protective effect and the mechanism of isoflurane preconditioning on rat brain tissue suffering from rat liver ischemia-reperfusion injury .Methods 75 SD rats were randomly divided into five groups, sham group (S group);ischemia-reperfusion group (I/R group): liver ischemia for 60 min, reperfusion for 120 min;isoflurane preconditioning group ( ISO group ): 60 min before liver I/R, ISO pretreatment for 30 min; CsA +ISO group;CsA ( MPTP specific blocker ) 50 mg/kg intravenous injection , the same as ISO group after 30 min; CsA group:CsA 50 mg/kg intravenous injection .30 min before I/R.The animals were killed 24 h after ischemia and their brain were excised for measurement of mitochondrial permeability transition pore ( MPTP) and calcium content in mitochondria .The measurement of content of S-100βprotein in serum before ischemia and 120min after reperfusion through the application of Elisa kit.Results The mitochondrial Ca2+concentration of I/R group(287.32 ±26.17)was higher than that in S group (198.54 ±21.02) and the ISO group (209.74 ±29.49) ( P <0.05), and Ca2 + concentration of CsA +ISO group (267.31 ±37.52) was higher than the ISO group (P <0.05);there was not statistical significance between I/R and CsA group(288.63 ±23.15)(P <0.05).MPTP were more opened in I/R group(△S:1.73 ±0.24)than that in S group (△S:2.36 ±0.35)and ISO group(△S:2.11 ±0.32)(P <0.05),but MPTP were more opened in CsA +ISO group than that in ISO group (P <0.05).The content of S-100βprotein in serum was significantly higher in I/R group than that in sham and ISO groups (P <0.05),and the content of S-100βprotein in serum was significantly higher in CsA +ISO group than in the ISO groups ( P <0.05 ) .Conclusion The liver ischemia-reperfusion may injury the brain of the rat and isoflurane preconditioning can protect the brain on the rat .The reduce of mitochondria calcium overload and inhibition of MPTP opening are involved in the mechanism .

Objective To observe different priming techniques with intubation dose when using cisatracurium in onset time and safety. Methods Eighty ASA physical status Ⅰ and Ⅱ patients undergoing elective surgery requiring general anesthesia were enrolled. Group Ⅰ with 20 cases received cisatracurium 0.010 mg/kg, group Ⅱ with 20 cases received cisatracurium 0.015 mg/kg,group Ⅲ with 20 cases received cisatracurium 0.010 mg/kg,and group Ⅳ with 20 cases received normal saline. Four minutes after priming,group Ⅰ received cisatracurium 0.140 mg/kg ,group Ⅱ received cisatracurium 0.135 mg/kg, group Ⅲ received cisatracurium 0.190 mg/kg,and group Ⅳ received cisatracurium 0.200 mg/kg. Mechanomyography assessed the neuromuscular function of the adductor pollicis with train-of-four (TOF) supramaximal impulses T1. The trachea was intubated when the amplitude of T1 decreased to 0. Recorded T1 and TOF in 4 minutes and onset time of muscle relaxation, then evaluated intubation condition. Results The onset time in group Ⅰ , Ⅱ, Ⅲ and Ⅳ were (151.30 ± 10.90), (138.90 ±8.37), (145.45 ± 17.12), (148.75 ± 18.70) s,respectively. The onset time in group Ⅱ was obviously shorter than that in group Ⅰ , Ⅲ and Ⅳ (P ＜ 0.01 ),thus there was no significant differences among the group Ⅰ , Ⅲ and Ⅳ. During the priming interval, the value of T1 and TOF were both showing downtrend, in group Ⅱ ,there was TOF ＜ 90%. Conclusions Priming dose 0.010 mg/kg and intubation dose 0.140 mg/kg is just the same like that in intubation dose of quadruple ED95 whether priming. There is no benefit in priming cisatracurium of intubation dose quadruple ED95. There is TOF ＜ 90% in 4 minutes priming interval when using priming dose 30% ED95 and it is proved unsafely.

OBJECTIVETo explore effects and potential mechanisms of high insulin environment on high density lipoprotein (HDL) generation-related functional protein ABCA1.

METHODS[(3)H] labeled cholesterol efflux from mature 3T3-L1 adipocytes was detected by liquid scintillation counting. ABCA1 mRNA and protein expression in mature 3T3-L1 adipocytes post stimulation with various concentrations of insulin was detected by real-time fluorescence-based quantitative techniques and Western blot, respectively, in the absence and presence of CHX (cycloheximide, CHX), calpeptin (calpain pathway inhibitor) or MG-132 (proteasome pathway inhibitor).

RESULTSCholesterol efflux rates were reduced post insulin stimulation in a dose-dependent manner ((7.06 ± 0.27)%, (6.59 ± 0.30)%, (6.34 ± 0.24)%, (5.07 ± 0.40)%, and (4.71 ± 0.40)% at 0, 1, 10, 10², and 10³ nmol/L of insulin, P < 0.05). Cholesterol efflux rates decreased in a time-dependent manner post 10³ nmol/L insulin stimulation (6.52 ± 0.30)%, (5.59 ± 0.71)%, (5.44 ± 0.37)%, (4.52 ± 0.32)%, and (4.38 ± 0.33)% at 0, 2, 4, 6, 12 h, respectively). ABCA1mRNA levels were not affected by insulin (P > 0.05). ABCA1 protein level was significantly downregulated in 10³ nmol/L insulin group compared to 0 nmol/L insulin group (P < 0.01). Compared with the 0 h group, ABCA1 protein level was significantly reduced in 6 h group (P < 0.05) and further reduced in 12 h group (P < 0.01). Both calpeptin and MG-132 could partly reduce insulin-induced degradation of ABCA1. Compared with the negative control group, ABCA1 protein levels were significantly upregulated by cotreatment with calpeptin and MG-132, respectively (both P < 0.01).

CONCLUSIONOur data suggest that high insulin level could promote the ABCA1 protein degradation and reduce cholesterol efflux from mature 3T3-L1 adipocytes through calpain and proteasome pathway, thus, produce a circumference not suitable for nascent HDL formation in 3T3-L1 adipocytes.

3T3-L1 Cells ; ATP Binding Cassette Transporter 1 ; Adipocytes ; Animals ; Calpain ; Insulin ; Leupeptins ; Lipoproteins, HDL ; Mice ; Proteasome Endopeptidase Complex ; RNA, Messenger