Damage to Hippocampus of Rats after Being Exposed to Infrasound

Objective The objective was to observe damage of hippocampus in rats after exposure to infrasound, and to assess HSP70 expression in hippocampus.
Methods SD rats in the experimental group were exposed to 140 dB (8 Hz) infrasound for 2 h per day for 3 days. The morphology of the hippocampus was examined by transmission electronic microscopic (TEM). Cell apoptosis was observed by TUNEL staining at 0 h, 24 h, 48 h, and 2 w after exposure. HSP70 expression was detected by immunohistochemistry (IHC) and Western blotting (WB).
Results TEM showed that hippocampus was significantly damaged by exposure, and exhibited recovery 1 week after exposure. The TUNEL data showed that neuronal apoptosis after exposure was significantly higher than in the control rats at 24 h and 48 h, and the apoptotic cells decreased one week after exposure. IHC and WB showed HSP70 expression was significantly higher in the exposed rats, peaked at 24 h.
Conclusion Exposure to 140 dB (8 Hz) infrasound for 2 h per day for 3 days appeared to induce damage to the hippocampus of rats, based on changes in ultrastructure and increased cell apoptosis. However, recovery from the damage occurred overtime. HSP70 expression also increased after the exposure and decreased by 48 h.     

针灸脑缺血再灌注损伤大鼠百会及足三里穴位对热休克蛋白70及肿瘤坏死因子-α表达的作用

Objective:To explore the effects of acupuncture on the peripheral serum expression of heat shock protein 70(HSP70)and tumor necrosis factor a(TNF-α)in rats with cerebral ischemia-reperfusion injury(CIRI).Methods:In total,152 Sprague-Dawley(SD)rats were randomly divided into an operated group and a non-operated group according to a random digits table.The operated group included a sham-operated group,a model group and an acupuncture group,whereas the non-operated group consisted of a normal group.Except for the normal group,each group was further divided into 12,24,48,72,96,and 144 h time points according to different reperfusion times.Eight rats were assigned in each operated group and in the normal group.The rat model of CIRI was established by the thread occlusion method in the model and acupuncture groups.The acupuncture group was treated with electroacupuncture at Baihui(DU20)and Zusanli(ST36)for the required time after successful operation.Blood was sampled to detect the HSP70 and TNF-αcontent by enzyme linked immunosorbent assay.Results:The expression of HSP70 protein in the peripheral serum of the experimental groups was higher than that in the normal control group.The peak time in both the model and the sham-operated groups was 12 h,and the peak time in the acupuncture group was 24 h.The expression in the acupuncture group declined to a lower level at 72 h and was lower than that in the model and sham-operated groups(P0.05).The peak time for the expression of TNF-αprotein in the peripheral serum of both the model and the acupuncture groups was 24 h,but the expression in the acupuncture group was lower than the model group.Additionally,the expression of TNF-αin all experimental groups was higher than the normal group(P0.05).Conclusions:Acupuncture at DU20 and ST36 in rats attenuated CIRI,which was associated with a reduction in the expression of HSP70 and TNF-α.These results provide clues to acupunctural neuroprotective properties.Acupuncture at DU20 and ST36 in rats after CIRI can adjust the expression of HSP70 and TNF-αin the peripheral serum,which might be one of the mechanisms of acupuncture's attenuation of CIRI.     

生长抑素对成人活体肝移植围术期肝功能的影响及其可能机制的研究

Background The aim of this study was to investigate the possible effect of somatostatin on the liver function of recipients undergoing living donor liver transplantation.Methods Forty recipients were randomized into group A （n=20） and group B （n=20）. Recipients in group A received no somatostatin whereas somatostatin was administrated for recipients in group B perioperatively. Liver function, the plasma concentration of endothelin-1 and nitric oxide, the intragraft expressions of endothelin-1 and inducible nitric oxide syntheses at 2 hours after declamping of the portal vein were compared between the two groups.Results Compared to group A, alanine transaminase values in group B were significantly reduced at 2 hours after portal vein declamping, at the end of the operation and postoperation day 1 （P 〈0.05）, whereas aspartate aminotransferase values in group B decreased at 30 minutes after portal vein clamping, at 2 hours after portal vein declamping and at the end of the operation （P 〈0.05）. Total bilirubin values in group B were reduced significantly at 2 hours after portal vein declamping and at the end of the operation when compared to group A （P 〈0.05）. Intragraft expression of endothelin-1 was significantly downregulated at 2 hours after declamping of the portal vein accompanied with a reduction of plasma concentration of endothelin-1 in the peripheral blood （P 〈0.05）.Conclusions Somatostatin had a protective effect on liver function during the early phase after declamping of portal vein for recipients undergoing living donor liver transplantation, and the possible mechanism might be partially attributed to the downregulation of endothelin-1.     

Inhibitory effects of selenium on telomerase activity and hTERT expression in cadmium-transformed 16HBE cells

Objective To investigate the effects of sodium selenite on telomerase activity and expression of hTERT mRNA in cadmium-transformed 16HBE cells.Methods Telomerase activity and expression of genes were measured after cultured cadmium-transformed 16HBE cells were exposed to sodium selenite at different doses(0.625,1.25,2.50,5.00 μmol/L)for 24 hours.Results Selenium decreased telomerase activity in cadmium-transformed 16HBE cells.There existed an obvious dose-effect relationship between the selenium concentration and these changes.The expression of hTERT and c-myc mRNA also decreased but the expression of mad1 mRNA increased after exposure to selenium for 24 hours.No difference was found in expression of hTRF1 and hTRF2 mRNA after incubated with sodium selenite for 24 hours,compared with control group.Conclusion Selenium inhibits telomerase activity by decreasing hTERT and c-myc mRNA expression and increasing mad1 mRNA expression in cadmium-transformed 16HBE cells and selenium concentration is significantly correlated with these changes.     

The role of angiopoietin-1 and thrombospondin-1 in the kidney of rats subject to 5/6 nephrectomy

The expression of angiopoietin- 1 （Ang- 1） and thrombospondin- 1 （TSP- 1） in 5/6 subtotal nephrectomy （STN） rats model, and its correlation to the renal microvasculature injury were investigated. Rat 5/6 STN model was established in adult male SD rats, and the sham-operated group and 5/6 STN group were set up. The renal function and histopathological changes were examined at the 1st, 2nd, 4th, 8th and 12th week after operation. The expression orAng-1, TSP-1 and CD31 in renal tissues was detected by using immunohistochemistry. From 2nd to 8th week after operation, Ang-1 was significantly expressed in glomeruli of rats with STN. Ang-1 staining in glomeruli of STN group was increased significantly as compared with that in sham-operated group at 4th and 8th week after operation, and subsequently decreased after the 12th week. The expression of TSP-1 was increased significantly in STN group. As compared with sham-operated group, the CD31 expression was significantly down-regulated from the 2nd week. The expression of Ang-1 mRNA was detected by using RT-PCR at the same time points. The expression of Ang-1 mRNA in renal tissue of rats with STN was significantly up-regulated at the 2nd, 4th and 8th week after operation as compared with that in STN group at other time points or in sham-operated group at the same time points, while decreased evidently at the 12th week as compared with that in sham-operated group. It is concluded that there are changes in the mRNA expression of Ang-1, and the significant up-regulation of the expression of TSP-1 in renal tissue of rats with STN, which may be involved in the remnant renal microvasculature injury.     

CONSTRUCTING ADENO-ASSOCIATED VIRUS-TGFβ3 AND COMPARING ITS BIOLOGICAL EFFECT ON PROTEOGLYCAN SYNTHESIS IN DEDIFFERENTIATED NUCLEUS PULPOUS CELLS WITH ADENOVIRUS-TGFβ1

Objective To construct adeno-associated virus (AAV) expression system for transforming growth factor β3 (TGFβ3) and detect its biological effect on proteoglycan synthesis of the earlier and later dedifferentiated rabbit lumbar disc nucleus pulpous (NP) cells, which was compared with that of adenovirus (AV) expression system for TGFβ1. Methods TGFβ3 gene was obtained using PCR. Its upstream contained restriction enzyme site Kpn Ⅰ, and its downstream contained restriction enzyme site SalⅠ. Using the restriction enzyme sites of PCR product of TGFβ3 and the corresponding multiple cloning site (MCS) in plasmid AAV, TGFβ3 was subcloned into AAV. The recombinant plasmid AAV-TGFβ3 was transfected into H293 cells with LipofectamineTM 2000, and the expression of TGFβ3 gene was detected using immunofluorescent analysis. After AAV-TGFβ3 virus particle with infectious activity was packaged, TGFβ3 expression in NP cells was detected by immunoblotting, and its biological effect on proteoglycan synthesis was detected by antonopulos method and compared with that of AV-TGFβ1 in the earlier and later dedifferentiated NP cells. Results For the earlier dedifferentiated NP cells, AAV-TGFβ3 slowly and stably enhanced proteoglycan synthesis, but AV-TGFβ1 rapidly and transiently enhanced its synthesis. For the later dedifferentiated NP cells, AAV-TGFβ3 stably enhanced proteoglycan synthesis, but AV-TGFβ1 inhibited its synthesis. Conclusion AAV expression system can mediate TGFβ3 gene to be expressed stably, and AAV-TGFβ3 can enhance proteoglycan synthesis of the earlier and later dedifferentiated NP cells.     

CONSTRUCTING ADENO-ASSOCIATED VIRUS-TGFp3 AND COMPARING ITS BIOLOGICAL EFFECT ON PROTEOGLYCAN SYNTHESIS IN DEDIFFERENTIATED NUCLEUS PULPOUS CELLS WITH ADENOVIRUS-TGFβ1

Objective To construct adeno-associated virus (AAV) expression system for transforming growth factor β3 (TGFβ3) and detect its biological effect on proteoglycan synthesis of the earlier and later dedifferentiated rabbit lumbar disc nucleus pulpous (NP) cells, which was compared with that of adenovirus (AV) expression system for TGFβ1.Methods TGFβ3 gene was obtained using PCR. Its upstream contained restriction enzyme site Kpn Ⅰ, and its downstream contained restriction enzyme site Sal Ⅰ. Using the restriction enzyme sites of PCR product of TGFβ3 and the corresponding multiple cloning site (MCS) in plasmid AAV, TGFβ3 was subcloned into AAV. The recombinant plas-mid AAV-TGFβ3 was transfected into H293 cells with Lipofectamine(tm) 2000, and the expression of TGFβ3 gene was detected using immunofluorescent analysis. After AAV-TGFβ3 virus particle with infectious activity was packaged, TGFβ3 expression in NP cells was detected by immunoblotting, and its biological effect on proteoglycan synthesis was detected by antonopulos method and compared with that of AV-TGFβ, in the earlier and later dedifferentiated NP cells.Results For the earlier dedifferentiated NP cells, AAV-TGFβ slowly and stably enhanced proteoglycan synthesis, but AV-TGFβ, rapidly and transiently enhanced its synthesis. For the later dedifferentiated NP cells, AAV-TGFβ3 stably enhanced proteoglycan synthesis, but AV-TGFβ, inhibited its synthesis.Conclusion AAV expression system can mediate TGFβ3 gene to be expressed stably, and AAV-TGFβ3 can enhance proteoglycan synthesis of the earlier and later dedifferentiated NP cells.     

七氟醚和缺氧预适应诱导乳鼠心肌细胞HSP70表达的改变

目的 :探讨七氟醚预适应和缺氧预适应对乳鼠心肌细胞热休克蛋白 70表达的影响。方法 :第 2代培养心肌细胞随机分为正常对照组 (C组 )、缺氧 /复氧组 (A/R组 )、缺氧预适应组 (IP组 )和七氟醚预适应组 (S组 ) ,每组均缺氧 2h ,复氧 48h。分别取复氧 0 ,1,12 ,2 4,36和 48h的细胞 ,用免疫组化染色检测HSP70 表达并进行图象分析。结果 :在各个时间点 ,S组和IP组间的HSP70 表达均显著高于A/R组和C组 (P <0 .0 1) ,A/R组的HSP70 表达略高于C组 ,S组和IP组间的HSP70 表达差异无显著性 (P >0 .0 5 )。随着复氧时间的延长 ,S组和IP组间的HSP70 表达从 1h开始增加 ,2 4h表达最强 ,与 1h相比差异具有显著性 (P <0 .0 5 )。结论 :七氟醚预处理和缺氧预处理均可诱导乳鼠心肌细胞HSP70 在延迟相呈高表达 ,提示HSP70 参与了七氟醚预适应和缺氧预适应的延迟保护相。     

七氟醚和缺氧预适应诱导乳鼠心肌细胞HSP—70表达的改变

目的：探讨七氟醚预适应和缺氧预适应对乳鼠心肌细胞热休克蛋白70表达的影响。方法：第2代培养心肌细胞随机分为正常对照组(C组)、缺氧/复氧组(A／R组)、缺氧预适应组(IP组)和七氟醚预适应组(S组)，每组均缺氧2h，复氧48h。分别取复氧0，1，12，24，36和48h的细胞，用免疫组化染色检测HSP70表达并进行图象分析。结果：在各个时间点，S组和IP组间的HSP70表达均显著高于A／R组和C组(P＜0．01)，A／R组的HSP70表达略高于C组，S组和IP组间的HSP70表达差异无显著性(P＞0．05)。随着复氧时间的延长，S组和IP组间的HSP70表达从1h开始增加，24h表达最强，与1h相比差异具有显著性(P＜0．05)。结论：七氟醚预处理和缺氧预处理均可诱导乳鼠心肌细胞HSP70在延迟相呈高表达，提示HSP70参与了七氟醚预适应和缺氧预适应的延迟保护相。     

重组腺病毒介导的HSP70转染对肠上皮细胞缺氧再复氧损伤的防护作用

目的　研究重组腺病毒介导的热休克蛋白 70转染对肠上皮细胞缺氧再复氧损伤的保护作用。方法　将重组含人全长HSP70基因的腺病毒载体 (AdCMVHSP70 )转染体外培养的肠上皮细胞株IEC 6 ,检测转染细胞HSP70的基因表达水平。对照组 (转染空载体组 )、转染HSP70 2 4h、48h及72h组IEC 6细胞经缺氧再复氧处理后 ,分别对细胞的活力、凋亡及死亡水平进行检测分析。结果AdCMVHSP 70转染组细胞HSP70基因表达为阳性 ,对照组无表达。经缺氧再复氧处理后 ,AdCMVHSP70转染组细胞活力较对照组明显增强 (P <0 0 1 ) ,Annexin V Flous试剂盒检测死亡细胞明显减少 (P<0 0 1 ) ,凋亡有一定水平的抑制 (P <0 0 5)。结论　重组腺病毒介导的HSP70转染可保护肠上皮细胞抵抗缺氧再复氧损伤 ,具有明确的细胞保护作用。而其具体保护机制可能与抑制细胞凋亡有关     

HSP70在严重烧伤大鼠心肌中的表达及其保护作用的研究

目的 研究热休克蛋白70(HSP70)在严重烧伤大鼠心肌中的表达变化规律，并观察诱导热休克反应对烧伤后心肌损害的保护作用。方法 72只Wistar大鼠随机分为单纯烫伤组(B组)、亚砷酸钠预处理组(SA组)，于致伤前及30％TBSAⅢ度烫伤后3、6、12、24、48h检测血清心肌钙蛋白Ⅰ含量变化，Western blot检测心肌组织HSP70蛋白表达情况。结果 大鼠严重烧伤后3h心肌组织HSP70蛋白表达显著升高，伤后48h达高峰。大鼠烫伤后3h血清心肌钙蛋白Ⅰ(cTnⅠ)含量即开始明显升高，伤后12h达高峰。亚砷酸钠预处理可显著诱导机体的热休克反应，SA组伤后多数时相点血清cTnⅠ含量显著低于B组，且波动幅度较小。结论 严重烧伤早期即可引起心肌组织HSP70蛋白表达显著增强，HSP70蛋白可能在烧伤后早期心肌损害中发挥其内源性抗损伤机制。     

缺血预处理对鼠神经细胞HSP70、GFAP表达的影响

目的通过缺血预处理后大鼠局灶脑缺血模型观察神经细胞HSP70、GFAP变化。方法成年健康SD大鼠72只,随机分为预处理组、缺血组、假手术组,用大脑中动脉栓塞法制作脑缺血动物模型,每组在造模成功后24h、48 h、72 h取出大鼠脑组织。免疫组化（Immunohistochemistry,IHC）方法观察各个时间观察点HSP70蛋白和GFAP蛋白的表达。结果免疫组化结果显示,HSP70蛋白和GFAP蛋白大脑皮质等部位的细胞上呈阳性表达,其表达程度随时间延长存在明显差异。结论脑缺血预处理可上调大鼠神经细胞HSP70和GFAP的表达。     

腺病毒介导HSP70对大鼠缺血低氧脑组织保护作用

目的探讨外源性热休克蛋白70(HSP70)表达对脑缺血低氧模型大鼠脑组织保护作用。方法小鼠尾静脉注射携带全长HSP70基因vAd-HSP70,采用RT-PCR方法分别检测注射24、487、2 h后脑组织HSP70mRNA的转录水平。大鼠随机分为缺血低氧组(HI组)、vAd-HSP70静脉注射转染缺血低氧组(vAd-HSP70组,静脉注射转染vAd-HSP70的48 h后予缺血低氧处理)和正常对照组(NC组),各25只。用免疫组织化学技术对各组2、24、487、2 h及7 d脑组织中HSP70蛋白表达进行检测。结果小鼠尾静脉注射含HSP70重组腺病毒后可检测到HSP70基因的有效表达,且在注射48 h后表达水平最高,与247、2 h比较有显著性(F=18.58,P<0.05)。缺血低氧后大鼠脑组织中HSP70的水平增高,在缺血低氧后24 h达高峰,并在24~48 h内维持较高水平,以后逐渐下降。vAd-HSP70组HSP70各时间点的表达水平均高于HI组,在2、48、72 h差异有显著意义(F=85.36~866.67,q=6.71~88.43,P<0.05)。病理学检测显示HI组大鼠脑组织有较严重的缺血损伤性改变,vAd-HSP70组大鼠脑组织损伤较轻。结论外源性HSP70可在大鼠脑组织有效表达,并可减轻脑缺血低氧后病理损伤,对大鼠缺血低氧性脑损伤具有保护作用。     

新生大鼠脑缺氧缺血后海马CA1区HSP70表达及GM1作用

HI后新生大鼠海马CA1区仅能检出少量阳性HSP核蛋白(仅在核内表达的蛋白)，海马CA1区神经元呈较严重的缺血损伤性改变。而GM1组可见应激蛋白HSP70明显表达，24h达高峰。结论：GM1可使新生大鼠海马CA1区HSP70表达上调，减轻脑缺氧缺血后病理损伤，对新生大鼠缺氧缺血性脑损伤具有保护作用。     

热应激预处理缩短皮管断蒂时间的实验研究

目的:探讨热应激预处理对皮管的保护作用以及缩短皮管断蒂时间的可行性.方法:以Labrador犬为实验对象建立动物模型,行双侧下腹部皮管成形术,分为实验侧和对照侧进行自身对照,术后用红外线热疗仪对实验侧皮管局部加温进行热应激预处理,再分别延迟0 h、24 h、48 h、72 h、1周、2周皮管断蒂,对照侧皮管未经热应激预处理直接断蒂,每一时间段组各4只动物,断蒂7 d后观测比较两侧皮管存活情况,并用免疫组化ABC法观察两侧皮管组织中热休克蛋白70(heat shock protein 70,HSP70)的相应动态变化.结果:实验侧皮管组织内HSP70表达阳性,以热应激预处理后延迟24 h及48 h断蒂皮管的表达最强,对照侧则均呈阴性;24 h、48 h、72 h、1周和2周各时段,热应激预处理侧(实验侧)的皮管存活率大于对照侧,两者差异有统计学意义(P＜0.05).结论:热应激预处理对皮管具有保护作用,能够提高皮管断蒂以后的存活率,缩短皮管断蒂时间,其机制可能与热应激预处理后皮管HSP70的诱导合成有关.     

亚低温对大鼠脑缺血再灌注损伤后热休克蛋白70表达及细胞凋亡的影响

[目的]观察亚低温对大鼠局灶脑缺血再灌注损伤后热休克蛋白70(HSP70)表达的影响,探讨亚低温对脑神经细胞保护作用的机制。[方法]将SD大鼠随机分为正常组、假手术组、常温缺血组和亚低温缺血组。应用大脑中动脉线栓法(MCAO)建立大鼠局灶脑缺血再灌注模型,于缺血2 h再灌注,再灌注后3、6、12、24、72 h和7 d处死。其中亚低温组大鼠于缺血后30 min实施病灶侧脑亚低温并持续4 h。采用HE染色观察神经细胞形态学改变,免疫组化法检测脑组织HSP70表达,TUNEL法检测凋亡细胞。[结果]正常组及假手术组均未见明显病理改变;常温缺血组梗死灶明显,大量神经元坏死消失;亚低温缺血组未见明显梗死灶,但可见神经元固缩。正常组及假手术组未见或偶见HSP70阳性细胞;常温缺血组HSP70阳性细胞较多;与常温缺血组相比亚低温缺血组在相应时间点均明显减少(P<0.05)。常温缺血组TUNEL阳性细胞数随再灌注时间的延长而逐渐增多,至72 h达高峰;与常温缺血组相比,亚低温缺血组各时间点均明显减少(P<0.05)。[结论]亚低温对大鼠缺血再灌注损伤脑有保护作用,通过降低HSP70的表达和减少细胞凋亡可能是其保护机制之一。     

GM1对缺氧缺血新生大鼠脑损伤的保护作用

目的研究外源性单唾液酸四已糖神经节苷脂(monosialotetrahexosylgangtliosicle,GM1)对新生大鼠缺氧缺血性脑损伤(hypoxic—ischemic brain damage，HIBD)的保护作用。方法建立HIBD模型，观察腹腔注射GM，对HIBD模型鼠体重增长、脑水肿的影响，并用免疫组化及苏木素-伊红(HE)染色方法检测缺氧缺血(hypoxic—ischemic，HI)和GM1干预后不同时间点脑海马组织HSP70阳性细胞及病理学改变。结果HI后新生大鼠海马CA1区仅能检出少量阳性HSP核蛋白(仅在核内表达的蛋白)，海马CA1区神经元呈较严重的缺血损伤性改变。而GM1组体重增加、脑水肿减轻、可见应激蛋白HSP70明显表达。结论GM1可使新生大鼠海马CA1区HSP70表达上调，减轻脑水肿、减轻脑缺氧缺血后病理损伤，对新生大鼠缺氧缺血性脑损伤具有保护作用。