断肢再植肌组织缺血再灌注损伤的细胞凋亡表达

目的研究断肢再植过程中缺血性损伤和缺血再灌注损伤的发生情况和病理改变，探讨细胞凋亡表达规律。方法建立大鼠后肢断肢实验模型，以光镜观察缺血和缺血再灌注早期的骨骼肌组织病理变化，以TUNEL（POD法）检测缺血和缺血再灌注过程中细胞凋亡现象的发生。结果缺血5h的大鼠断肢再植全部存活，而缺血9h者未存活。大鼠断肢再植过程中，缺血性和缺血再灌注性损伤引起骨骼肌细胞水肿、坏死和细胞凋亡，并于再灌注过程观察到微循环障碍和中性粒细胞趋化浸润现象，缺血7h凋亡率最高。结论骨骼肌存在缺血性和缺血再灌注性损伤，细胞凋亡是缺血和缺血再灌注损伤的重要病理改变。骨骼肌缺血再灌注过程存在微循环障碍和中性粒细胞趋化浸润，它们是缺血再灌注损伤的重要原因之一。     

17-β雌二醇对大鼠肝切除肝缺血再灌注损伤肝细胞凋亡和Bcl-2、Bax表达的影响

目的 观察17-β雌二醇预处理对肝切除肝缺血再灌注损伤肝脏组织细胞凋亡及Bcl2、Bax表达的影响,并探讨其肝保护的机制.方法 建立大鼠肝切除肝缺血再灌注损伤模型,75只雄性SD大鼠随机分为3组:假手术组(Sham组)、缺血再灌注组(IR组)和17-β雌二醇预处理组(E2+ IR组).检测各组大鼠再灌注后lh、3h、6h、12 h、24 h肝功能变化.光镜下观察肝组织病理学改变.TUNEL法观察再灌注后12 h大鼠肝细胞凋亡情况、流式细胞学方法测定再灌注后12h肝细胞凋亡率.Western blot法检测再灌注后12 h Bcl-2和Bax的表达情况.结果 与Sham组相比,在IR组各时间点均可见ALT和AST增高,且在再灌注后的12h达到了最高值;病理学检查可见肝细胞肿胀,肝窦变窄,嗜中性粒细胞浸润和片状坏死等变化;在再灌注后12h,凋亡细胞增多及细胞凋亡率明显升高;肝脏组织Bcl 2表达减少,Bax的表达增加.17-β雌二醇预处理组在灌注后各时间点ALT和AST值明显下降,肝脏病理损伤改善;在再灌注后12h,凋亡细胞减少及细胞凋亡率明显降低,肝脏组织Bcl-2表达增加,Bax的表达减少.结论 17-β雌二醇对大鼠肝缺血再灌注损伤有明显的保护作用,其可能通过促进Bcl-2表达及抑制Bax表达,从而抑制肝细胞凋亡.     

大鼠小肠缺血再灌注后血中NO和SOD浓度与肺损伤的相关性研究

目的：探讨大鼠小肠缺血再灌注后血中-氧化氮（NO），超氧化物歧化酶（superoxidediamu—tase，SOD）的浓度变化与肺组织中Bax、Bcl-2、p53的表达及肺组织超微结构变化的相关性。方法：建立小肠缺血再灌注模型，分为对照组，再灌注后0、30min，1、2h，1、3、7d共8组，于各时相点检测血中NO和SOD的浓度，用免疫组织化学SP法观察肺组织中Bax、Bcl-2、p53的表达情况，透射电子显微镜观察肺组织细胞超微结构变化。结果：大鼠小肠缺血再灌注后0rainNO浓度升高，但至再灌注2h时则明显阳氏，其后又持续升高，至再灌注7d时达高峰。SOD浓度在再灌注0min明显下降，再灌注2h时升高，随后持续下降，至再灌注7d时达最低水平。Bax、Bcl-2免疫阳性细胞主要位于肺组织中血管内皮细胞和肺泡上皮细胞。再灌注0min，Bax、Bcl-2阳性细胞表达率升高，30min时其阳性细胞表达率均分别升高为17．1％和78．1％，Bcl-2表达高于Bax（P〈0．01）。2h时降低，其后升高，7d时阳性细胞表达率达到高峰，分别为94．1％和83．4％，Bax表达明显高于Bcl-2（P〈0．01）。透射电子显微镜显示肺组织细胞超微结构损伤改变。结论：血中NO、SOD浓度变化和肺组织中超微结构的改变说明小肠缺血再灌注后可引起肺组织细胞凋亡和损伤，而大鼠小肠缺血再灌注后Bax、Bcl-2、p53在肺组织细胞中的阳性表达均有明显改变并可能引起细胞凋亡和损伤。     

肢体缺血-再灌注损伤时细胞凋亡的变化及阿魏酸钠保护作用

目的：阐明氧自由基与细胞凋亡、Bcl-2和Bax蛋白表达在大鼠肢体缺血及再灌注不同时相中的变化规律和相互关系，探讨阿魏酸钠对肢体缺血-再灌注损伤的影响。方法：采用大鼠股动脉夹闭模型，设立缺血组、对照组及阿魏酸钠组，测定肌肉组织中丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性，检测肌肉组织中Bcl-2和Bax蛋白表达的变化，观察细胞凋亡现象。结果：随着再灌注时间的延长(24h内)，氧自由基水平、凋亡指数(AI)及Bax蛋白表达水平进行性升高，阿魏酸钠组三者水平低于对照组；Bcl-2蛋白在短时间内升高，而后逐渐下降，阿魏酸钠组Bcl-2蛋白表达水平的峰值低于对照组，下降也较对照组平缓，至再灌注24h时，阿魏酸钠组Bcl-2蛋白表达水平已高于对照组；氧自由基、Al之间呈显著正相关，氧自由基、Al与Bcl-2／Bax比值呈显著负相关。结论：氧自由基及细胞凋亡同时参与肢体缺血-再灌注损伤，氧自由基可能通过调节Bcl-2／Bax两蛋白的比例关系而发挥其促进细胞凋亡的作用，阿魏酸钠可以有效清除自由基，抑制细胞凋亡，减轻肢体再灌注损伤。     

缺血后处理对鼠肝缺血再灌注损伤细胞凋亡及Bcl-2和Bax表达的影响

目的观察缺血后处理对肝脏缺血再灌注损伤后早期肝组织细胞凋亡及Bcl-2和Bax表达的影响,并探讨其肝保护的机制。方法建立大鼠肝脏缺血再灌注模型,54只雄性SD大鼠随机分为假手术组（SO组）、缺血再灌注组（IR组）和缺血后处理组（IPC组）。以缺血再灌注前反复多次的短暂预再灌注及停灌注作为后处理。分别于再灌注后1、3、6h测定血清肝酶,SP免疫组化法测定肝脏Bcl-2和Bax表达水平,TUNEL法检测肝组织中凋亡细胞。结果与SO组相比,IR组肝酶活性升高,Bcl-2表达降低,Bax表达升高并可见明显的细胞凋亡;而IPC组同IR组相比,肝酶活性降低,Bcl-2表达升高,Bax表达降低,凋亡指数（AI）下降,差异均有统计学意义。结论缺血后处理对大鼠肝脏缺血再灌注损伤有明显的保护作用,可通过促进Bcl-2表达及抑制Bax表达而拮抗肝细胞凋亡,从而减轻肝脏缺血再灌注损伤。     

异丙酚对大鼠小肠缺血再灌注时粘膜上皮细胞凋亡的影响

目的 探讨异丙酚对大鼠小肠缺血再灌注时粘膜上皮细胞凋亡的影响及其机制.方法 健康Wistar大鼠24只,随机分为3组(n=8):假手术组(S组)、缺血再灌注组(I/R组)和异丙酚+缺血再灌注组(P+I/R组).夹闭肠系膜上动脉,缺血1 h,再灌注2 h,制备小肠缺血再灌注损伤模型.S组和I/R组缺血前10 min开始经股静脉持续输注生理盐水10 ml·kg-1·h-1,P+I/R组静脉注射异丙酚10 mg/kg,以后持续输注异丙酚10 mg·kg-1·h-1.取空肠组织3 cm,常规制备全层石蜡切片,行HE染色,光镜下观察小肠组织病理学;免疫组化法检测Bcl-2、Bax蛋白的表达;TUNEL法检测小肠粘膜上皮细胞凋亡,计数凋亡细胞及总细胞,计算小肠粘膜上皮细胞凋亡指数.结果 与S组比较,I/R组和P+I/R组Bcl-2和Bax蛋白表达上调,Bcl-2/Bax增加,小肠组织损伤程度增强,小肠粘膜上皮细胞凋亡指数增高(P＜0.01或0.05);与I/R组比较,P+I/R组Bcl-2蛋白表达上调,Bax蛋白表达下调,小肠组织损伤程度减轻,小肠粘膜上皮细胞凋亡指数降低(P＜0.01).结论 异丙酚可减轻大鼠小肠缺血再灌注损伤时粘膜上皮细胞凋亡,其机制与上调Bcl-2基因的表达和下调Bax基因的表达有关.     

阿魏酸钠抑制缺血性急性肾衰竭肾小管上皮细胞凋亡

目的：探讨阿魏酸钠对缺血性急性肾衰竭大鼠肾脏小管上皮细胞凋亡的影响及机制。方法：将雄性SD大鼠随机分为假手术组、缺血再灌注组、阿魏酸钠冶疗组、SOD冶疗对照组。观察肾组织病理改变；免疫组化、RT—PCR检测Bax，Bcl-2的表达；采用原位DNAg-断末端标记法（TUNEL）检测肾组织细胞凋亡。结果：大鼠肾脏缺血45min再灌注24h，大鼠肾功能损害明显，肾脏组织病理学改变明显，肾小管上皮细胞凋亡明显，肾组织Bax蛋白、mRNA的表达上调，Bcl-2蛋白、mRNA的表达下调。应用阿魏酸钠干预后。改变与上述相反。结论：在缺血性急性肾衰竭中，阿魏酸钠减轻肾脏缺血再灌注桶伤．减轻肾脏细胞凋亡．缓解肾功能桶害．奠作用至少部分通过调控凋亡相关基因Bcl-2家族基因的表达。     

兔心肌缺血-再灌注后c-fos,PCNA,Bax和Bcl-2的表达及临床意义

目的研究新西兰大白兔心肌细胞缺血-再灌注后原癌基因（c-fos）、增殖细胞核抗原（PCNA），Bax基因，Bcl-2基因的表达及其临床意义。方法用18只新西兰大白兔建立心肌缺血-再灌注模型，按不同再灌注方法随机分为3组，每组6只。Ⅰ组，缺血15min，不灌注；Ⅱ组，缺血15min，再灌注15min；Ⅲ组，缺血15min，再灌注30min。术后分别取缺血-再灌注区及对照区（非缺血-再灌注区）心肌组织进行c-fos，PCNA，Bax，Bcl-2的免疫组织化学检测。结果3组心肌细胞缺血-再灌注后c-fos、PCNA、Bax和Bcl-2均有阳性表达，缺血-再灌注区均高于对照区（P〈0．01或〈0．05）；组间比较：缺血-再灌注区c-fos、Bax和Bcl-2阳性率Ⅱ组、Ⅲ组均高于Ⅰ组，且Ⅲ组高于Ⅱ组（P〈0．01），PCNA阳性率Ⅲ组高于Ⅰ组（P〈0．01）。3组缺血-再灌注区Bax／Bcl-2比值均较对照区增高。结论心肌缺血和再灌注显著诱导c-fos的表达，其增加与心肌再灌注损伤有关；心肌缺血-再灌注后诱发细胞促凋亡／抗凋亡相关基因Bax／Bcl-2的激活，存在着与增殖基因共同表达的特点。     

吸入麻醉药预处理对兔缺血再灌注心肌Bcl-2、Bax及p53基因表达的影响

目的探讨吸入异氟醚、七氟醚及地氟醚预处理对兔在体心脏局部缺血再灌注过程中心肌细胞Bcl-2、Bax及p53基因表达的影响。方法 40只新西兰白兔随机分成5组(n=8):假手术对照组(P组)、缺血再灌注对照组(IR组)、异氟醚预处理组(Ⅰ组)、七氟醚预处理组(S组)、地氟醚预处理组(D组)。除P组外,每组接受左冠脉前降支3 h阻断和3 h再灌注。吸入药预处理组在缺血前分别吸入1MAC的异氟醚、七氟醚或地氟醚,30 min后洗脱15 min。取心肌缺血区边缘组织用流式细胞仪测凋亡指数(AI)和Bcl-2、Bax及p53基因的蛋白表达量。结果 AI:P组为(0.93±0.27)％,IR组为(14±4)％,I、s、D组较IR组显著减少,分别为(6.7±1.8)％、(6.7±1.6)％、(7.4±2.0)％(P<0.01)。Bcl-2、p53、Bax基因的蛋白表达:Bcl-2基因的蛋白表达量I、S、D组高于IR组,Bax基因和p53基因的蛋白表达量I、S、D组低于IR组。结论 异氟醚、七氟醚及地氟醚预处理抑制缺血再灌注所致心肌细胞凋亡与上调BcI-2基因的蛋白表达、下调p53和Bax基因的蛋白表达有关。     

依托咪酯后处理对大鼠脑缺血再灌注时细胞凋亡的影响

目的 评价依托咪酯后处理对大鼠脑缺血再灌注时细胞凋亡的影响.方法 清洁级健康雄性SD大鼠32只,体重250～300 g,采用随机数字表法,将大鼠随机分为4组(n=8):假手术组(S组)、缺血再灌注组(I/R组)、脂肪乳组(L组)和依托咪酯后处理组(Ep组).采用栓塞右侧大脑中动脉2h恢复灌注的方法制备大鼠脑缺血再灌注模型.Ep组于再灌注即刻腹腔注射依托咪酯乳剂20 mg/kg(1 ml/100 g),I/R组和L组分别给予等容积生理盐水和脂肪乳.于再灌注24h时处死大鼠,取缺血侧脑组织,HE染色后光镜下观察病理学结果,采用TUNEL法检测凋亡细胞,计算凋亡指数,采用免疫组化染色法测定Bcl-2和Bax的表达,计算Bcl-2与Bax表达的比值(Bcl-2/Bax).结果 与S组比较,I/R组、L组和Ep组细胞凋亡指数升高,Bcl-2和Bax表达上调,Bcl-2/Bax升高(P＜0.05);与I/R组和L组比较,Ep组细胞凋亡指数降低,Bcl-2表达上调,Bax表达下调,Bcl-2/Bax升高(P＜ 0.05);I/R组和L组上述指标差异无统计学意义(P＞0.05).Ep组脑组织病理学损伤较I/R组明显减轻.结论 依托咪酯后处理减轻大鼠脑缺血再灌注损伤的机制与调节Bcl-2和Bax的平衡表达,抑制细胞凋亡有关.     

Difference of molecular response to ischemia-reperfusion of rat skeletal muscle as a function of ischemic time: study of the expression of p53, p21(WAF-1), Bax protein, and apoptosis.

The authors investigated the expression of p53, p21(WAF-1), Bax protein, and apoptosis to elucidate the cellular response to ischemia-reperfusion of skeletal muscle using the rat lower limb model. The rat left lower limb was dissected in the inguinal region, isolating the bony femoral muscles, and the femoral vessels were clamped to produce an ischemic condition. After 3 or 6 hours, the clamps were removed and the gastrocnemius muscle was resected at various times up to 72 hours after reperfusion. Five specimens of the muscle were obtained at each time point from 5 rats. When any rat died during the study, additional rats were used until 5 specimens could be obtained from 5 rats at each time point. The expression of three proteins was detected by Western blot analysis. The apoptotic cells were detected using terminal deoxytransferase-mediated dUDP (deoxyuridine[-5']diphosphate) nick-end labeling assay. Histopathological study showed severe interstitial edema and leukocyte infiltration at 6 hours of ischemia compared with 3 hours of ischemia. Moreover, at 6 hours of ischemia, muscle fiber fragmentation was observed at 72 hours after reperfusion whereas no fragmentation was found at 3 hours of ischemia. At 3 hours of ischemia, p53 and p21(WAF-1) accumulated after reperfusion, and there was a time lag in the time of onset of elevation and the peak time point between these two proteins. The level of Bax protein did not elevate and the rate of apoptotic cells did not increase. At 6 hours of ischemia, p53 and p21(WAF-1) also accumulated, but the kinetics of p21(WAF-1) were similar to that of p53 in the time of onset of elevation and the peak time point after reperfusion. In addition, the level of Bax protein increased and apoptosis was induced. These results demonstrated that p53 and p21(WAF-1) accumulated after 3 and 6 hours of ischemia of skeletal muscle during reperfusion. Moreover, it was demonstrated that the kinetics of induced p53, p21(WAF-1) and Bax protein differ between 3 hours and 6 hours of ischemia, and it is speculated that this difference plays an important role in determining the consequence of the cell exposed to ischemia.     

Molecular response to ischemia-reperfusion of rat skin: study of expression of p53, p21WAF-1, and Bax proteins, and apoptosis

The authors investigated the expression of p53, p21WAF-1, and Bax proteins, and apoptosis to elucidate the cellular response to ischemia-reperfusion of the skin. The rat left lower limb was dissected at the inguinal region retaining the bone and femoral vessels, and the vessels were clamped to produce an ischemic condition. After 6 hours the clamps were removed, and the plantar skin was resected at various times up to 72 hours after reperfusion. Five skin specimens were obtained at each time point from 5 rats. When a rat died during the study, additional rats were used until five specimens could be obtained from 5 rats at each time point. The expression of the three proteins was detected by Western blot analysis. The apoptotic cells were detected using the terminal deoxytransferase-mediated dUDP nick-end labeling assay. After reperfusion, the levels of p53 and p21WAF-1 were significantly higher in the ischemia-reperfusion rats compared with the sham-operated rats. However, the levels of Bax protein did not show a noticeable increase at any period. The apoptotic cells in both the epidermis and dermis were not evident compared with the sham skin, which were similar to those in the nontreated, normal skin. These results demonstrate that p53 and p21WAF-1 proteins accumulate after 6 hours of ischemia of the skin during reperfusion. Moreover, it is speculated that accumulation of these proteins plays an important role in the survival of the skin by inducing growth arrest of the cells, but not apoptosis.     

大白鼠小肠缺血再灌注后肾脏组织中凋亡基因表达与超微结构改变

目的:探讨大白鼠小肠缺血再灌注后肾脏组织的次级损伤和改变。方法:建立小肠缺血再灌注模型,于缺血再灌注前及再灌注后03、0 min,1、2 h,1、3、7天采取静脉血并切取脏肾组织块;用化学法检测一氧化氮(NO)和超氧化物歧化酶(SOD)血中含量,用免疫组织化学SP法和透射电镜分别观察肾脏组织中Bax、Bcl-2、p53的表达及细胞超微结构的改变情况。结果:小肠缺血再灌注后NO浓度有所升高(P<0.01),而SOD浓度呈下降趋势(P<0.01)。Bax、Bcl-2及p53免疫阳性细胞率于再灌注0 min开始升高,依次为(3.35±1.43)%,(2.86±0.56)%,(1.58±0.32)%;至30 min时,三者阳性细胞率升高更为明显,依次为(13.38±3.65)%,(22.25±4.82)%,(6.31±2.24)%,但Bcl-2表达高于Bax(P<0.01)。再灌注2 h时,三种基因的表达均有所降低,其后又开始升高,7天时阳性细胞率达高峰,依次为(59.85±8.25)%,(40.75±6.27)%,(36.45±4.98)%,但Bax表达明显高于Bcl-2。电镜观察发现肾小管基底膜破裂,上皮坏死脱落等。结论:大鼠小肠缺血再灌注后可引起肾脏组织细胞的凋亡和损伤。     

Implications of p53 protein expression in experimental spinal cord injury

In order to clarify the role of p53, known as a tumor suppressor protein and also as a key molecule of apoptotic cell death, we have studied p53 expression in relation to localization, time course, cell type, and TUNEL reaction in a rat model of transectional spinal cord injury. Other apoptosis related molecules, p21, Bcl-2 and Bax, that are in the cascade of p53 pathway, were also examined. p53 was expressed in cells residing in the vicinity of transection as early as 30 min. For the next 2 days, the positive cells spread in distribution, increased in number, and thereafter decreased. p53 immunoreactivity was localized primarily to the nucleus but not to cytoplasm. Double-staining with glial cell markers revealed that p53 immunoreactivity was often co-localized in microglia, oligodendrocytes and astrocytes, but not in neurons. In view of the results of the double-staining of p53 and Bcl-2, Bax or TUNEL, a variety of apoptosis-related molecules are expressed with p53, all within the first three days of injury. Further, the process of apoptosis via the p53, pathway appears complex even in this simple model of CNS injury. Our study suggests that the manipulation of these apoptosis-related molecules may prove useful in modifying the cell and tissue damage in traumatic CNS injury.     

缺血后处理对大鼠骨骼肌缺血再灌注损伤的影响

目的 探讨缺血后处理对大鼠骨骼肌缺血再灌注损伤的影响以及应用缺血后处理的时机.方法 将32只大鼠随机分成四组,采用切断患肢全部皮肤、肌肉和神经,保留患肢股动静脉的动物模型,通过夹闭和开放股动静脉造成骨骼肌缺血和再灌注损伤.采用测定骨骼肌缺血4 h.再灌注1 h后血清丙二醛(MDA)、骨骼肌髓过氧化物酶(MPO),再灌注6 h后骨骼肌的死亡程度来观察缺血后处理对大鼠骨骼肌缺血再灌注损伤的影响,以及再灌注5 min后应用缺血后处理是否对骨骼肌缺血再灌注损伤有保护作用.结果 对骨骼肌缺血4 h再灌注6 h的损伤,再灌注开始后即刻应用30 s缺血、30 s再通,三次循环的缺血后处理对骨骼肌的缺血再灌注损伤即有保护作用,不仅减少了骨骼肌再灌注区域中性粒细胞浸润(MPO)和血清氧自由基水平(MDA)水平,而且减少了骨骼肌的死亡程度;再灌注5 min后应用缺血后处理并没有降低骨骼肌缺血再灌注区域的MPO和血清MDA水平,也没有降低骨骼肌缺血再灌注后的死亡程度,与直接缺血再灌注组相同,对骨骼肌缺血再灌注损伤并没有保护作用.结论 骨骼肌缺血后再灌注开始前立刻应用缺血后处理对大鼠骨骼肌缺血再灌注损伤有一定的保护效果,可以减少骨骼肌缺血再灌注损伤后的死亡程度;缺血后处理应用时机非常重要,再灌注5 min后应用缺血后处理则失去对骨骼肌缺血再灌注损伤的保护作用.     

The long-term effect of sevoflurane on neuronal cell damage and expression of apoptotic factors after cerebral ischemia and reperfusion in rats

We investigated the long-term effects of sevoflurane on histopathologic injury and key proteins of apoptosis in a rat hemispheric ischemia/reperfusion model. Sixty-four male Sprague-Dawley rats were randomly assigned to Group 1 (fentanyl and N2O/O2; control) and Group 2 (2.0 vol% sevoflurane and O2/air). Ischemia (45 min) was produced by unilateral common carotid artery occlusion plus hemorrhagic hypotension (mean arterial blood pressure 40 mm Hg). Animals were killed after 1, 3, 7, and 28 days. In hematoxylin and eosin-stained brain sections eosinophilic hippocampal neurons were counted. Activated caspase-3 and the apoptosis-regulating proteins Bax, Bcl-2, Mdm-2, and p53 were analyzed by immunostaining. No eosinophilic neurons were detected in sevoflurane-anesthetized rats over time, whereas 9%-38% of the hippocampal neurons were eosinophilic (days 1-28) in control animals. On days 1 and 3, the concentration of Bax was 140%-200% larger in fentanyl/N2O-anesthetized animals compared with sevoflurane. Bcl-2 was 100% less in control animals during the first 3 days. Activated caspase-3 was detected in neurons of both groups (0.75%-2.2%). These data support a sustained neuroprotective potency of sevoflurane related to reduced eosinophilic injury after cerebral ischemia/reperfusion.     

Augmenter of Liver Regeneration Attenuates Tubular Cell Apoptosis in Acute Kidney Injury in Rats: The Possible Mechanisms

Augmenter of liver regeneration (ALR), the expression of which increased in rat kidneys after renal ischemia/reperfusion (I/R) injury, enhances renal tubular cell regeneration in vivo and in vitro. We aimed to investigate the effects of ALR on apoptosis of renal tubular cells after renal I/R injury in vivo and consider the possible mechanisms. Rats that were subjected to bilateral renal ischemia for 60 min followed by reperfusion were administered with either vehicle or recombinant human ALR (rhALR). Renal dysfunction and histologic injury were assessed by the measurement of serum biochemical markers and histological grading. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). Caspase-3 activity was measured using a colorimetric protease assay. Expression of Bcl-2, Bax Fas, phosphorylated-Akt (p-Akt), and phosphorylated-p53 (p-p53) was determined by western blotting. Compared with vehicle-treated rats, renal dysfunction and histologic injury were significantly attenuated by administration of rhALR. The number of TUNEL-positive tubular cells and caspase-3 activity were decreased, Bcl-2 and p-Akt expression was up-regulated, and Bax and p-p53 expression was down-regulated by administration of rhALR. However, administration of rhALR had no effect on Fas protein expression. These results indicate that the protective effect of rhALR on renal I/R injury is associated with its anti-apoptotic action in renal tubular cells. RhALR inhibits apoptosis by increasing the ratio of Bcl-2 to Bax and by decreasing the activity of caspase-3. The activation of Akt and inactivation of p53 are involved in the rhALR anti-apoptosis process.