Activation and subcellular distribution of ERK1/2 following cerebral ischemia/reperfusion in rat hippocampus

Objective： To investigate the activation （phosphorylation） and subcellular localization of extracellular signal-regulated kinase （ERK1/2）, as well as the possible mechanism, following cerebral ischemia and ischemia/reperfusion in rat hippocampus. Methods： Transient brain ischemia was induced by the four-vessel occlusion method in Sprague-Dawley rats. Western blot analysis. Results： During cerebral ischemia without reperfusion ERK1/2 activation immediately increased with a peak at 5 min and then decreased in the cytosol fraction, which was paralleled by the increase of ERK1/2 activation in the nucleus fraction. During reperfusion, ERK1/2 was activated with peaks occurring at 10 min in the cytosol and at 30 min in the nucleus, respectively. Under those conditions, the protein expressions had no significant change. In order to clarify the possible mechanism of ERK1/2 activation, the rats were intraperitoneally administrated with N-methyl-D-aspartate （NMDA） receptor antagonist dextromethorphan （DM）, L-type voltage-gated Ca^2＋ channel （L-VGCC） antagonist nifedipine （ND） 20 rain before ischemia, finding that DM and ND markedly prevented ERK1/2 activation of nucleus fraction induced by reperfusion, not by ischemia. Conclusion： These results suggested that the nuclear translocation mainly occurred during ischemia, while ischemia-reperfusion induced ERK1/2 activation both in the cytosol and the nucleus. Two type calcium channels contributed, at least partially, to the activation of ERK1/2.     

Role of mitogen-activated protein kinases in the regulation of paraventricular nucleus to gastric ischemia-reperfusion injuries

Background We investigated the role in electrical stimulations of paraventricular nucleus （PVN） on gastric mucosal cells and the activity of mitogen-activated protein kinases （MAPKs） family members induced by gastric ischemia-reperfusion （GI-R）. And we elucidated the molecular mechanisms of the protection of PVN from GI-R injuries. Methods Sprague-Dawley rats were divided randomly into 4 groups： Group I, the sham-operated GI-R control group; Group II, the sham-operated electrical stimulations to PVN ＋ sham-operated GI-R control group; Group III, the GI-R group; and Group IV, the electrical stimulations to PVN ＋ GI-R group. In all of the experiments, the PVN was stimulated prior to the induction of GI-R. The GI-R model was established by clamping the celiac artery for 30 minutes to induce ischemia and then was released to allow reperfusion for 30 minutes, 1 hour, 3 hours and 6 hours, respectively. The gastric mucosal cellular apoptosis, proliferation, and the expression and activity of MAPKs protein were observed by immunohistochemistry and Western blotting, respectively. Results Compared with the GI-R group, the application of electrical stimulations in the PVN significantly depressed gastric mucosal cellular apoptosis and enhanced gastric mucosal cellular proliferation following the 30-minute, 1-hour and 3-hour intervals of reperfusion; it also promoted the activation of p-ERK during the early phase of reperfusion but inhibited the activation of p-JNK1/2 and p-p38 following the 30-minute, 1-hour and 3-hour intervals of reperfusion. Conclusions The protection of PVN against GI-R injuries may attribute to the inhibition of apoptosis and the promotion of the proliferation of gastric mucosal cells during GI-R. This protective effect is mediated by activating the ERK pathway and depressing the JNK, the JNK. p38 MAPK oathwavs of the oastric mucosal cells.     

Parathyroid hormone-mitogen-activated protein kinase axis exerts fibrogenic effect of connective tissue growth factor on human renal proximal tubular cells

Background Enhanced and prolonged expression of connective tissue growth factor （CTGF） is associated with kidney fibrosis. Parathyroid hormone （PTH） is involved in the genesis of disturbed calcium/phosphate metabolism and ostitis fibrosa in renal failure. PTH activated mitogen-activated protein kinase （MAPK） signaling pathway is present in renal tubular cells. The aim of this study was to identify the mechanism how the signal is transduced to result in extracellular signal-regulated protein kinase （ERK） activation, leading to upregulation of CTGF.Methods The levels of CTGF mRNA and protein in human kidney proximal tubular cells （HK-2） treated with PTH in the presence or absence of the MAPK inhibitor PD98059 were analyzed by quantitative real-time polymerase chain reaction （RT-PCR） and immunoblotting assay. The activation of the CTGF promoter in HK-2 cells was determined by the dual-luciferase assay. The effects of the protein kinase A （PKA） activator 8-Br-cAMP and protein kinase C （PKC） activator phorbol 12-myristate 13-acetate （PMA） on MAPK phosphorylation, and the effects of the PKA inhibitor H89 and PKC inhibitor calphostin C on MAPK phosphorylation and CTGF expression were detected by immunoblotting assay.Results PD98059 inhibited the PTH stimulated expression of CTGF, which strongly suggested that the MAPK signaling pathway plays an important role in the PTH-induced CTGF upregulation in renal tubular cells. A PKA activator as well as PKC activators induced MAPK phosphorylation, and both PKA and PKC inhibitors antagonized PTH-induced MAPK phosphorylation and CTGF expression.Conclusion CTGF expression is upregulated by PTH through a PKC/PKA-ERK-dependent pathway.     

NO调控JNKs通路对鼠海马神经元保护作用研究

Background C-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether the activation of JNK1/2 is associated with the production of endogenous nitric oxide. Methods Ischemia and reperfusion was induced by cerebral four-vessel occlusion (4-VO). Sprague–Dawley (SD) rats were divided into 6 groups: sham group, ischemia and reperfusion group, neuronal nitric oxide synthase (nNOS) inhibitor 7-Nitroindazole (7-NI) (Sigma St Louis, MO, USA) given group, inducible nitric oxide synthase (iNOS) inhibitor (AMT) (Sigma) given group, sodium chloride control group and 1% dimethyl sulfoxide (DMSO) control group. The levels of protein expression and phospho-JNK1/2 were detected by western blot and the survival hippocampus neurons in CA1 zone were observed by cresyl violet (CV) staining. Results The study illustrated two peaks of JNK1/2 activation occurred at 30 min and 3 days during reperfusion. 7-NI inhibited JNK1/2 activation during the early reperfusion, whereas AMT preferably attenuated JNK1/2 activation during the later reperfusion. At same time, the results also showed that administration of 7-NI and AMT can decrease ischemia/Reperfusion (I/R)-induced neuronal loss in hippocampal CA1 region. Conclusions JNK1/2 activation is associated with endogenous nitric oxide (NO) in response to ischemic insult.     

Role of protein tyrosine kinase in IL-1β induced activation of mitogen-activated protein kinase in fibroblast-like synoviocytes of rheumatoid arthritis

Objectives To study mitogen-activated protein kinase (MAPKs) activation in fibroblast-like synoviocytes (FLS) of rheumatoid arthritis (RA) under the stimulation of IL-1β, and to elucidate the role of protein tyrosine kinase (PTK) in the activation of MAPKs. Methods Primary cultures of RA FLS were used. Western blot was applied to examine transient changes in protein tyrosine phosphorylation status and MAPKs activation in RA FLS stimulated with IL-1β at various doses, and over different periods. Genistein, the specific PTK inhibitor, was used to evaluate the inhibitory role in activation of MAPKs by IL-1β.Results IL-1β transiently increased protein tyrosine phosphorylation, and activated the MAPKs cascades (mainly ERK(2), JNK(2) and P(38)) in RA FLS. There was no obvious difference in MAPKs activation among different doses of IL-1β (1 IU/ml,10 IU/ml, 100 IU/ml), but the peak activation of ERK(2), JNK(2) and P(38)took place at 5 min, 15 min and 1 min, respectively, after stimulation with IL-1β. The activation of ERK(2)was inhibited by genistein, but the inhibitory role on that of JNK and P(38)was relatively weak. Conclusions During signal transduction of IL-1β in RA FLS, tyrosine phosphorylation was increased transiently, the MAPKs cascade was activated in a few minutes, and there was heterogenicity in the activation among three subfamily members. PTK had a role in the activation of ERK, but had weak effects on that of JNK and P(38).     

Effects of mitogen-activated protein kinase signal pathway on heat shock protein 27 expression in human lens epithelial cells exposed to sodium salicylate in vitro

The roles of mitogen-activated protein kinase （MAPK） signal pathway in sodium salieylate-induced expression of heat shock protein 27 （HSP27） in human lens epithelial cells （HLECs-B3） in vitro were investigated. HLECs-B3 were incubated in the fresh media containing sodium salicylate at different concentrations for different durations, and allowed to be recovered in fresh medium without sodium salicylate for different durations with or without pretreatment with p38MAPK inhibitor （SB203580）, ERK1/2 inhibitor （PD98059） and JNK/SAPK inhibitor （SP600125）. The expression of P38MAPK, ERK1/2, JNK/SAPK, phosphorylated P38MAPK, phosphorylated ERK1/2, phosphorylated JNK/SAPK and HSP27 was detected by Western blot. The expression of HSP27 mRNA and protein was detected by RT-PCR and immunohistochemistry respectively. It was found there was only weak expression of HSP27 in normal HLECs. The expression of HSP27 was not detectable in HLECs-B3 that were exposed to sodium salicylate （55 retool/L） for 1-5 h. It was indicated that recovery from sodium salicylate （〉35 mmol/L） significantly increased the synthesis of HSP27. The expression of HSP27 was up-regulated in HLECs-B3 under sodium salicylate recovery for 3 h, reached the peak level for 6 h, and returned to the level of control cells by 24 h. Activation of P38MAPK from sodium salicylate stimulation occurred at 30th rain, and increased significantly at 1st h, then declined and renamed to baseline level at 3rd h under sodium salicylate recovery. Activation of ERK1/2 occurred at 1st h and reached the peak level at 6th h under sodium salicylate recovery. However, JNK/SAPK was inactivated by sodium salicylate. The expression of HSP27 could be down-regulated with the pretreatment of SB203580 and PD98059 jointly. It is concluded that sodium salicylate can induce the expression of HSP27 in HLECs-B3. The effects are mediated, at least in part, through the activation of P38MAPK and ERK1/2 signaling pathway.     

Mitogen-activated protein kinase-dependent apoptosis in norcan-tharidin-treated A375-S2 cells is proceeded by the activation of protein kinase C

Background We have reported that norcantharidin (NCTD) induces human melanoma A375-S2 cell apoptosis and that the activation of caspase and the mitochondrial pathway are involved in the apoptotic process. This study aimed at investigating the roles of mitogen-activated protein kinase (MAPK) and protein kinase C (PKC) in A375-S2 cell apoptosis induced by NCTD.Methods We assessed the effects of NCTD on cell growth inhibition using the 3-(4,5-dimethyhhiazol-2-yl)-2,5-dipheyhetrazolium bromide (MTT) assay, DNA fragmentation (DNA agarose gel electrophoresis), and MAPK protein levels (Western blot analysis) in A375-S2 cells. Photomicroscopic data were also collected.Results The NCTD inhibitory effect on A375-S2 cells was partially reversed by MAPK and PKC inhibitors.The expression of phosphorylated JNK and p38 also increased after the treatment with NCTD, and inhibitors of c-Jun NH2 -terminal kinase (JNK) and p38 (SP600125 and SB203580, respectively) had significant inhibitory effects on the upregulation of phosphorylated JNK and p38 expression. Simultaneously, the PKC inhibitor staurosporine blocked the upregulation of phosphorylated JNK and phosphorylated p38, but had little effect on extracellular signal-regulated kinase (ERK) expression.Conclusion These results suggest that the activation of JNK and p38 MAPK promotes the process of NCTDinduced A375-S2 cell apoptosis and that PKC plays an important regulation role in the activation of MAPKs.     

Differential activation of mitogen—activated protein kinases by γ—irradiation in IEC—6 cells：Role of intracelluklar Ca^2＋

Abstract Objective:To explore the effects of γ-irradiation on mitogen-activatedprotein kinases(MAPKs) and role intracellular calcium in this event in intestinal epithelial cell line 6(IEC-6 cells).Methods:After cultured rat IIEC-6 cells with or without the pretreatment of intracellular Ca^2 chelator were exposed to γ-ir-radiation of 6 Gy, the total and phosphorylated MAPKs in the cells were determined with Western blotting and apoptosis was examined with flow cytometry.Activities of Extracellular signal-regulated protein kinase (ERK) and p38 MAPK were determined by using immuoprecipitation followed by Western blotting.Results:In response to γ-irradiation,phosphorylation of ERK was not significantly observed ,while the levels of phos-phorylated c-Jun NH2-terminal kinase(JNK) and p38 MAPK were increased in 30 min and reached the peak 2h after exposure to 6Gy γ-irradiation,though the cell viability was significantly lowered 12h.On the other hand, no obvious changes were seen in the total protein levels of ERK, JNK and p38 MAPK.Chelation of in-tracellular Ca^2 almost completely suppressed the JNK and p38 MAPK phosphorylation induced by γ-irradiation is a potent activator for JNK and p38 MAPK, and Ca^2 mobilized from intracellular stores plays an important role in the activation of MAPKs and the induction of apoptosis in IEC-6 cells.     

Increased vulnerability of hypertrophied myocardium to ischemia and reperfusion injury. Relation to cardiac renin-angiotensin system.

Hearts of pressure-verload hypertrophy show an increased activation of intracardiac renin-angiotensin system which may contribute to ischemia and reperfusion injury. The purpose of this study is to evaluate whether the hypertrophied myocardium is more vulnerable to ischemia and reperfusion injury and to find out its relation to the cardiac renin-ngiotensin system. Hypertrophied rat hearts induced by abdominal aortic banding for 6 weeks were subjected to 2 hours of hypothermic ischemic arrest followed by 30 minutes of reperfusion, and their cardiac function recovery was compared with that of sham-operated normal control hearts. The cardiac renin activity and angiotensin Ⅱ content before ischemia and after reperfusion were determined. It was found that both the pre-schemic renin activity and angiotensin Ⅱ level were higher in hypertrophied myocardium than those in the control: ischemia and reperfusion injury increased both renin activity and angiotensin Ⅱ content in the two groups, but the renin activi     

Mediterranean diet may reduce risk of diabetes

Background Nitric oxide （NO） is a biologically active molecule which has been reported to protect the heart against ischemia and reperfusion injury in different species. This study aimed to test the hypothesis that nitric oxide may induce the expression of heat shock protein 72 （HSP72） which may protect the heart against ischemia.
Methods Rabbits were given intravenous saline or S-nitroso-N-acetylpenicillamine （SNAP）, a nitric oxide donor, or Zaprinast, an inhibitor of cyclic guanosine monophosphate （GMP）-phosphodiesterase, which may increase myocardial cyclic GMP content. Twenty-four hours later, the rabbits were either sampled to measure HSP72, or induced with a 30-minute coronary occlusion followed by a 120-minute reperfusion, and then the infarct size was measured. Meanwhile, chelerythrine （CHE, an inhibitor of protein kinase C） was given intravenously 5 minutes before SNAP injection and the effect on HSP72 expression and infarct size was determined.
Results Twenty-four hours after pretreatment, immunoblotting showed HSP72 expression increased in the SNAP group compared with control groups, and this was blocked by CHE. Myocardial infarct size in the SNAP group was smaller than that of the control group （（32.4±5.8）% vs （51.1±4.7）%, P 〈0.05）. Pretreated with CHE abolished the infarct size-limiting effect of SNAP （（46.0±5.1）%）. Pretreatment with Zaprinast neither induced HSP72 expression nor reduced infarct size （（55.4±5.4）%）.
Conclusion NO induced HSP72 expression and a delayed protection to the heart via the activities of protein kinase C by a cyclic GMP-independent pathway.     

蝙蝠葛酚性碱对脑缺血大鼠细胞凋亡相关蛋白PKB表达的影响

目的:探讨蝙蝠葛酚性碱(phenolic alkaloids fromMenispermum dauricum,PAMD)预处理对脑缺血后大脑皮质细胞凋亡蛋白激酶B(protein kinase B,PKB)表达的影响。方法:采用线栓阻塞大脑中动脉方法制备大鼠脑缺血模型,并用受试药物术前连续预处理模型大鼠7 d。采用免疫组织化学方法测定假手术组,模型组,PAMD高、中、低剂量组,尼莫地平、银杏叶片预处理组大鼠缺血后24,48,72 h大脑皮质中细胞凋亡相关蛋白PKB表达变化。结果:行大脑中动脉闭塞后大鼠大脑皮质PKB均被诱导表达,PAMD预处理7 d后,缺血后各时间点大鼠大脑皮质PKB表达明显升高。结论:PAMD能明显促进缺血脑损伤后抑制细胞凋亡相关蛋白PKB表达水平,从而在缺血性脑损伤中起到神经保护作用。     

JNK蛋白在全脑缺血再灌注损伤中的表达

目的:探讨大鼠全脑缺血再灌注氨基末端激酶或应激活化激酶(JNK)蛋白表达的变化。方法:构建大鼠全脑缺血再灌注模型,采用TUNEL法原位检测凋亡锥体细胞,免疫印迹检测不同实验组中JNK蛋白表达。结果:缺血再灌注各组神经元细胞的凋亡率明显高于假手术组(P<0.05)。缺血再灌注组JNK蛋白表达积分光密度值与假手术组相比有显著差异(P<0.05)。结论:在脑缺血及再灌注损伤中存在JNK途径的过度激活,进而导致神经元细胞的凋亡明显增加。     

磷酸肌醇信号通路与心肌缺血关系的研究

目的　利用心肌缺血模型,研究磷酸肌醇4激酶（PI 4 kinase）、磷酸肌醇磷酸激酶（PIP 5 Kinase）和蛋白酶C（PKC）在心肌缺血过程中的变化,以探讨磷酸肌醇信号系统在心肌缺血过程中调控的机理.方法　建立大鼠体内心肌缺血模型,利用同位素标记方法在蛋白水平上分别检测心肌组织缺血后不同时间（缺血后1、8、25、48小时）磷酸肌醇4-激酶（PI 4 kinase）、磷酸肌醇磷酸激酶（PIP 5 Kinase）和蛋白酶C（PKC）活性的变化.结果　心肌组织中,磷酸肌醇4-激酶、磷酸肌醇磷酸激酶和蛋白酶C的活性在心肌缺血后1小时迅速达到最高值,分别为对照组活性的6.1、3.0和4.0倍,差异明显；随后酶活性水平开始下降,48小时已经接近对照组水平.结论　磷酸肌醇信号途径参与心肌缺血过程的调控,但其调控机理有待于进一步研究.     

磷酸肌醇信号通路与心肌缺血关系的研究

目的：利用心肌缺血模型，研究磷酸肌醇4激酶（PI4kinase）、磷酸肌醇酸激酶（PIP5Kinase）和蛋白酶C(PKC)在心肌缺血过程中的变化，以探讨磷酸肌醇信号系统在心肌缺血过程中调控的机理。方法：建立大鼠体内心肌缺血模型，利用同位素标记方法在蛋白水平上分别检测心肌组织缺血后不同时间（缺血后1、8、25、48小时）磷酸肌醇4-激酶（PI4kinase）、磷酸肌醇磷酸激酶（PIP 5Kinase）和蛋白酶C(PKC)活性的变化。结果：心肌组织中，磷酸肌醇4-激酶、磷酸肌醇磷酸激酶和蛋白酶C的活性在心肌缺血后1小时声速达到最高值，分别为对照组活性的6.1、3.0和4.0倍，差异明显；随后酶活性水平开始下降，48小时已经接近对照组水平。结论：磷酸肌醇信号途径参与心肌缺血过程的调控，但其调控机理有待于进一步研究。     

蛋白激酶C在缺血预处理大鼠肾脏缺血再灌注损伤中的表达

目的 探讨蛋白激酶Ｃ在缺血预处理大鼠肾脏因再灌注损伤中的作用。方法 将大鼠随要分组,观察大鼠肾脏病理组织学变化,用免疫组织化学方法检测不没灌注时间蛋白激酶Ｃ水平。结果 预处理后缺血再灌注组病理组织学肾小管评分均低于缺血再灌注,而预处理后缺血再灌注组和对照组之间无显性差异;预处理后缺血再灌注组蛋白激酶Ｃ的表达高于缺血再灌注组,并且在再灌注２小时和６小时时,预处理后缺血再灌注组中的表达高于对照组。结     

肺缺血再灌注损伤时丝裂原活化蛋白激酶(MAPKs)活性的变化及意义

目的探讨肺缺血再灌注损伤时丝裂原活化蛋白激酶（MAPKs）活性的变化规律及意义。方法取健康Sprague-Dawley大鼠建立在体肺缺血再灌注模型，左肺门夹闭30min，复灌0、10、30、60、90、120min，采用蛋白免疫印迹法（Westernblot）检测肺组织中3种丝裂原活化蛋白激酶（MAPKs）：ERK（extracellular signal regulated protein kinase，ERK1／2）、JNK（c—Jon NH2-terminal protein kinase，JNK）和p38MAPK在假手术对照（Sham）组、缺血30min和缺血后再灌注不同时间点的活性变化。结果与假手术对照组相比，ERK、JNK的活性随缺血和再灌注时间的延长而逐渐升高直到复灌120min。p38的活性只在缺血及缺血早期激活而在复灌30rain后活性恢复至假手术对照组水平。缺血／再灌注各时点组间ERK、P38、JNK蛋白水平差异无统计学意义（P＞0．05）。结论3种丝裂原活化蛋白激酶（MAPKs）在肺缺血再灌介导细胞凋亡中发挥不同的作用。     

Association of the phosphatidylinositol signal pathway with prolonged myocardial ischemia

Ｉｎ 1986 ,Ｍｕｒｒｙ ,ｒｅｐｏｒｔｅｄｏｎｅｎｄｏｇｅｎｏｕｓｐｒｏｔｅｃｔｉｖｅｍｅｃｈａｎｉｓｍ ,ｔｈｅｓｏ ｃａｌｌｅｄ“ｉｓｃｈｅｍｉｃｐｒｅｃｏｎｄｉｔｉｏｎ” 1Ｗｈｉｌｅｎｕｍｅｒｏｕｓｓｔｕｄｉｅｓｈａｖｅｆｏｃｕｓｅｄｏｎｔｈｉｓｍｅｃｈａｎｉｓｍｏｆｉｓｃｈｅｍｉｃｐｒｅｃｏｎｄｉｔｉｏｎｉｎｇ ,ｆｅｗｐｅｏｐｌｅｎｏｔｉｃｅｄｔｈｅｏｒｇａｎｉｓｍ’ｓｒｅｓｐｏｎｓｅｔｏｐｒｏｌｏｎｇｅｄｉｓｃｈｅｍｉａ Ｉｔｗａｓａｌｓｏｄｅｍｏｎｓｔｒａｔｅｄｔｈａｔｐｒｏｔｅｉｎｋｉｎ…     

蛋白激酶C抑制剂对脑缺血大鼠突触体游离钙的影响

目的：探讨蛋白激酶Ｃ（Ｐｒｏｔｅｉｎ ｋｉｎａｓｅ Ｃ,ＰＫＣ）参与神经损伤机制。方法：采用大鼠全脑缺血模型,观察脑缺血／再灌流后突触体游离钙的变化及ＰＫＣ的抑制剂灯盏花对突触体游离钙的影响。结果：脑缺血／再灌流可以导致突触体游钙增加的抑制剂灯盏花可以阻止脑缺血／再灌流导致突触体游离钙增加。结论：ＰＫＣ参与神经元缺血性损伤可能与其促进钙内流有关。     

蛋白激酶C和蛋白酪氨酸激酶活性对缺血再灌注心肌细胞凋亡影响的实验研究

为探讨缺血预适应（Ｉｓｃｈｅｍｉｃ Ｐｒｅｃｏｎｄｉｔｉｏｎｉｎｇ,ＩＰ）早期以及蛋白激酶Ｃ（Ｐｒｏｔｅｉｎ Ｋｉｎａｓｅ Ｃ,ＰＫＣ）及蛋白酷氨酸激酶（Ｐｅｏｔｅｉｎ Ｔｙｒｏｓｉｎｅ Ｋｉｎａｓｅ,ＰＴＫ）激动剂和抑制剂对缺血再灌注（Ｉ／Ｒ）心肌细胞凋亡的影响以及ＩＰ效能发挥通路中央ＰＫＣ和ＰＴＫ的关系。用ＴＵＮＥＬ法检测Ｉ／Ｒ心肌细胞凋亡。结果显示：１、ＩＰ早期能显著降低Ｉ／Ｒ心肌细胞凋亡（     

蛋白激酶C激活调控Bcl-2与缺血诱导神经元凋亡关系的研究

目的：探讨蛋白激酶C激活参与神经元凋亡的可能机理。方法：采用大鼠全脑缺血模型，观察脑缺血／再灌流后蛋白激酶C活性、Bcl-2表达及神经元凋亡的变化。结果：脑缺血／再灌流可以导致蛋白激酶C的移位激活伴Bcl-2表达及神经元凋亡的增加；用蛋白激酶C抑制剂灯盏花可以阻止上述变化。结论：蛋白激酶C的激活促进Bcl-2表达可能与脑缺血／再灌流诱导的神经元凋亡有关。