糖尿病大鼠肾组织VEGF和TGF-β1的动态表达及意义

目的动态观察链脲佐菌素(STZ)诱导的糖尿病大鼠肾组织中血管内皮生长因子(VEGF)及转化生长因子β1(TGF-β1)的表达情况,探讨它们在糖尿病肾病(DN)发生发展中的作用及其相互关系。方法实验动物随机分为5组,依病程长短分为:(1)A组(2周组);(2)B组(4周组);(3)C组(8周组);(4)D组(16周组);(5)E组(24周组),每组分别设有正常对照组(N组)和糖尿病组(DM组)。注射STZ法复制糖尿病大鼠模型;免疫组织化学方法检测肾组织VEGF、TGF-β1及纤连蛋白(FN)的表达;PAS染色光镜观察肾小球系膜、肾小管基底膜变化及细胞外基质沉积情况等的形态学改变;生化方法测定血糖、血肌酐及24h尿蛋白量。结果(1)正常对照组大鼠肾组织VEGF和TGF-β1均有少量表达,而糖尿病大鼠肾组织两者的表达均显著高于正常对照组。(2)糖尿病16周时肾组织VEGF表达与TGF-β1呈正相关。(3)随糖尿病进展,细胞外基质纤连蛋白(FN)在肾小管及肾小球表达增多,24h尿蛋白也增多,并且VEGF、TGF-β1两者都分别和FN、24h尿蛋白呈正相关性。结论糖尿病肾病大鼠肾组织中VEGF及TGF-β1参与了早晚期蛋白尿及肾脏肥大硬化的发生,并且VEGF和TGF-β1相互作用,共同促进了肾病的发生发展。     

氯沙坦对糖尿病大鼠肾小管转化生长因子β_1及蛋白激酶Cβ表达的影响

目的探讨血管紧张素受体拮抗剂氯沙坦在糖尿病大鼠早期肾损伤中的保护作用及其机制。方法将36只实验动物随机分为正常对照组、糖尿病组及氯沙坦治疗组。链脲佐菌素(STZ)60 m g/kg制作糖尿病动物模型,检测各组大鼠的血糖、血肌酐、尿白蛋白、肾脏肥大指数的变化,免疫组织化学检测转化生长因子1β(TGF-1β)、蛋白激酶Cβ(PKCβ)的表达水平。结果治疗第8周末,氯沙坦治疗组较非治疗组白蛋白明显减少(P<0.01),肾脏肥大指数改善(P<0.05),免疫组织化学显示,糖尿病组大鼠肾小管TGF-1β和PK Cβ蛋白表达增多,氯沙坦治疗组TG F-1β和PKCβ蛋白表达均明显减少。结论氯沙坦对糖尿病早期肾脏病变有一定的保护作用,其机制可能是通过下调糖尿病大鼠TGF-1β和PKCβ的表达实现的。     

阿托伐他汀对糖尿病大鼠血脂和肾功能的影响

目的 :探讨阿托伐他汀对糖尿病大鼠肾脏的保护作用及其机制。方法 :将SD大鼠随机分为正常对照组(C组 )、糖尿病组 (D组 )、阿托伐他汀治疗组 (DT组 )。检测各组大鼠在灌胃给药第 4、第 8周时血糖、糖化血红蛋白(HbA1c)、血胆固醇、三酰甘油、高密度脂蛋白、血肌酐、尿素氮、尿白蛋白、血转化生长因子 (TGF β1)浓度及体重等指标的变化 ,免疫组化检测纤维连接蛋白 (FN)和层黏连蛋白 (LN)表达水平。结果 :第 8周时 ,DT组大鼠血胆固醇、三酰甘油、肌酐、TGF - β1浓度及尿白蛋白排泄率较D组明显减少 (P <0 0 1或 <0 0 5 ) ;免疫组化显示 ,DL组大鼠肾小球FN和LN的表达明显低于D组 (P <0 0 1或 <0 0 5 )。结论 :阿托伐他汀对于糖尿病大鼠肾脏具有部分保护作用 ,其可抑制血TGF - β1浓度的升高 ,下调糖尿病大鼠TGF β1的表达 ,减少细胞外基质的沉积。     

黄芪对糖尿病大鼠肾组织NF-κB和MCP-1表达的影响

目的 研究(NF-κB)和(MCP-1)在糖尿病肾病(DN)大鼠肾组织中的变化并探讨黄芪对NF-κB和MCP-1表达的影响及其对糖尿病大鼠肾脏的保护作用.方法 将大鼠随机分成正常对照组(C组)、糖尿病组(DM组)、糖尿病黄芪组(DT组);生化法测定血肌酐及24 h尿蛋白;免疫组织化学法检测各组大鼠肾组织NF-κB、MCP-1的表达.结果 C组肾小球NF-κB及MCP-1在有少量表达,DT组肾小球中NF-κB、MCP-1表达较DM组有下降(P<0.05):DM组血肌酐和24 h尿蛋白较C组升高(P<0.01),而DT组较DM组明显降低(P<0.05);DT组较DM组病理学损害有改善.结论 黄芪能减少尿蛋白、延缓肾功能进展、改善肾组织病理学损害,对糖尿病肾病大鼠有治疗作用,其机制之一可能是通过抑制NF-κB的活化和MCP-1表达而实现的.     

氯沙坦对糖尿病大鼠肾脏结构、功能及肾组织p38MAPK的影响

目的　探讨特异性血管紧张素ⅡⅠ型受体拮抗剂氯沙坦对糖尿病大鼠肾脏结构、功能的保护机制及p38MAPK信号转导通路对此过程的作用。方法　♂Wister大鼠行右肾切除术 2wk后 ,随机分为 3组 ,右肾切除对照组、糖尿病组 ,氯沙坦治疗组。腹腔注射链脲佐菌素 (STZ ,6 5mg·kg-1)诱发糖尿病模型 ,氯沙坦 4 0mg·kg-1·d-1灌胃。分别于注射STZ后 4wk后各组选取 6只大鼠 ,收集尿液 ,测定尿蛋白(Upro) ,尿肌酐 (Ucr) ;股动脉放血分离血清 ,测定血糖(Glu)、血尿素氮 (BUN) ,血肌酐 (Scr)并计算肌酐清除率(Ccr)。免疫组化检测肾皮质磷酸化p38蛋白激酶 (p p38MAPK)及磷酸化cAMP反应元件结合蛋白 (p CREB)的表达特征 ,纤维粘连蛋白 (fibronectin ,FN )及层粘连蛋白(laminin ,LN)的表达 ,应用图像分析系统进行半定量分析。Westernblot及流式细胞术定量检测 p p38MAPK和 p CREB蛋白的表达。结果　与对照组相比 ,4wk时糖尿病模型组肾小球基底膜轻度增厚 ,细胞外基质 (ECM )增多 ,系膜区扩大 ,肾脏肥大指数升高 ,肾功能轻度受损 ,p p38MAPK、p CREB、FN及LN表达明显升高 ;而与糖尿病模型组相比 ,氯沙坦组肾脏结构 ,功能及各指标的表达有不同程度的降低。结论　氯沙坦对糖尿病大鼠肾脏结构和功能具有保护作用 ,可能是通过调     

氯沙坦对早期糖尿病肾病大鼠的保护作用

目的：探讨氯沙坦对大鼠早期实验性糖尿病肾病的肾保护作用。方法：将30只雄性Wistar大鼠随机分为3组，即正常对照组(N组)、糖尿病模型组(D组)、糖尿病＋氯沙坦(T组)，每组10只。于第4，8周末测定3组大鼠的肌酐清除率(Ccr)、24 h尿蛋白。于第8周末处死大鼠，作肾皮髓质一氧化氮(NO)、超氧化物歧化酶(SOD)含量测定，同时作光镜、电镜、免疫组化(转化生长因子β1，TGFβ1检查。结果：T组Ccr、24 h尿蛋白较D组显著降低，皮髓质NO、SOD含量明显高于D组，肾内TGFβ1表达明显下降，病理变化较D组也明显减轻。结论：氯沙坦能改善糖尿病大鼠肾内血流动力学紊乱，下调TGFβ1的表达，增加NO、SOD的含量，改善糖尿病肾病的病理变化。     

灯盏花素对糖尿病大鼠肾脏蛋白激酶Cα和肿瘤坏死因子α表达的影响

目的:探讨灯盏花素(breviscapine,Bre)对链脲佐菌素(STZ)诱导的糖尿病大鼠肾脏蛋白激酶Cα(PKCα)、肿瘤坏死因子α(TNFα)表达的影响。方法:采用SD大鼠尾静脉注射STZ45 mg.kg-1建立实验性糖尿病模型。将成模DM大鼠随机分成:糖尿病模型组(DM组)、灯盏花素治疗组(Bre-L组,10 mg.kg-1.d-1;Bre-H组,20 mg.kg-1.d-1),同时设正常对照组(NC组)。治疗8周后检测各组大鼠血糖(FBG)、肾指数、肌酐(SCr)、尿素氮(BUN)、尿白蛋白排泄率(UAER)、HE染色光镜观察肾脏形态结构,采用免疫组化方法检测肾脏PKCα、TNFα表达情况。结果:与DM组比较,Bre组大鼠血糖无明显变化,但肾指数、Scr、BUN、UAER均明显降低,光镜下肾脏结构亦明显改善,肾组织PKCα、TNFα的表达显著减少。结论:Bre对糖尿病大鼠肾脏具有一定的保护作用,可能与其抑制糖尿病大鼠肾脏PKCα、TNFα表达有关。     

丝裂原活化蛋白激酶38在糖尿病小鼠肾组织中的表达

目的研究丝裂原活化蛋白激酶38（p38MAPK）在链脲左菌素（STZ）诱导的糖尿病小鼠肾组织中的表达及活化情况,从分子信号角度探讨糖尿病肾病。肾纤维化的发病机制。方法采用STZ腹腔注射诱导小鼠糖尿病模型,并检测血糖、血肌酐、24h尿白蛋白排泄率、肾小球细胞外基质;用免疫组织化学方法检测糖尿病小鼠肾组织磷酸化p38MAPK和TGFβ的表达,用RT-PCR的方法检测肾组织p38MAPK和TGFβmRNA的表达。结果腹腔注射STZ后,模型组小鼠均出现明显的多食、多饮、多尿和体质量下降等糖尿病症状,血糖明显升高,血肌酐水平明显增高,24h尿白蛋白排泄率明显增加,肾小球细胞外基质明显增宽。正常。肾组织有基础的磷酸化p38MAPK和p38MAPKmRNA表达,糖尿病形成后4周,磷酸化p38MAPK和p38MAPKmRNA在肾组织中的表达明显增高,并持续增加到8周,第12周至16周磷酸化p38MAPK和p38MAPKmRNA的表达有所减少。正常肾组织有基础的TGFβ1蛋白和mRNA表达。糖尿病形成后4周,TGFβ1蛋白和mRNA在。肾组织中的表达均明显增高,并持续增加到12周,第16周肾组织TGFβ1的表达有所减少。肾组织磷酸化p38MAPK和TGFβ1的表达趋势一致,并呈明显正相关（r=0．64,P〈0．01）,且与肾小球细胞外基质的积聚密切相关。结论p38MAPK的表达和活化可能通过介导TGFβ1的表达参与了小鼠糖尿病肾病模型肾纤维化的发生。     

缬沙坦对高糖培养的肾小球系膜细胞p38MAPK传导通路的影响

目的探讨高糖状态下肾小球系膜细胞中p38丝裂原活化蛋白激酶(p38 MAPK)、其上游因子MAPK激酶3/6(MKK3/6)和下游因子cAMP反应元件结合蛋白1(CREB1)的表达以及血管紧张素受体1拮抗剂(AT1Ra)缬沙坦的影响。方法体外培养大鼠肾小球系膜细胞,分别给予高糖和缬沙坦干预,采用Western bolt检测MKK3/6、p38 MAPK和CREB1及其磷酸化蛋白的表达,逆转录-聚合酶链反应(RT-PCR)检测系膜细胞内TGF-β1和FN mRNA的表达。放免法测定细胞上清液中纤维连接蛋白(FN)和IV型胶原的含量。MTT法检测缬沙坦在不同时间、不同药物浓度对细胞增殖状态的影响。结果①与低糖对照组相比,高糖组系膜细胞p-p38 MAPK、p-MKK3/6和p-CREB1表达明显上调,TGF-β1和FN mRNA的表达增加,FN和IV型胶原含量增加。②缬沙坦组p-p38 MAPK、p-MKK3/6和p-CREB1的表达明显下调,TGF-β1和FN mRNA的表达降低,同时FN和IV型胶原的含量减少。③MTT法检测显示不同浓度的缬沙坦对细胞增殖状态都有所抑制,并随药物浓度的增加而作用增强。结论缬沙坦抑制肾小球系膜细胞TGF-β1的表达和细胞外基质的分泌可能部分是通过影响p38 MAPK传导通路的激活来实现的。     

福辛普利与氯沙坦对实验性糖尿病大鼠肾病的防治作用与转化生长因子β_1的关系

目的探讨转化生长因子β1(TGFβ1)与糖尿病肾病之间的关系及血管紧张素转换酶抑制剂福辛普利和血管紧张素Ⅱ受体拮抗剂氯沙坦对肾小球病变的保护作用与机制。方法建立糖尿病大鼠模型,分为正常对照(A组)、糖尿病组(B组)、福辛普利治疗组(C组)、氯沙坦治疗组(D组),检测第1、2、4、12周血糖、24h尿TGFβ1排泄率以及Alb排泄率。于第4周、第12周处死大鼠获取肾,计算肾脏肥大指数,分离皮髓质,检测肾皮质TGFβ1蛋白水平及皮质TGFβ1mRNA水平。结果①尿Alb排泄率与尿TGFβ1排泄率:各实验组尿Alb排泄率与尿TGFβ1排泄率随病程延长进一步增加,二种药物治疗均可使尿Alb排泄率与尿TGFβ1排泄率明显减少,但不能使其恢复正常。②免疫组化结果显示各实验组大鼠肾皮质TGFβ1蛋白含量较对照组显著增加,随病程延长增加更加明显,二种药物治疗组大鼠肾皮质TGFβ1蛋白含量较B组明显减少。③各时期肾皮质TGFβ1mRNA的表达量B组最高,C、D组大鼠肾皮质TGFβ1蛋白含量较B组明显减少,早期以C组减少更为明显。肾皮质TGFβ1mRNA的表达量与尿TGFβ1排泄率呈正相关。结论肾脏TGFβ1mRNA及其蛋白表达的上调可能是糖尿病肾病的发生机制之一,尿TGFβ1排泄率可以作为诊断早期糖尿病肾病和评价病变程度的标志物之一。福辛普利、氯沙坦具有确切肾脏保护作用,且福辛普利早期作用较氯沙坦更为明显。这种作用部分与其抑制肾脏TGFβ1过度表达有关。     

Cocaine treatment- and withdrawal-induced alterations in the expression and serine phosphorylation of the NR1 NMDA receptor subunit

Abstract Rationale. Repeated administration of cocaine alters the expression of the NMDA receptor subunits, NR1 and NR2B in a region- and withdrawal time-dependent manner. Objective. The present experiments extend these findings by characterizing the effects of cocaine withdrawal on specific NR1 splice variant expression. In addition, changes in the serine phosphorylation of NR1 and in the expression of postsynaptic density protein, PSD-95, were measured as potential molecular mechanisms for the cocaine-induced alterations in receptor subunit expression. Methods. Rats were injected with either saline or cocaine for 7 consecutive days and were sacrificed 24 h or 14 days following the last injection. Brain regions putatively identified in mediating the behavioral and neurochemical effects of cocaine, such as the frontal cortex, neostriatum, and hippocampus, were microdissected and used for immunoblotting experiments. In addition, drug-induced changes in NR1 phosphorylation in frontal cortex were investigated using immunohistochemistry. Results. After 2 weeks of withdrawal from cocaine, NR1 subunit expression in the neostriatum was down-regulated ~27%, as compared to saline-treated control rats. Further, at 24 h but not 14 days of withdrawal, phosphorylation of serine residues 896 and 897 was reduced ~34% in the frontal cortex of rats treated with cocaine, as compared to controls. Conclusions. Results suggest that early changes in kinase or phosphatase activity may contribute to prolonged cocaine-induced alterations in NR1 expression. Thus, NR1 phosphorylation could be important for the activation of pathways that are substrates for the effects of cocaine exposure and withdrawal. Electronic Publication     

Ganoderma atrum polysaccharide evokes antitumor activity via cAMP-PKA mediated apoptotic pathway and down-regulation of Ca2+/PKC signal pathway

Ganoderma atrum polysaccharide (PSG-1) has been commonly suggested as a candidate for prevention and therapy of cancer. We investigated the antitumor effect and the underlying molecular mechanisms of PSG-1. The results showed that PSG-1 inhibited tumor growth and resulted in tumor cell apoptosis in vivo. Here, the data revealed that PSG-1 caused a markedly increase in cAMP and PKA activities, rather than cGMP and PKC. Moreover, the treatment of PSG-1 induced a dramatic increase in the protein level of PKA. In contrast, the expression of PKC and intracellular [Ca²⁺]_i were inhibited. Our study also revealed that treatment with PSG-1 increased the spleen and thymus weights, lymphocyte proliferation and macrophage phagocytic activity in tumor-bearing mice. Taken together, we conclude that PSG-1 could inhibit the tumor growth, possibly in part by enhancing the induction of apoptosis through cAMP-PKA signaling pathway and down-regulation of Ca²⁺/PKC signal pathway, activating host immune function in S180-bearing mice.     

Roles of protein kinase A and C in the opioid potentiation of the GABAA response in rat periaqueductal gray neuron

The periaqueductal gray (PAG) is the main target site of the opioid-induced analgesia. The present study was designed to examine the roles of protein kinase A (PKA) and C (PKC) in the opioid-induced modulation of the currents activated by an inhibitory neurotransmitter, gamma-aminobutyric acid (GABA). The PAG neurons were acutely isolated and voltage-clamped under the nystatin-perforated patch-clamp mode. The GABA-activated current was sensitively blocked by a GABA(A) receptor antagonist, bicuculline, and selectively carried by chloride ions. The GABA(A) receptor-activated Cl(-) current was potentiated by a mu-opioid receptor agonist, [D-Ala(2),N-MePhe(4),Gly(5)-ol]-enkephalin acetate (DAMGO). The GABA response was also potentiated by phorbol-12-myristate-13-acetate (PMA). Pretreatment with PMA occluded the DAMGO potentiation. However, both chelerythrine and 2-[1-(3-dimethylaminopropyl)indol-3-yl]-3-(indol-3-yl) maleimide (GF109203X) also potentiated the GABA response. Pretreatment with chelerythrine or GF109203X also occluded the DAMGO potentiation. Meanwhile, the GABA response was potentiated by N-(2-[p-bromocinnamylamino]-ethyl)-5-isoquinolinesulfonamide (H-89), while not altered by forskolin. Pretreatment with H-89 occluded the potentiation effect of DAMGO on the GABA response. In addition, the DAMGO effect was completely blocked by pretreatment with forskolin. From the result, it can be suggested that activation of mu-opioid receptor potentiates the GABA(A) response through the mediation of PKA inhibition, and that PKC is not directly involved in the action mechanism of DAMGO.     

(-)棉酚和(+)棉酚对蛋白激酶C及蛋白激酶A活力影响的比较

部分纯化的大鼠肝脏蛋白激酶C和蛋白激酶A,在体外与棉酚的旋光异构体分别温育,结果(--)棉酚和(+)棉酚对蛋白激酶C活力均有剂量依赖性的抑制作用;(-)棉酚对Ⅰ型蛋白激酶A活力的抑制作用明显比(+)棉酚强,而(-)棉酚和(+)棉酚在高浓度时对Ⅱ型蛋白激酶A才显示抑制作用。结果提示棉酚在体内可能干扰细胞信息的传递过程。     

Effects of electroshock and drugs administered in vivo on protein kinase activity in rat brain.

The effect of electroshock and treatment with reserpine, amphetamine or lithium chloride on protein kinase activity in synaptic membrane fragments prepared from rat brain was investigated. Naive rats subjected to electroshock procedures showed significant increases in both basal and cyclic AMP-stimulated activity irrespective of whether the treatment was sham, acute or chronic. These increases did not occur in animals which had been tamed by daily handling for 15 days prior to treatment, suggesting that the response was induced by the stress of an unfamiliar situation. Administration of lithium chloride and reserpine caused a small but significant increase in the stimulated activity. Doses of d-amphetamine of 5 mg/kg had no effect on either basal or stimulated activity, but higher doses (up to 15 mg/kg) resulted in a pronounced increase in both activities, which may have been related to drug-induced stress.     

Role of protein kinase D signaling in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with dismal survival rates. Its intransigence to conventional therapy renders PDAC an aggressive disease with early metastatic potential. Thus, novel targets for PDAC therapy are urgently needed. Multiple signal transduction pathways are implicated in progression of PDAC. These pathways stimulate production of intracellular messengers in their target cells to modify their behavior, including the lipid-derived diacylglycerol (DAG). One of the prominent intracellular targets of DAG is the protein kinase C (PKC) family. However, the mechanisms by which PKC-mediated signals are decoded by the cell remain incompletely understood. Protein kinase D1 (PKD or PKD1, initially called atypical PKCμ), is the founding member of a novel protein kinase family that includes two additional protein kinases that share extensive overall homology with PKD, termed PKD2, and PKD3. The PKD family occupies a unique position in the signal transduction pathways initiated by DAG and PKC. PKD lies downstream of PKCs in a novel signal transduction pathway implicated in the regulation of multiple fundamental biological processes. We and others have shown that PKD-mediated signaling pathways promote mitogenesis and angiogenesis in PDAC. Our recent observations demonstrate that PKD also potentiates chemoresistance and invasive potential of PDAC cells. This review will briefly highlight diverse biological roles of PKD family in multiple neoplasias including PDAC. Further, this review will underscore our latest advancement with the development of a potent PKD family inhibitor and its effect both in vitro and in vivo in PDAC.     

Glutamate-mediated spinal reflex potentiation involves ERK 1/2 phosphorylation in anesthetized rats

The extracellular signal-regulated kinase (ERK) cascades are suggested to contribute to excitatory plasticity in the CNS, including the spinal cord. This study investigated whether the ERK involves in the repetitive stimulation-induced spinal reflex potentiation (SRP) in the pelvic nerve-to-external urethra sphincter reflex activities. External urethra sphincter electromyogram in response to pelvic afferent nerve test stimulation (TS, 1/30 Hz) or repetitive stimulation (RS, 1 Hz) was recorded in anesthetized rats. TS evoked a baseline reflex activity, whereas RS produced SRP in associated with significant ERK 1/2 phosphorylation. RS-induced SRP and ERK 1/2 phosphorylation were both abolished by pretreatment of U0126 (MEK inhibitor). Intrathecal CNQX (AMPA receptor antagonist) attenuated, while AP5 (NMDA receptor antagonist) abolished the RS-induced SRP and ERK 1/2 phosphorylation. Pretreated U0126 abolished the SRP elicited by glutamatergic agonists including glutamate, NMDA and AMPA. Intrathecal H89 and BIS7 (PKA and PKC inhibitors, respectively) both abolished the RS- and glutamate agonist-induced SRP as well as ERK 1/2 phosphorylation. In addition, forskolin and PMA (PKA and PKC activator, respectively) induced SRP, which were both abolished by pretreated U0126. Saline distension, mimicking the storage phase of the urinary bladder, induced SRP and ERK 1/2 phosphorylation. In conclusion, activated ERK 1/2 may produce SRP in the pelvic nerve-to-external urethra sphincter reflex activity, which is essential for urine continence. In addition, blockage of spinal ERK 1/2 activation decreases the physiological function of the urethra, indicating that phosphorylation of the ERK 1/2 cascade may represent a novel target for the treatment of patients with neurological incontinence of spinal origin.     

靶向Pim蛋白激酶抗肿瘤药物的研究进展及设想

Pim原癌基因编码的丝／苏氨酸蛋白激酶在恶性血液病和实体瘤的发生发展过程中普遍过度表达．并被证明在细胞的增殖、分化、新陈代谢中起到重要调控作用。为了弄清Pim蛋白激酶的特性,以指导合成高成药性小分析靶向抑制剂,文章回顾了近年来国外在Pim蛋白激酶领域最新研究成果,着重分析了Pim激酶在分子层面上的功能和作用机制,以及Pim蛋白激酶抑制剂开发的前提条件,包括已获得的Pim蛋白三维晶体结构和Pim基因完整序列,提出了通过基于生物信息学、药理学的靶向小分子药物的设计、合成和筛选,人工合成Pim蛋白激酶抑制剂,研发新型抗肿瘤药物的思路。     

反相离子对HPLC法测定细胞中蛋白激酶活性

建立一种用 ＨＰＬＣ测定细胞中蛋白激酶活性的方法。方法：μＲｏｎｄｏｐｋａ Ｃ１８柱;流动相：甲醇：磷酸盐缓冲液（２０：８０ｖ／ｖ,内含５ ｍｍｏｌ／Ｌ ＰｉＣＡ,ｐＨ ７．０）;检测波长为２５９ ｎｍ;柱温：室温;灵敏度：０．０１ ＡＵＦＳ;进样 ２０ μｌ。结果：酶蛋白用量 ０． ３ ｍｇ左右、反应时间为 １０ ｍｉｎ、Ｈｉｓｔｏｎｅ（ Ⅲ－Ｓ）用量 １ｍｇ／ｍｌ、 ＡＴＰ浓度 ５００ μｍｏｌ／Ｌ时,活性测定结果理想。ＡＴＰ回收率为９９．６３％,ＲＳＤ为１．１１％（ｎ＝６）。结论：该方法简便、准确,适合于蛋白激酶的活性测定。     

蛋白激酶C激活剂和抑制剂对肿瘤坏死因子杀瘤活性的影响

以小鼠成纤维细胞瘤L929细胞为靶细胞,研究蛋白激酶C(PKC)的激活剂和抑制剂对人重组肿瘤坏死因子(rHuTNF)杀瘤活性的影响.各种药物与rHuTNF 10 ng·ml~(-1)和放线菌素D 1 μg·ml~(-1)温育18 h,结果表明PKC的激活剂佛波醇-12-肉豆蔻酸盐-13-乙酸盐(PMA)2.5～160ng·ml~(-1)可浓度依赖性地抑制rHuTNF的杀瘤活性.Sc-10(1～16μg·ml~(-1))单独作用很弱,但可浓度依赖地增强PMA 10 ng·ml~(-1)或A23187 0.5μg·ml~(-1)的抑制作用,PKC抑制剂1-(5-异喹啉磺酰基)-2-甲基哌嗪(H-7)单独作用对rHuTNF杀瘤活性无影响,但可减弱PMA 50ng·ml~(-1)的抑制作用.槲皮囊2～16μg·ml~(-1)则可直接抑制rHuTNF的杀瘤活性,钙调蛋白抑制剂N-(6-氨己基)-5-氯-1-萘磺酰胺(W-7)及其同系物也有微弱的抑制作用.结果提示PKC在rHuTNF杀瘤作用中起着重要作用.