右美托咪定对乳大鼠心肌细胞线粒体活性氧和细胞凋亡的影响

目的:探讨右美托咪定(Dexmedetomidine,DEX)对线粒体介导的乳大鼠心肌细胞氧化应激通路的作用。方法:取新生乳大鼠(3~4天)的心肌进行原代培养,培养24h后分为对照组(C组)、H_2O_2组(终浓度500μM,H组)、右美托咪定组(5μM DEX,D组)、联合用药组(500μM H_2O_2+5μM DEX,DH组)。各组细胞分别给予相应药物刺激6h,采用流式细胞仪测定活性氧自由基(Reactive oxygen species,ROS)水平及心肌细胞凋亡变化;并通过ELISA法测定各组乳大鼠心肌细胞线粒体介导的凋亡因子Caspase-3,Caspase-9表达的变化。结果:与H_2O_2组相比,DEX明显抑制H_2O_2介导的乳大鼠心肌细胞的ROS水平增加(P0.05);下调线粒体介导的下游凋亡因子Caspase-3,Caspase-9的表达(P0.05),从而减少H_2O_2诱导的凋亡(P0.05)。结论:右美托咪定通过抑制心肌细胞活性氧水平以及下调线粒体介导的Caspase-3和Caspase-9的表达发挥抑制凋亡作用,对心肌细胞有一定的保护作用。     

右美托咪定对大鼠脑缺血再灌注损伤后长期的神经保护作用

目的:探讨右美托咪定对大鼠脑缺血再灌注损伤后长期的神经保护作用。方法:采用局灶性脑缺血(MCAO)模型,成年雄性SD大鼠60只,随机将其分为3组(n=20):假手术组(Sham组),缺血再灌注组(I/R组)和缺血再灌注+右美托咪定组(I/R+D组)。I/R+D组大鼠于栓塞前30min腹腔注射右美托咪定100μg/kg。检测右美托咪定对脑梗死容积、半暗带区凋亡神经元数目及神经功能的影响。结果:在大鼠缺血再灌注72 h后,TNF-α和IL-6含量明显降低(P0.05),7 d后Tunel阳性细胞数目显著减少(P0.01)。I/R+D组Garcia评分在3 d、7 d和14 d显著高于I/R组(P0.05)。旷场实验发现,I/R+D组大鼠14 d中央区活动路程显著增加(P0.01)。结论:右美托咪定可减轻大鼠脑缺血再灌注急性期的炎症反应,抑制神经元变性和凋亡,促进大鼠长期的神经功能恢复。     

五味子乙素对链脲佐菌素诱导的糖尿病大鼠视网膜病变的保护作用及机制研究

目的:探究五味子乙素(SB)对链脲佐菌素(STZ)诱导的糖尿病视网膜病变(DR)的作用及作用机制。方法:腹腔注射STZ复制大鼠DR模型,并连续给予SB 9个月,TUNEL检测细胞凋亡,试剂盒检测氧化应激标记分子的含量,ELISA法检测炎症因子的表达,Western blot检测血管新生因子和Cdc42/p38通路蛋白的表达。结果:STZ可明显升高大鼠血糖浓度,表明造模成功; SB可明显减弱STZ对凋亡小体形成的促进作用; SB还能显著促进DR大鼠抗氧化分子SOD的表达,降低氧化产物MDA和LDH的含量;同时,SB可明显缓解STZ对炎症因子(IL-6、TNF-α和IL-1β)分泌的促进作用;此外,SB还能明显减弱STZ对促血管新生因子VEGF和通路蛋白Cdc42和p-p38表达的促进作用。结论:SB可通过Cdc42/p38通路缓解STZ诱导的大鼠DR。     

右美托咪定抗缺血再灌注损伤的信号通路

背景：右旋美托咪定具有抗缺血再灌注损伤的作用,但对其信号通路全面、系统的综述较少。目的：重点对右旋美托咪定在抗氧化应激、抑制炎症、抗凋亡、自噬等机制方面的信号通路进行综述。方法：计算机检索PubMed数据库、中国知网、万方数据库及维普数据库的相关文章,英文检索词为“ischemia-reperfusion injury,dexmedetomidine,signal path,oxidative stress,inflammation,apoptosis”;中文检索词为“缺血再灌注损伤,右旋美托咪定,信号通路,氧化应激,炎症,凋亡”。排除重复性研究及部分相关性较低的基础类文章,最终纳入57篇文献进行评价。结果与结论：(1)右旋美托咪定主要通过抗氧化应激损伤、抗炎、抗细胞凋亡和自噬等多种机制发挥器官保护作用,这其中又涉及众多通路,主要包括Nrf2及其下游蛋白抗氧化应激通路、Toll样受体4家族和核因子κB相关抗炎通路、JAK2/STAT3相关抗炎通路、胆碱能抗炎通路,而且胆碱能通路是众多核因子κB信号通路的上游机制;(2)PI3K/Akt通路依据其激活的下游信号不同发挥不同的作用,抑制NL...     

探究右美托咪定对异丙酚麻醉新生大鼠脑损伤的作用

目的 从丝裂原活化蛋白激酶(MAPK)/细胞外调节蛋白激酶(ERK)信号通路,探究右美托咪定抗异丙酚麻醉所致新生大鼠脑损伤的作用机制。方法 异丙酚麻醉诱导建立新生大鼠脑损伤模型,分为正常对照组、异丙酚组、右美托咪定+异丙酚组、MAPK抑制剂+异丙酚组、右美托咪定+抑制剂+异丙酚组,每组20只。Westernblot法检测MAPK/ERK、PI3K/AKT通路相关蛋白及神经突触素(synapsinI)、生长相关蛋白-43(GAP-43)、神经生长营养因子(BDNF)、突触后致密区蛋白95(PSD95)表达水平。结果 右美托咪定可改善异丙酚反复麻醉的新生大鼠海马组织神经元损伤、凋亡,升高ATP酶活性,降低Ca²⁺水平,促进MAPK/ERK和PI3K/AKT通路活化及与神经生长及发育相关蛋白表达,并改善新生大鼠成年后神经元减少及学习记忆能力降低现象(P<0.05)。MAPK抑制剂干预,可加重异丙酚麻醉的新生大鼠神经元损伤凋亡,并逆转右美托咪定的上述作用(P<0.05)。结论 右美托咪定可通过激活MAPK/ERK活化,来发挥神经保护效应,减轻异丙酚麻醉诱发的神...     

右美托咪定对脑缺血再灌注大鼠海马神经细胞凋亡的影响

目的 探讨右美托咪定对脑缺血再灌注大鼠海马神经细胞凋亡的影响及可能机制.方法 54只雄性SD大鼠随机分为假手术组、模型组和右美托咪定处理组,线栓法制备大鼠大脑缺血再灌注模型.末次给药24h后,检测各组大鼠脑组织含水量、伊文思蓝含量;TUNEL染色检测各组大鼠海马神经细胞凋亡;Western blot方法检测各组大鼠海马...     

京尼平抑制高糖诱导的大鼠心肌H9c2细胞氧化应激及凋亡损伤

目的:探讨京尼平(genipin,GEN)对高糖损伤的大鼠心肌H9c2细胞的抗氧化作用和抑制细胞凋亡的机制。方法:体外培养大鼠心肌H9c2细胞,高浓度(50 mmol/L)葡萄糖处理H9c2细胞建立细胞损伤模型,分为正常糖对照组(NC组,葡萄糖浓度为5.6 mmol/L)、高糖损伤组(HG组,葡萄糖浓度为50 mmol/L)、正常糖+京尼平组(NC+GEN组)和高糖+京尼平组(HG+GEN组,京尼平浓度为10μmol/L)。CCK-8法检测细胞活力;酶标法和WST-1法分别测定细胞内丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;微板法检测细胞培养上清液中乳酸脱氢酶(LDH)活性;荧光探针DCF检测细胞内活性氧簇(ROS)水平;ELISA法检测核小体片段的聚集值;线粒体膜电位检测试剂盒(JC-1)检测细胞内线粒体膜电位变化;利用Western blot法检测线粒体内抗氧化酶锰超氧化物歧化酶(Mn-SOD),以及早期凋亡蛋白细胞色素C(Cyt C)、Bax和cleaved caspase-3的蛋白水平。结果:与HG组比较,HG+GEN组细胞活力显著升高(P 0.05),细胞内MDA的含量及细胞上清液中LDH的活性明显降低(P 0.05),细胞内SOD活性升高(P 0.05),细胞内线粒体膜电位明显升高(P 0.05),ROS水平降低(P 0.05),核小体片段聚集程度显著降低(P 0.05)。HG组线粒体内抗氧化酶Mn-SOD比NC组降低(P 0.05),但线粒体内凋亡蛋白Cyt C、Bax和cleaved caspase-3的蛋白水平比NC组显著升高(P 0.05),而HG+GEN组与HG组相比,Mn-SOD升高(P 0.05),Cyt C、Bax和cleaved caspase-3的蛋白水平显著降低(P 0.05)。结论:京尼平对高糖损伤的心肌H9c2细胞具有抗氧化保护作用和抑制细胞凋亡的作用。     

真武汤对链脲佐菌素所致大鼠糖尿病肾病的保护作用

目的：探讨真武汤对糖尿病大鼠肾脏的保护作用及机制。方法：腹腔注射链脲佐菌素(STZ)建立糖尿病肾病大鼠模型,将成模大鼠随机分为糖尿病肾病(DN)模型组和真武汤治疗组（真武组）,另设正常组。采用生化、HE染色观察真武汤对糖尿病肾病大鼠肾功能、肾组织形态学变化及脂质过氧化相关参数的作用;采用蛋白免疫印迹方法探讨真武汤对肾组织α-平滑肌肌动蛋白（α-SMA）和NF-κB表达的影响。结果：模型组大鼠肾系数、24h尿蛋白定量、血尿素氮、肌酐、血糖和丙二醛(MDA)均显著升高(P<0.05),体重、超氧化物歧化酶(SOD)及诱导型一氧化氮合酶（iNOS）显著降低(P<0.05);真武组大鼠的肾系数、24h尿蛋白、尿素氮、肌酐、血糖和MDA明显低于模型组(P<0.05),iNOS显著高于模型组（P<0.05）;模型组大鼠肾小球肥大、毛细血管基底膜增厚,系膜基质增生,肾小管上皮细胞空泡样变,可见蛋白管型;真武组病变轻于模型组。模型大鼠肾组织α-SMA及NF-κB蛋白的水平明显高于正常组（P<0.05）,真武组大鼠肾组织α-SMA及NF-κB蛋白水平明显低于模型组（P<0.05）。结论：真武汤能减轻糖尿病肾病肾脏局部氧化应激反应,改善糖尿病肾病大鼠肾功能,减轻病理损伤,其发挥肾脏保护作用可能与抑制α-SMA及NF-κB蛋白的表达有关。     

心肌ONOO- 改变对糖尿病大鼠缺血再灌注损伤及细胞凋亡的影响

目的：测定不同周期链脲佐菌素（STZ）诱导糖尿病大鼠心肌超氧亚硝酸根离子(ONOO-)改变及其对缺血/再灌注（I/R）损伤及细胞凋亡的影响。方法：阻断和开放左冠状动脉前降支建立大鼠急性心肌I/R模型,用TTC染色,测定大鼠心肌I/R后梗死面积;用免疫印迹法定量分析代表心肌凋亡水平的半胱氨酸天冬氨酸蛋白酶3（caspase-3）的表达;形态测定（morphometric）法测定ONOO-生成的标志性产物硝基酪氨酸（NT）的水平。结果：在STZ处理后2周糖尿病组(2WKD)心肌梗死面积35.00%±3.00%,明显小于相应周期对照组(2WKC)51.00%±3.30%,P<0.05;STZ处理后16周糖尿病组(16WKD),梗死面积61.00%±3.00%大于相应对照组(16WKC)50.00%±2.00%,P<0.05;在缺血再灌注后,caspase-3的表达,在2WKD+I/R组（A值：481±77）小于2WKC+I/R组（A值：1033±46）,而16WKD+I/R组（A值：1206±78）caspase-3的表达高于16WKC+I/R组（A值：940±72）,P<0.05;硝基酪氨酸的水平在2WKD组（A值：211±13）明显低于2WKC组（A值：409±12）,但在16WKD组（A值：506±37）则高于16WKC组（A值：378±46）,P<0.05。结论：STZ诱导急、慢性期糖尿病对心肌I/R损伤和细胞凋亡的影响呈现相反的作用,这可能是由于急、慢性期糖尿病心肌相反的ONOO-水平而引起的。     

右美托咪定在大鼠脊髓缺血再灌注损伤中的 保护作用及机制研究

目的 探讨右美托咪定对大鼠脊髓缺血/再灌注损伤的保护作用及PI3K/Akt传导通路在其中的作用。方法 30只成年雄性大鼠随机分为假手术组、模型组和右美托咪定治疗组,每组10只。建立大鼠脊髓缺血/再灌注损伤模型,对再灌注损伤后6 h、12 h、24 h、48 h实验大鼠后肢运动功能进行评分,检测缺血脊髓前角组织中P-AKT的表达水平及神经元的凋亡指数。结果 右美托咪定可改善脊髓缺血/再灌注损伤后实验大鼠的后肢运动功能(P＜0.05);提高脊髓前角P-AKT的表达水平(P＜0.05),抑制缺血/再灌注损伤所致的脊髓神经元的凋亡(P＜0.05)。结论 右美托咪定对脊髓缺血/再灌注损伤有一定的保护作用,其机制可能与激活PI3K/Akt传导通路,从而抑制神经元的凋亡有关。     

Astaxanthin inhibits oxidative stress and apoptosis in diabetic retinopathy

BackgroundThe pathophysiology of diabetic retinopathy (DR) is thought to be influenced by oxidative stress. Astaxanthin (ASX) is a natural product with antioxidant effect, but it is not clear whether its mechanism of inhibiting the development of DR is related to anti-oxidation.MethodsRats were intraperitoneally injected with streptozotocin (60 mg/kg) to create DR rat models followed by ASX (20 mg/kg) for 45 days. Retinal tissue was examined by Hematoxylin and Eosin staining. By using Enzyme-linked immunosorbent assay (ELISA), 2,7-Dichlorodrhydrofluorescein diace (DCFH-DA) probes, immunohistochemistry and western blot, it was feasible to evaluate the contents of inflammation-related factors (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and macrophage inhibitory cytokine-1 (MIC-1)), oxidative stress-related indicators (glutathione (GSH), malonic dialdehyde (MDA), glutathione peroxidase (GPx), reactive oxygen species (ROS) and Total antioxidant capacity (T-AOC)), antioxidant enzymes (hemoxgenase-1(HO-1) and Quinone Oxidoreductase 1 (NQO1)), and apoptosis-related proteins (Bcl-2, Bcl2 Associated X Protein (BAX), and cleaved-caspase-3). Additionally, antioxidant proteins downstream of the nuclear factor E2 related factors (Nrf-2) pathway, expression levels of Nrf2/ Kelch-like ECH-associated protein 1(Keap 1) pathway-associated proteins, and nuclear and cytoplasmic levels of Nrf2 were assessed using immunohistochemistry, western blot, or quantitative real-time polymerase chain reaction (qRT-PCR).ResultsASX alleviated retinal tissue damage by increasing overall retina thickness and ganglion cell layer (GCL) cell numbers and exerted the anti-inflammatory, anti-oxidative stress, and anti-apoptosis effects in DR rats. Additionally, ASX could inhibit the expression of Keap1, promote the transport of Nrf2 from cytoplasm to nucleus and facilitate the expressions of HO-1, NQO1, γ-glutamylcysteine synthetase, (γ-GCS) and GPx.ConclusionASX exerted antioxidant effects through Nrf2/keap1 pathway, thereby alleviating apoptosis, inflammation, and oxidative stress in retinal tissues of DR rats.     

Potential antiosteoporosis effect of biodegradable magnesium implanted in STZ-induced diabetic rats

Pure magnesium (Mg) was implanted intramedullary into the femur of streptozotocin (STZ)-induced diabetic rats to investigate its effect on bone growth after 6 weeks degradation. The experimental results showed that the femoral BMD in diabetic rats was significantly lower than that in controls (p < 0.01) but restored notably by Mg implantation. The contents of calcium (Ca), phosphorus (P), Mg, zinc (Zn), potassium (K), strontium (Sr), and sulfur (S) in bone of diabetic group were significantly lower than those in controls but remarkably increased with implantation of Mg. The residual weight calculation showed that 29.41% of Mg was degraded in vivo. The energy dispersive X-ray spectroscopy (EDS) analysis showed that the reaction layer on the surface of the Mg implant mainly consisted of C, Ca, O, P, and Mg. Besides, serum Mg level was significantly decreased in diabetic group compared with the control group but increased by Mg treatment. Also, there were no significant differences in body weight and blood glucose, as well as blood glycosylated hemoglobin (HbAIc%), serum Ca, alanine aminitransperase (ALT), aspartate aminotransferase (AST), uric acid (UA), nonesterified fatty acid (NEFA), cholinesterase (CHE), and creatinine (CR) levels between diabetic and Mg-implanted rats. The study indicated that Mg implant had no obvious toxicity in STZ-induced diabetic rats and may act as a potential agent to treat osteoporosis.     

沉默微小RNA-218表达保护STZ诱导的糖尿病大鼠肾组织

目的:探讨沉默微小RNA-218(microRNA-218,miR-218)表达对链脲佐菌素(streptozotocin,STZ)诱导的糖尿病肾病大鼠肾脏组织的保护作用及其可能机制。方法:采用单次腹腔注射STZ(50 mg/kg)方法制备糖尿病大鼠模型并构建miR-218短发夹RNA(short hairpin RNA,shRNA)慢病毒载体。SD大鼠被随机分为健康对照组、糖尿病模型组、空载慢病毒组及miR-218-shRNA组。于自动生化仪上检测不同时点(4、8和12周)大鼠血糖、24h尿蛋白量、血清肌酐(serum creatinine,SCr)及血尿素氮(blood urea nitrogen,BUN)含量。实时荧光定量PCR(RTqPCR)检测肾脏组织miR-218的表达。RT-qPCR和Western blot检测血红素氧合酶1(heme oxygenase-1,HO-1)、肾病蛋白(nephrin)和p38丝裂原激活的蛋白激酶(p38 mitogen-activated protein kinase,p38 MAPK)的mRNA及蛋白表达水平。Caspase-3活性检测试剂盒检测caspase-3活性。末端脱氧核苷酸转移酶介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling,TUNEL)法检测肾脏组织细胞凋亡。结果:与健康对照组相比,STZ处理后大鼠miR-218表达水平显著升高。同时模型大鼠的血糖、24 h尿蛋白量、SCr及BUN含量显著升高(P0.05);模型大鼠肾脏组织中HO-1和nephrin的mRNA和蛋白表达水平显著降低,而p38 MAPK蛋白的磷酸化水平显著升高;另外,模型大鼠肾脏组织中的caspase-3活性也显著升高。模型大鼠感染miR-218-shRNA后,miR-218表达水平显著下降并可以显著逆转上述效应。miR-218-shRNA组肾脏组织细胞的凋亡水平显著低于糖尿病模型组及空载慢病毒组。结论:miR-218参与了糖尿病大鼠的肾脏损伤,慢病毒载体沉默其表达能有效抑制肾脏组织细胞的凋亡,提示miR-218可以作为糖尿病肾病的基因治疗靶点。     

糖尿病大鼠阴茎的氧化应激与阴茎勃起功能障碍的关系

目的 探讨氧化应激在糖尿病性阴茎勃起功能障碍（ED）中的作用。 方法 注射链脲佐菌素建立糖尿病大鼠模型,分别在注射8周和12周后观察阴茎勃起次数;取大鼠阴茎,测定阴茎丙二醛水平、总抗氧化能力,免疫印迹法检测阴茎核因子E2相关因子2(Nrf2)蛋白量的变化。 结果 糖尿病大鼠的阴茎勃起次数明显低于对照组,并随病程延长降低;糖尿病大鼠阴茎丙二醛水平明显高于对照组,总抗氧化能力水平明显低于对照组;与对照组比较,糖尿病组大鼠阴茎内Nrf2蛋白量随病程延长而降低。 结论 糖尿病性阴茎勃起功能障碍与阴茎氧化应激水平升高相关。     

糖尿病大鼠心肌TGF-β1表达及细胞凋亡的实验研究

目的:研究糖尿病大鼠心肌转化生长因子β1(TGF-β₁)表达水平和细胞凋亡的变化，探讨糖尿病性心肌病的病理生理机制。方法：链脲菌素法复制不同病程的糖尿病模型。免疫组化方法测定TGF-β₁的表达。DNA断端末端标记法测定心肌细胞凋亡指数。结果：糖尿病大鼠心肌细胞TGF-β₁表达明显高于正常对照组（P<0.01）。TUNEL法测定心肌细胞的凋亡阳性细胞数量在糖尿病早期明显高于正常，晚期有所减少。结论：TGF-β₁在糖尿病的心肌中表达增加，且随病程发展而上升，可能是糖尿病心肌纤维化的重要促发因子。糖尿病心肌中细胞凋亡现象随病程延长而逐渐减弱，机制有待探讨。     

Protective effect of lycopene against ochratoxin A induced renal oxidative stress and apoptosis in rats

This study was designed to investigate the possible protective effect of lycopene against the renal toxic effects of OTA. Male Sprague-Dawley rats (<200 g, n = 6) were treated with OTA (0.5 mg/kg/day) and/or lycopene (5 mg/kg/day) by gavage for 14 days. Histopathological examinations were performed and apoptotic cell death in both cortex and medulla was evaluated by TUNEL assay. Besides, biochemical parameters and activities of renal antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD); concentrations of total glutathione (GSH), and malondialdehyde (MDA) levels were measured. OTA treatment was found to induce oxidative stress in rat kidney, as evidenced by marked decreases in CAT (35%) activity and GSH levels (44%) as well as increase in SOD activity (22%) vs control group. Furthermore, TUNEL analysis revealed a significant increase in the number of TUNEL-positive cells in cortex (49%) and medulla (75%) in OTA administrated group compared to control (p < 0.05). Lycopene supplementation with OTA increased GPx1 activity and GSH levels, and decreased apoptotic cell death in both cortex and medulla vs. control. The results of this study showed that at least one of the mechanisms underlying the renal toxicity of OTA is oxidative stress and apoptosis is the major form of cell death caused by OTA. Besides, our data indicate that the natural antioxidant lycopene might be partially protective against OTA-induced nephrotoxicity and oxidative stress in rat.     

Protective effect of the daming capsule on impaired baroreflexes in STZ-induced diabetic rats with hyperlipoidemia

Background  

The Daming capsule (DMC) is a traditional Chinese medicine used to treat hyperlipoidemia. Both clinic trials and studies on animal models have demonstrated that DMC is beneficial against diabetic symptoms. Impairment of the baroreflex can cause life-threatening arrhythmias and sudden cardiac death in patients with diabetes mellitus (DM). This study was designed to elucidate the effects of DMC on baroreflexes in streptozocin (STZ)-induced diabetic rats with hyperlipoidemia.     

Effect of magnesium supplementation on oxidative stress in alloxanic diabetic rats.

Magnesium deficit and oxidative stress are common features of the diabetic state. This concept supported by another observation that magnesium deficiency is also a state of increased oxidative stress prompted us to study the effect of magnesium supplementation on magnesium status and oxidative stress in diabetic rats. For this purpose, male Wistar rats were made diabetic with a single intraperitoneal injection of Alloxan. Experimental diabetes caused a significant decrease in serum and red blood cell magnesium levels and increased urinary excretion of magnesium. Marked increase in plasma malondialdehyde and corresponding decrease in vitamins C & E, uric acid and total thiols was observed in the diabetic rats as compared to control group. In liver, MDA levels were increased significantly with concomitant decrease in vitamin C, non-protein thiols and antioxidant enzymes (SOD & GST). Magnesium supplementation for four weeks restored serum and RBC magnesium levels to near normal levels with marginal but significant decrease in blood glucose levels. Plasma and liver MDA levels were reduced significantly and vitamin C and total thiols were increased significantly with magnesium supplementation. Antioxidant enzyme activity was also increased significantly with magnesium supplementation in diabetic rats. Our data clearly demonstrates that alloxanic diabetes is associated with decreased magnesium status and increased oxidative stress and that magnesium supplementation can in part restore the antioxidant parameters and decrease the oxidative stress in experimental diabetic rats.     

Abnormal feeding behavior and insulin replacement in STZ-induced diabetic rats

The present studies were undertaken to investigate whether or not decreased ambulatory activity, including abnormal feeding behavior in diabetic rats, will be simultaneously normalized by insulin administration. To do this, we used the Gunma University-type automatic apparatus for continuous and direct measurement of ambulation and drinking. In this study, 3 U NPH insulin were administered at 1800, just before the dark phase, and 2 U were administered at 0600, just before the light phase. With these insulin doses, we found that 5 weeks were needed to normalize ambulatory activity, 4 weeks were necessary for food intake, 6 weeks for drinking and 2 weeks for body weight. Since ambulatory activity is reported to be related to changes in dopamine turnover, further studies are in progress to determine whether or not dopamine turnover is normalized when there is no difference in ambulatory activity due to insulin replacement.     

硫化氢供体对阿霉素心肌病大鼠氧化应激作用的影响

目的： 探讨外源性给予硫化氢供体硫氢化钠(NaHS)对阿霉素(adriamycin, ADR)心肌病大鼠氧化应激作用的影响。方法：雄性Wistar大鼠54只，随机分为5组：(1) ADR组(n=12)：腹腔注射ADR，每次2.5 mg/kg，每周1次，共用药10周；(2)ADR+小剂量NaHS组（n=12）：ADR用药方法同ADR组，同时经腹腔注射NaHS，2.8 μmol·kg-1·d-1，连续用药10周；(3)ADR+大剂量NaHS组（n=12）：ADR用药方法同ADR组，同时经腹腔注射NaHS，14 μmol·kg-1·d-1，连续用药10周；(4)对照组（n=9）：用相同容量的生理盐水代替ADR，给药方法同ADR组；(5)NaHS组（n=9）：经腹腔注射NaHS，14 μmol·kg-1·d-1，连续用药10周。于第10周检测大鼠心功能和血流动力学指标,并测定其血清及心肌组织中H2S、脂质过氧化物丙二醛(MDA) 的含量以及超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活性，比较其中的差异。结果：ADR组大鼠心功能较对照组明显降低(均P<0.01)，且血清及心肌组织H2S含量均明显低于对照组(P<0.01），MDA含量明显较对照组升高(均P<0.01)，SOD的活性明显降低(均P<0.01)，GSH-Px的活性亦明显降低(血清及心肌组织：P<0.05，P<0.01)；经外源性补充H2S供体NaHS后，大鼠心功能较前明显改善，ADR+大剂量NaHS组心肌组织中过氧化产物MDA含量明显降低(均P<0.01)，而血清MDA含量无明显差异(P>0.05)；ADR+大剂量NaHS组血清SOD活性明显升高(P<0.01)，而心肌组织SOD活性无明显差异(P>0.05)；ADR+大剂量NaHS组心肌组织GSH-Px活性明显增高(均P<0.05)，而血清GSH-Px活性无明显差异(P>0.05)。结论：硫化氢参与了大鼠阿霉素心肌病的发病过程,外源性补充硫化氢供体NaHS可以改善阿霉素心肌病大鼠心功能，降低心肌组织中脂质过氧化物的含量，显著提高抗氧化酶体系的活性，减轻氧化应激损伤，从而参与对大鼠心肌的保护机制。