链脲佐菌素制备糖尿病大鼠模型探讨

目的探讨链脲佐菌素(STZ)配合不同饮食建立糖尿病模型的方法,并对模型大鼠学习记忆能力进行考察,为糖尿病的深入研究及药物开发提供可靠的模型。方法雄性SD大鼠70只,随机分为7组,分别为空白对照组(Ⅰ);高糖高脂膳食组(Ⅱ);0周STZ(30 mg/kg)+高糖高脂膳食组(Ⅲ);0周STZ(30 mg/kg)+常规膳食组(Ⅳ);6周STZ(20 mg/kg)+高糖高脂膳食组(Ⅴ);6周STZ(25 mg/kg)+高糖高脂膳食组(Ⅵ);6周STZ(30 mg/kg)+高糖高脂膳食组(Ⅶ)。采用尾静脉注射STZ配合不同饮食制备糖尿病模型,动态监测模型大鼠血糖的变化,生化方法检测大鼠血脂的改变,放免法检测模型大鼠血清胰岛素、胰高血糖素。Morris水迷宫检测不同造模型条件对大鼠空间学习记忆能力的影响。结果与对照组比较,Ⅲ组大鼠于注射72 h后血糖升高明显(P<0.01),至注射第2周血糖升高达顶点(P<0.01),以后逐渐降低,至观察第10周,血糖维持在15 mmol/L(P<0.05)。IV组大鼠于注射72 h后血糖升高,以后迅速降低,至观察第10周,血糖降低至正常水平。Ⅴ、Ⅵ、Ⅶ组大鼠于注射72 h后显著升高,此后呈波浪式变化;随着注射剂量增加,降低程度减慢。高糖高脂饲料喂养10周后,各组大鼠CHO,TG,LDL-C均增加;Ⅲ、Ⅳ、Ⅴ组大鼠血清INS水平较对照组增高,除IV外,各组胰高血糖素均高于对照组。水迷宫试验结果显示,Ⅶ组潜伏期延长,与对照组比较,具有统计学意义。结论 STZ(30 mg/kg)配合高糖高脂膳食能够快速、稳定的建立糖尿病大鼠模型,高糖高脂膳食组6周后尾静脉注射STZ(30 mg/kg)制备模型,血糖升高显著,血清胰岛素水平降低明显,倾向于1型糖尿病模型。     

不同剂量链尿佐菌素诱导2型糖尿病大鼠模型的研究

目的:探讨不同剂量链脲佐菌素(Streptozotocin,STZ)联合高糖高脂饮食对2型糖尿病大鼠模型建立的影响。方法:90只8周龄SD雄性大鼠随机平均分为六组:普通饲料喂养+缓冲液组、高糖高脂饲料喂养+缓冲液(H.E组)、高糖高脂饲料喂养+35mg/kg链尿佐菌素组(H.E+35 mg/kg STZ组)、高糖高脂饲料喂养+45 mg/kg链尿佐菌素组(H.E+45 mg/kg STZ组)、高糖高脂饲料喂养+55 mg/kg链尿佐菌素组(H.E+55 mg/kg STZ组)及高糖高脂饲料喂养+65 mg/kg链尿佐菌素组(H.E+65 mg/kg STZ组),高糖高脂饲料喂养4周后诱导胰岛素抵抗,继之腹腔注射STZ,建立2型糖尿病大鼠模型。检测体重、胰岛素、空腹血糖、血脂、胰岛素敏感指数(ISI)。结果:与常规饮食组相比,高糖高脂饮食各组大鼠出现空腹血浆胰岛素(FINS)、空腹血糖(FBG)、血清甘油三脂(TG)、总胆固醇(TC)、游离脂肪酸(FFA)显著升高(P0.01),ISI显著下降(P0.01)。不同剂量STZ注射,H.E+45 mg/kg STZ组成模率最高且无自愈现象。结论:通过STZ腹腔注射联合高糖高脂饮食可成功复制出实验性2型糖尿病动物模型,45 mg/kg为STZ理想注射剂量。     

2型糖尿病大鼠模型制备的影响因素及其特点

目的探讨高脂喂养联合低剂量链脲佐菌素(Streptozotocin,STZ)制备2型糖尿病大鼠模型的造模方法和影响因素。方法4周龄雄性Sprague Dawley(SD)大鼠45只随机分为三组:(1)正常组(normal control,NC),9只,普通饲料喂养。(2)高脂组(high fat,HF),9只,高脂饲料喂养。(3)糖尿病模型组,根据高脂喂养时间差异和STZ剂量不同设计了3种模型制备方法:A组,9只,高脂喂养满4周,注射STZ 30 mg/kg;B组,9只,高脂喂养满8周,注射STZ 20 mg/kg;C组,9只,高脂喂养满8周,注射STZ 30 mg/kg。所有大鼠于48h、2周和4周后行灌胃葡萄糖耐量试验(OGTT)评价成模率和血糖波动情况。实验结束时测定血清胰岛素、甘油三酯(TG)和胆固醇(TC),RT-PCR测定胰腺内胰岛素mRNA表达水平,免疫组化染色观察胰岛细胞形态学特点,用彩色图像分析系统进行定量比较。结果糖尿病C组血糖显著升高,成模后2周血糖下降,4周后又上升到基线水平,成模率100%。糖尿病A组、B组在4周后血糖逐渐降低到接近正常水平,成模率分别为55.6%、11.1%。C组与HF组相比,胰岛素敏感性显著下降(P<0.01)。β细胞内胰岛素水平下降39.3%(P<0.01),胰岛内β细胞所占比例下降了79.2%(P<0.01),胰腺内胰岛素mRNA表达水平减少19.2%(P<0.01),α细胞升高了1倍(P<0.01)。结论高脂喂养8周后腹腔注射低剂量STZ(30 mg/kg)制备的2型糖尿病大鼠模型,成模率高,模型稳定。     

玉米胚SOD提取物对糖尿病大鼠血糖、血脂及血清氧化应激状态的影响

目的:探讨玉米胚SOD提取物对于糖尿病大鼠血糖及主要脏器抗氧化能力的影响.方法:成年雄性Wistar大鼠36只,随机分为以下6组:1)正常对照组;2)糖尿病模型组:腹腔注射四氧嘧啶175mg/kg,连续两天;3)二甲基双胍对照组:糖尿病模型+灌服10mg/kg盐酸二甲基双胍;4)SOD高剂量组:糖尿病模型+灌服0.3gSOD提取物;5)SOD中剂量组:糖尿病模型+灌服0.18g SOD提取物;6)SOD低剂量组:糖尿病模型+灌服0.06g SOD提取物.连续3周,动态监测血糖,血清总胆固醇和甘油三酯.45天后处死动物,提取血清,采用硫代巴比妥酸法测定脂质过氧化产物丙二醛(MDA)含量;DTNB法测定还原型谷胱甘肽(GSH)含量;黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活力.结果:不同剂量的玉米胚SOD提取物对四氧嘧啶所致高血糖模型大鼠具有明显的降低血糖作用,可降低血清中总胆固醇和甘油三酯.并使血清MDA水平降低,抗氧化物质GSH含量增加,SOD活力升高.结论:玉米胚SOD提取物具有一定的降低血糖、血脂功效,可能与增加机体抗氧化能力有关.     

改善Ⅱ型糖尿病大鼠糖代谢运动模型的建立

目的建立运动改善Ⅱ型糖尿病大鼠糖代谢模型,为Ⅱ型糖尿病运动处方的建立提供理论参考。方法 SPF级雄性8周龄Wistar大鼠45只,随机抽取32只在高糖高脂饲料喂养7周的基础上腹腔注射小剂量链脲佐菌素(STZ)缓冲液,建立Ⅱ型糖尿病大鼠模型。将正常大鼠和造模成功的大鼠分为4组:空白对照组(C组)、单纯运动组(CE组)、糖尿病对照组(DM组)、糖尿病运动组(DME组)。运动组采用改进的Ploug训练方案,60min/d,每周训练6 d,共训练8周。分别在高脂饲料喂养7周后尾静脉取血测定空腹血糖和血清胰岛素,造模后基线时间和运动8周末尾静脉取血测定空腹血糖(FBG),运动8周末眶后取血测定血清胰岛素(FINS),并计算胰岛素抵抗指数(HOMA-IR)。结果 (1)7周高糖高脂喂养后,与正常组相比,高脂组FBG、FINS和HOMA-IR含量显著升高。(2)8周运动干预后,DM组和DME组FINS水平显著低于C组和CE组,FBG和HOMA-IR显著高于C组和CE组;DME组FINS水平显著高于DM组,FBG和HOMA-IR显著低于DM组。DM组和DME组体重显著低于C组和CE组;DME组与DM组、CE组与C组组间体重差异无显著性。结论 (1)7周高糖高脂喂养联合一次性腹腔注射STZ(30 mg/kg)成功建立Ⅱ型糖尿病大鼠模型;(2)60 min/d共8周的游泳运动模式能够改善Ⅱ型糖尿病大鼠糖代谢,是研究运动锻炼预防和改善糖尿病机理的理想动物模型。     

高脂喂养合并小剂量链脲佐菌素建立2型糖尿病大鼠模型

目的 观察不同配方的高脂饲料,以及不同周龄的大鼠对于该模型的造模成功率和模型病变特点的影响.方法 将26只3周龄SD大鼠分为正常一组(N1组)、模型一组(M1组)和模型二组(M2组);26只5周龄SD大鼠分为正常二组(N2组)、模型三组(M3组)和模型四组(M4组).M1组和M3组给予高脂饲料配方一喂养,M2组和M4组给予高脂饲料配方二喂养.4周后,各模型组大鼠腹腔注射STZ溶液35 mg/kg.连续观察大鼠的空腹血糖(FBG)、空腹胰岛素(FIN)、总胆固醇(TG)、甘油三酯(TC)水平.结果 5周龄SD大鼠的FBG水平在注射STZ后两周即可达到稳定状态,并维持在较高的水平;高脂饲料配方二使大鼠的进食量和体重增加明显,并且成功诱导出胰岛素抵抗( insulin resistance,IR).结论 选取5周龄SD大鼠作为模型动物,并给予配方二高脂饲料喂养,所建立的大鼠模型具备2型糖尿病的主要特征,是值得推广的2型糖尿病动物模型.     

2型糖尿病伴发高血压大鼠模型的建立

目的：建立一种2型糖尿病伴发高血压大鼠的模型。方法：65只SD雄性大鼠,随机分为正常对照组、1% NaCl饮水组、20 mg/kg STZ-1% NaCl组、30 mg/kg STZ-1% NaCl组、40 mg/kg STZ-1% NaCl组（n=13）。除正常对照组大鼠普通饮食喂养外,其余各组大鼠以高脂饲料4周+普通饲料结合1% NaCl饮水9周喂养。第4周末链脲霉素（STZ）组大鼠分别腹腔注射STZ （20 mg/kg、30 mg/kg、40 mg/kg）。实验周期13周。检测大鼠一般状况、体重、平均摄食量、血糖、血压、血脂和血浆胰岛素水平。结果：与正常对照组和1% NaCl饮水组比较,在STZ注射后仅30 mg/kg STZ-1% NaCl组、40 mg/kg STZ-1% NaCl组大鼠体重减少（P<0.05）、平均食量、空腹和随机血糖均增加（P<0.05）;第4周起血压显著升高（P<0.05）,收缩压均值达到150 mmHg进入高血压期,并在其后5周（实验结束前）稳定于150~170 mmHg;第9周血浆胰岛素水平升高（P<0.05）,血浆甘油三酯（TG）水平下降（P<0.05）。结论：高脂饲料喂养4周+腹腔注射STZ 30~40 mg/kg结合1% NaCl饮水喂养,能诱导出2型糖尿病伴发高血压的大鼠模型。     

Gfat1基因在2型糖尿病大鼠肺组织中的表达

观察2型糖尿病大鼠不同时期肺组织谷氨酰胺果糖转移酶1(Gfat1)的表达情况.方法 SD大鼠随机分为正常对照组和模型组,对照组18只,模型组28只.模型组高脂饲料喂养2个月后,腹腔注射链脲佐菌素(STZ 15mg/kg)复制糖尿病模型,统计体重变化及空腹血糖值.RT-PCR方法检测造模成功后2周、4周和6周肺组织Gfat1 mRNA表达.结果 模型组大鼠体重增长较快,造模开始第28天,第42天,第56天和第70天高脂模型组与对照组体重差异有显著性(P＜0.05).注射STZ的高脂模型组空腹血糖值较高(FBG≥10.0),和对照组比较,FBG差异有极显著性(P＜0.01).糖尿病大鼠造模成功后2周,模型组肺组织Gfat1的表达低于对照组,与对照组比较差异无显著性(P＞0.05),4周模型组Gfat1的表达高于对照组,模型组与对照组比较差异有显著性(P＜0.05).6周模型组Gfat1的表达高于对照组,但模型组与对照组比较差异无显著性(P＞0.05).结论 大鼠饲喂高脂饲料结合腹腔注射STZ可成功建立2型糖尿病大鼠模型;在不同时期2型糖尿病大鼠肺组织中,Gfat1表达水平发生改变.     

明日叶查尔酮对2型糖尿病大鼠红细胞胰岛素受体亲和力的影响

目的:研究明日叶查尔酮对2型糖尿病大鼠红细胞胰岛素受体亲和力的影响.方法:将高脂喂养加链脲佐菌素注射诱发的2型糖尿病大鼠随机分为4组,每组10只.糖尿病对照组和高、中、低剂量组喂饲高脂饲料分别经口灌胃明日叶查尔酮0、30、10、5mg (kg·bw)-1,正常对照组为正常大鼠喂饲普通饲料,连续4周.测定空腹血糖、血清胰岛素与MDA、红细胞胰岛素受体结合常数与结合容量等指标.结果:高剂量组的高亲和力与低亲和力胰岛素受体结合常数高于糖尿病对照组,血糖、胰岛素和MDA含量则降低,差异均有显著性(P＜0.05).结论:明日叶查尔酮能提高2型糖尿病大鼠红细胞胰岛素受体亲和力,改善胰岛素抵抗.     

明日叶查尔酮对2型糖尿病大鼠骨骼肌细胞胰岛素抵抗的干预作用

目的:研究明日叶查尔酮对2型糖尿病大鼠骨骼肌胰岛素抵抗的干预作用.方法:将2型糖尿病大鼠随机分成四组,高、中、低剂量组分别每日经口灌胃给予明日叶查尔酮30、10和5mg/(kg·bw),糖尿病对照组给予等量生理盐水.各组均以高脂饲料喂养.四周后采用葡萄糖氧化酶法检测空腹血糖;放射免疫法检测血清胰岛素含量;免疫组化法检测葡萄糖转运体1和葡萄糖转运体4蛋白表达水平.结果:经图像分析,高剂量组骨骼肌细胞中葡萄糖转运体1和葡萄糖转运体4蛋白表达平均光密度值分别为0.054± 0.0064和0.063±0.0139,均较糖尿病对照组显著性升高(P＜0.05).高剂量组空腹血糖和胰岛素水平分别为(12.3± 1.64)mmol/L和(25.65±3.34) (μIU/mL),均较糖尿病对照病显著性降低(P＜0.05).结论:明日叶查尔酮可增加2型糖尿病大鼠骨骼肌葡萄糖转运体l和葡萄糖转运体4蛋白表达水平,降低空腹血糖和胰岛素水平,改善胰岛素抵抗状况.     

Effects of frequent multiple plateletpheresis on complete blood count values of blood donors

The use of apheresis technique to collect platelets has rapidly increased in recent years. With an increased demand for plateletpheresis, higher donation frequencies are now observed. The aim of this study is to investigate changes in complete blood count values after frequent multiple plateletpheresis. A total of seventy-four blood donors were selected, from which complete blood count values in the first and the last screening were taken. There were fifty-four high frequency donors(13.0±2.6 plateletpheresis/year) and twenty low frequency donors(6.6±0.5 plateletpheresis/year). The results showed that complete blood count values at the first and last screening after plateletpheresis of both groups were within the normal range, and changes in their WBC, RBC and PLT values were not statistically significant(P>0.05, P>0.05, and P>0.05, respectively). The study suggests that frequent multiple plateletpheresis has no effects on complete blood count, and no adverse effects on blood donors.     

Hydrolysis of sphingomyelin and phosphatidylcholine by midgut homogenates of the stable fly

Qualitative and quantitative analyses were made to characterize the enzymatic degradation of sphingomyelin and phosphatidylcholine by midgut homogenates of the adult stable fly, Stomoxys calcitrans (L.). The results indicated that sphingomyelin was hydrolyzed by an enzyme with sphingomyelinase-like properties, and that phosphatidylcholine was hydrolyzed by an enzyme with properties similar to phospholipase C. The optimum pH for the sphingomyelinase was 7.6, and the rate of hydrolysis of sphingomyelin at that pH was linear from 1 to 4 nmol of substrate and 5 to 25 micrograms of enzyme preparation. Dialysis of the homogenates against Tris-HCl and imidazole buffers resulted in a decrease of sphingomyelinase activity by 59% and 98%, respectively, and the original activity was not restored with the addition of Ca++, Mg++, or Mn++.     

临床标本采集量对凝血系统检测结果的影响

目的：探讨临床标本采血量的准确性对凝血酶原时间（PT）、活化部分凝血活酶时间（APTT）测定的影响。方法：用BE-RockRotor全自动血凝仪和配套试剂分别对15例临床患者不同抽血量标本进行检测,观察不同的采血量对PT、APTT检测结果的影响,并将所得检测结果采用统计方法处理。结果：与标准采血量为1．8mL相比,采血量大于或小于1．8mL时测得的PTT、APTT结果有显著性差异。结论：临床标本采集量对凝血系统检测结果的准确性有直接影响;必须严格按照标准采血量规定采集标本,才能确保凝血系统检测结果的准确,为病人疾病的诊断提供可靠的实验室依据。     

Time-dependent spatial specificity of high-resolution fMRI: insights into mesoscopic neurovascular coupling

High-resolution functional magnetic resonance imaging (fMRI) is becoming increasingly popular because of the growing availability of ultra-high magnetic fields which are capable of improving sensitivity and spatial resolution. However, it is debatable whether increased spatial resolutions for haemodynamic-based techniques, like fMRI, can accurately detect the true location of neuronal activity. We have addressed this issue in functional columns and layers of animals with haemoglobin-based optical imaging and different fMRI contrasts, such as blood oxygenation level-dependent, cerebral blood flow and cerebral blood volume fMRI. In this review, we describe empirical evidence primarily from our own studies on how well these fMRI signals are spatially specific to the neuronally active site and discuss insights into neurovascular coupling at the mesoscale.This article is part of the theme issue ‘Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity’.     

Frequencies of ABO, Rh and Kell phenotypes in couples from Han, Kazak, Uyghur and Hui in Xinjiang: an inheritance simulation model for blood group incompatibility in new-born

The Xinjiang region with residents from more than 13 minorities represents an area of many diverse ethnicities. This ethnic diversity in relation to their blood groups and immune status may have a consequential impact on the clinical status of married couples. To evaluate the risks of haemolytic disease in new-born infants, we investigated the rate of blood-group incompatibility among 487 married couples from four ethnic minorities, namely the Han, Hui, Uyghur and Kazak populations. Han minority married couples showed significantly different ABO, Rh and K phenotype frequencies between marrial relationship, whereas there was no significant difference in ABO, Rh and K phenotypes between the Uyghur, Hui and Kazak .There was a significant difference between ABO blood types in Han married couples, in the Kazak Rh-C phenotype and in the Uyghur Rh-D phenotype. The Hui married couples only demonstrated ABO, Rh and K phenotypes. The Hui minority showed the highest incompatibility rate for Rh-C and Rh-E phenotypes between mothers and their new-born infants. The highest incompatibility rate for the ABO phenotype occurred in the Kazak group. These results particularly demonstrate the clinical issues relating to ABO and Rh incompatibility, in the Kazak and Hui minorities, respectively.     

Testosterone and Regional Fat Distribution

The effects of testosterone treatment of abdominally obese men have been assessed by evaluating the following parameters: The metabolic activity of different adipose tissue regions in vivo (using lipid label as a tracer) and in vitro (measuring lipoprotein lipase(LPL) activity), the total and visceral adipose tissue mass, insulin sensitivity, fasting blood glucose, blood lipids, and blood pressure as well as prostate volume. Middle-aged men with abdominal obesity were treated with transdermal administration of testosterone (T), dihydrotestosterone (DHT) or placebo (P) during 9 months. The study was double-blind. Treatment with T was followed by an inhibited uptake of lipid label in adipose tissue triglycerides, a decreased LPL-activity and an increased turn-over rate of lipid label in the abdominal adipose tissue region in comparisons with the DHT and P groups. These effects on adipose tissue metabolism were not detected in the femoral adipose tissue region in any of the groups. T treatment was also followed by a specific decrease of visceral fat mass (measured by CT-scan), by increased insulin sensitivity (measured with the euglycemic glucose clamp), by a decrease in fasting blood glucose, plasma cholesterol and triglycerides as well as a decrease in diastolic blood pressure. In the DHT group an increased visceral mass was detected. No other changes in these variables were found in the DHT and P groups. There were no detectable changes in prostate volume (measured by ultra-sound), prostate specific antigen concentration, genito-urinary history or urinary flow measurements in any of the groups. It is suggested that T substitution to a selected group of men results in general metabolic and circulatory improvements. The prostate area needs further careful attention.     

不同采血途径对SSD大鼠全血细胞计数的影响

为探讨不同采血途径对SD大鼠全血细胞计数的影响,采用全自动血液分析对46例正常SD大鼠的全血细胞计数(CBC)进行分析包括WBC、RBC、Hb、HCT、MCV、MCH、MCHC、PLT等指标;分别从尾静脉、眼眶静脉、颈动脉和腹主动脉取血,并以腹主动脉测值为参照进行配对t检验。结果显示:分别比较腹主动脉采血组与尾静脉采血组和眼眶静脉采血组,CBC值除MCV外其他值差异均有统计学意义(P<0.05);腹主动脉采血组和颈动脉采血组两者仅WBC差异有统计学意义(P<0.05)。以上结果说明不同采血途径对SD大鼠全血细胞计数有不同程度的影响,各实验室应建立各自的背景数据,以便能在统一条件下比对。     

Concentrations of heavy metals in maternal and umbilical cord blood

Concentrations of lead, cadmium, methylmercury and total mercury were measured in maternal and umbilical cord blood using graphite atomic absorption spectrometry. Two essential metals, copper and zinc, were also determined using ion chromatography. Lead, copper and zinc were found to be lower in the cord blood, whereas methylmercury and total mercury were higher in cord blood than in maternal blood. Little differences were noted for cadmium in maternal and cord blood. Significant positive correlations were observed between the concentrations in maternal and cord blood with regard to lead (correlation coefficient, r = 0.44), copper (r = 0.34), zinc (r = 0.29), methylmercury (r = 0.44) and total mercury (r = 0.58). These results suggest that, like essential metals, most heavy metals can move rather freely across the human placenta. The potential health effects of heavy metal transfer from mothers to young infants cannot be discounted.     

Action of sauvagine on the mesenteric vascular bed of the dog

Sauvagine, a linear peptide of 40 amino acids, produced hypotension when administered intravenously to anesthetized dogs. Diastolic pressure was always more affected than systolic pressure. Aortic blood flow and venous return both increased to the same extent. The mechanism of the hypotensive response was mainly, if not exclusively, due to dilatation of the superior and inferior mesenteric arteries. Intravenous infusion of sauvagine in doses ranging from 3 to 10 ng · kg^?1 · min^?1 produced a dose-related increased of mesenteric blood flow up to 400% control values. Mucosal-submucosal blood flow of ileum and colon was increased, while blood flow in muscle was unaffected or slight decreased. The mesenteric vasodilator response was not prevented by adrenergic or muscarinic receptor blockade. The hypotensive response was more marked and sustained in dibenamine-propranolol treated dogs.     

我国山药类药材对动物降血糖和降血脂的作用

我国山药类药材对动物降血糖和降血脂的作用杭悦宇（江苏省植物研究所,中国科学院植物研究所,南京２１００１４）ｐｈａｒｍａｃｏｌｏｇｉｃａｌｅｘｐｅｒｉｍｅｎｔｓｏｎｌｏｗｉｎｇｔｈｅｂｌｏｏｄｓｕｇａｒａｎｄｂｌｏｏｄｌｉｐｉｄｓｌｅｖｅｌｏｆＲｈｉｚ...