胡杨悬浮细胞的生长及液泡膜微囊的制备

改进了胡杨细胞悬浮培养体系，细胞得率提高了3倍多。做出了胡杨悬浮细胞：的生长曲线，以培养12～15d为宜。摸索了胡杨细胞破壁技术，使用了研磨、超声、捣碎、French Press法。从蛋白产率、v．H^ ATPaSe活力、反应潜势三个方面考虑选用捣碎法，结合差速离心和蔗糖密度梯度分离纯化液泡膜微囊，完善了从胡杨细胞分离纯化液泡膜微囊的试验流程，从而使液泡膜H^ ATPase的研究成为可能。     

Changes of BAEP,NO contents and Na+-K+ATPase activities in brain tissues in rats with hyperbilirubinemia

AIM: To explore the roles of brain-stem auditory evoked potential (BAEP) in early monitoring the hearing loss and brain damages in hyperbilirubinemia and nitric oxide(NO) in the pathogenesis of bilirubin-induced hearing loss and brain damages. METHODS: Different doses of bilirubin solution (30 mg/kg, 60 mg/kg, 90 mg/kg, 120 mg/kg and 150 mg/kg) were injected into the abdominal cavity of 15-day old SD rats to make the animal model of hyperbilirubinemia. The serum concentrations of bilirubin were detected by a micro-gauge. The bilirubin concentrations in the brain tissues were examined via a diazo method. The Na+-K+ATPase activities in the brain tissues were analyzed by rooting phosphorus. The NO contents in the brain tissues were assayed via the method of nitrate reductase. BAEP were recorded with an evoked potential recorder. RESULTS: After making the ejection, parts of the rats in the high dosage groups (120 mg/kg and 150 mg/kg) showed the abnormal neuro-behaviors. After 6 hours of the ejection, the bilirubin concentrations in serum and in brain tissues, and NO contents in the brain tissues were increased significantly. The Na+-K+ATPase activities in the brain tissues were decreased obviously, and the PL and IPL of BAEP were prolonged significantly in all the experimental rats except the ones in low dosage group (30 mg/kg). The changes of them were closely related to the dose of injected bilirubin. CONCLUSION: The PL and IPL of BAEP are the objective and sensitive indexes for early monitoring the hearing loss and brain damages in hyperbilirubinemia. NO may plays a certain role in the pathogenesis of bilirubin induced hearing loss and brain damages.     

Characterization of myofibrillar adenosine triphosphatase activity and liberation of actin from myofibrils upon heating chicken breast meat

Denaturation of actin and myosin in myofibrils induced by heating at 50°C was investigated to reveal the mechanism of irreversible liberation of actin from myofibrils on heating at lower temperatures than conventional cooking. Denaturation of these proteins was determined by Mg²⁺‐ATPase (adenosine triphosphatase) and Ca²⁺‐ATPase activities. When minced meat was heated for 20 min, actin was liberated accompanying denaturation of 80% of actin and 50% of myosin. Heating of the myofibrillar fraction (MFF) isolated from meat homogenate induced much slower denaturation of actin than myosin. When MFF was heated with sarcoplasmic fractions, denaturation of actin was facilitated, suggesting that sarcoplasmic fractions contain factors to facilitate actin denaturation. Inosine‐5′‐monophosphate, a component of sarcoplasmic fractions, was shown to have no effect on actin and myosin denaturation. These results suggest that heating meat at 50°C dissociates binding (‘Bond A’) between actin and myosin participating in ATPase activities, resulting in denaturation of both proteins under influence of sarcoplasmic components. Although denaturation of actin and myosin disrupted Bond A, actin was not liberated simultaneously, suggesting the presence of another bond (‘Bond B’, more heat‐stable than Bond A) between both proteins and necessity of disruption of Bond B for actin release from myofibrils.     

NAA处理对大白菜细胞壁成分和Ca~(2 )-ATPase活性的影响

ＮＡＡ处理使大白菜根对４５Ｃａ的吸收增加，提高茎叶中４５Ｃａ的积累，尤其心叶中４５Ｃａ的积累显著提高。同时，ＮＡＡ处理下根细胞壁和叶的细胞壁成分中醛酸含量和总糖含量均明显增加，其中糖和醛酸成分中的ＸＹＬ和ＧＬＣ提高５０％。ＮＡＡ处理激活大白菜根叶细胞膜的Ｃａ２＋－ＡＴＰａｓｅ的活性。     

牛肉肌纤维类型差异及成熟过程中组织蛋白酶活性研究

为考察不同部位牛肉肌纤维类型的差异、比较两种肌纤维分型方法、研究肌纤维类型对宰后成熟过程中组织蛋白酶活性的影响,选取新疆褐牛冈下肌、菱形肌、背最长肌、背阔肌、腰大肌、股二头肌、半腱肌、腓肠肌共8个部位的牛肉,分别用ATPase染色法和RT-PCR法检测肌纤维类型组成和MyHC基因相对表达量,用Image-Pro Plus6.0软件分析ATPase染色图像,计算各类型肌纤维的面积和直径,并检测各部位牛肉宰后成熟0、3、7、9、11、14 d时组织蛋白酶B、L、H活性。结果表明:新疆褐牛不同部位肉的肌纤维类型组成不同,两种肌纤维类型的分型方法在确定Ⅰ型肌纤维数量时呈极显著相关,在8个部位牛肉中,均没有发现MyHCⅡb型基因的表达,ATPase染色法确定的ⅡB型肌纤维数量百分比与RT-PCR法确定的MyHCⅡx型基因表达百分比呈显著正相关,与MyHCⅡa型基因表达百分比呈极显著负相关。两种确定肌纤维类型的方法存在一定的相关性,ATPase染色法确定的ⅡB型肌纤维可能与RT-PCR法确定的MyHCⅡx基因相对应。在宰后成熟过程中,各部位牛肉组织蛋白酶活性基本表现为先升高、后降低的趋势,不同部位的牛肉达到活性最大值的时间不同;组织蛋白酶H活性非常低,相比于组织蛋白酶B和L,其在宰后成熟中的作用可以忽略不计,组织蛋白酶L活性是B活性的2.5～4倍,在宰后成熟中起更重要的作用。Ⅰ型肌纤维数量与宰后9、11 d组织蛋白酶B和L活性呈显著甚至极显著正相关关系,在新疆褐牛各部位肉中含有的Ⅰ型肌纤维越多,组织蛋白酶活性越高,越有利于牛肉宰后成熟嫩化。     

不同基因型甘蔗组织中ATP酶活性的研究

不同基因型甘蔗叶片中的Mg~(2+)-ATP酶和Ca~(2+)-ATP酶活性与早熟高糖特性有密切的联系。原种中的春尼酶活性最高,其次是黑车里本,蔗糖分很低的野生种晋江割手密酶活性最低。五个杂交品种的这两种ATP酶活性介于春尼和晋江割手密之间;其中,早熟品种的酶活性明显较高,尤以最早熟的福引79/8最高。 在福引79/8和POJ2878幼苗的幼茎     

低温处理对豇豆幼苗生长和POD、COD、ATPase同工酶的影响

在０～１℃低温处理豇豆幼苗时幼苗生长明显受抑，检查根系和胚轴中的ＰＯＤ、ＣＯＤ、ＡＴＰａｓｅ同工酶，发现谱带减少。低温对豇豆幼苗生长的伤害与幼苗组织内三种酶同工酶的变化呈明显的相关性。上述三种酶同工酶可以作为一种生化指标用于检测植物幼苗的受寒害状况。     

敌百虫对体外培养大鼠大脑皮质神经细胞凋亡的影响

为探讨敌百虫对大鼠大脑皮质神经细胞的毒性作用及机理,本研究在建立体外培养新生24h内SD大鼠大脑皮质神经细胞模型的基础上,在细胞培养液中添加0、5、20、80mg/L敌百虫染毒,在染毒后的不同时间测定细胞凋亡率、线粒体膜电位、细胞内[Ca2＋]i、ROS含量和ATP酶的变化。结果显示：①染毒12h,细胞凋亡率明显增加;②染毒12h,各染毒组线粒体膜电位逐渐降低,其中80mg/L组与对照组存在极显著差异（P〈0.01）;③染毒0.5h,各染毒组细胞内[Ca2＋]i显著高于对照组（P〈0.01）;染毒12h,各染毒组细胞内[Ca2＋]i呈下降趋势,但仍显著或极显著高于对照组（P〈0.05或P〈0.01）;④染毒12h和24h,细胞内ROS水平显著或极显著高于对照组（P〈0.05或P〈0.01）;⑤染毒12h,细胞Na＋-K＋-ATPase和Ca2＋-Mg2＋-ATPase活性逐渐降低,20、80mg/L组与对照组有极显著差异（P〈0.01）;上述指标的变化呈显著的剂量-效应关系。结果表明,低质量浓度敌百虫暴露可致大鼠大脑皮质神经细胞凋亡率和细胞内ROS含量升高,线粒体膜电位下降,细胞内钙离子超载且ATPase活性降低,提示细胞凋亡在敌百虫所致的大脑皮质神经细胞损伤过程中发挥主导作用。     

Iron deficiency on corn root mitochondrial adenosine triphosphatase activity

Abstract

Iron deficiency significantly reduced corn root mitochondrial ATPase (adenosine triphosphatase) activity. The root mitochondrial ATPase had two pH optima. In the presence of K and Mg ions, ferrous ion stimulated the ATPase activity especially when plants were Fe‐deficient.