糖芥总甙对大鼠心肌和大脑Na~ ,K~ -ATP酶活力的影响

用测定无机磷含量法研究了糖芥总甙对ｗｉｓｔａｒ大鼠心肌和大脑Ｎａ＋,Ｋ＋－ＡＴＰ酶活力的影响。实验结果表明,糖芥总甙能明显抑制大鼠心肌大脑Ｎａ＋,Ｋ＋－ＡＴＰ酶活力,且呈量效关系。实验证实糖芥总甙的强心机制与西地兰类强心甙相同     

中华补血草不同器官Na^＋,K^＋含量的比较研究

本文研究表明:中华补血草不同器官以及同一器官不同部位Na~+、K~+离子的含量具有明显差异。中华补血草根Na~+、K~+含量高于地上部分,肉质根具有贮盐作用,幼龄叶的Na~+的含量低于中龄叶和老龄叶,而K~+的含量则相反。在根——茎部位中皮层部分的Na~+、K~+含量高于中柱部分。本文认为中华补血草不同器官的抗盐性是不同的。     

盐碱胁迫对燕麦水势、干物质积累率以及K+、Na+选择性吸收的影响

研究了自然盐碱胁迫对燕麦植株水势、干物质积累率以及对K 、Na 选择性吸收的影响,结果表明,随着土壤盐浓度的升高燕麦叶片和根系的水势较对照均有所降低,其中裸燕麦较皮燕麦水势下降幅度大。干物质积累率的变化规律表现为:在盐碱胁迫下燕麦各生育时期的干物质积累率随着盐碱浓度的增大而增大,各盐碱处理的干物质积累率大于对照(个别处理除外)。随着盐碱浓度的升高植株对Na 的吸收增加,K 的吸收受抑制,从而使Na /K 和S Na K 值升高,在同一处理内叶片的Na /K 最高,穗中Na /K 最低。图1,表4,参14。     

心肌Na+-Ca2+ 交换和缺氧-复氧

心肌细胞Na^ -Ca^2 交换在缺氧．复氧条件下通过Na^ -H^ 交换、持续性钠电流等途径使胞内Na^ 升高，进而在去极的静息膜电位、氧自由基共同作用下促进反向的Na^ -Ca^2 交换，导致胞内Ca^2 超栽。Ca^2 超栽引起心肌再灌注损伤、心律失常的发生和细胞高度挛缩甚至死亡。深入研究和探讨缺氧．复氧时Na^ -Ca^2 交换导致心肌损伤的机理，对于研发临床用于心肌保护的药物有重大意义和广阔前景。     

盐胁迫对大麦根和叶生长及其Na~+、Cl~-和K~+含量的影响

低浓度NaCl使大麦叶片生长受到抑制,但对根的生长却有一定促进作用。根中Na~+含量随NaCl浓度增加而急剧增加,叶片则缓慢增加,而叶片中Cl~-含量却始终远高于根中,而且增加量也大于根。与Na~+、Cl~-含量相反,根和叶中K~+含量则均随NaCl浓度增加而下降,根中Na~+和Cl~-含量开始随胁迫时间的延长很快增加,但第3天后下降,叶中Na~+含量始终缓慢增加,而叶中Cl~-含量随胁迫时间的延长而急剧增加。根和叶中K~+含量均随胁迫时间延长而下降。     

The ATP synthase (F0−F1) complex in oxidative phosphorylation

The transmembrane electrochemical proton gradient generated by the redox systems of the respiratory chain in mitochondria and aerobic bacteria is utilized by proton translocating ATP synthases to catalyze the synthesis of ATP from ADP and P_i. The bacterial and mitochondrial H⁺-ATP synthases both consist of a membranous sector, F₀, which forms a H⁺-channel, and an extramembranous sector, F₁, which is responsible for catalysis. When detached from the membrane, the purified F₁ sector functions mainly as an ATPase. In chloroplasts, the synthesis of ATP is also driven by a proton motive force, and the enzyme complex responsible for this synthesis is similar to the mitochondrial and bacterial ATP synthases. The synthesis of ATP by H⁺-ATP synthases proceeds without the formation of a phosphorylated enzyme intermediate, and involves co-operative interactions between the catalytic subunits.     

一次急性运动对血液抗氧化能力和Na+-K+-ATPase的活性的影响

20只小鼠随机分成对照组和运动组。运动组小鼠进行45min游泳后即刻与安静对照组同时从眼眶取血样，测试血清内抗氧化物质超氧化物歧化酶(SOD)和脂质过氧化反应的代谢产物丙二醛(MDA)，同时测试了反映红细胞膜结构完整性的Na^ -K^ -ATPase的活性和反映体内代谢状况的血乳酸。结果显示：一次急性运动后SOD活性有上升趋势，MDA和血乳酸浓度水平明显升高，Na^ -K^ -ATPase的活性变化不大。本研究旨在通过探讨短时问、低强度运动对机体上述指标的影响，为中低强度的健身锻炼提供理论依据。     

H+-ATPase in the plasma membrane of Arabidopsis pollen cells is involved in extracellular calmodulin-promoted pollen germination

-activated Ca2+ channel in the PM of A.thaliana pollen cells.     

Phospholipid composition of cardiac (Na++K+)-ATPases from various species

Summary There is a difference in phospholipid composition of cardiac (Na⁺+K⁺)-ATPase preparations between species which are sensitive to ouabain and those which are not. Sphingomyelin is higher and phosphatidylcholine is lower in the enzymes from sensitive species than in those from insensitive ones. Lysophosphatidylcholine is detectable only in the latter preparations.