• Journal of Microbiology and Biotechnology
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• 제10권4호
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• pp.441-448
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• 2000

The production and cation flux-mediated activation of the P-type ATPase in Helicobacter pylori was investigated. Using the polymerase chain reaction (PCR), the proton pump genotype of H. pylori was found to be positive for both F-type and P-type ATPases. Yet, their production in terms of enzyme specific activity varied substantially depending on H. pylori strains, ranging over 3-fold. Its main constituent appeared to be the P-type ATPase pool, in contrast to other common bacterial compositions. Interestingly, the F-type ATPase was observed only when intact H. pyloricells were exposed to pH 4.5 or above (37$^{\circ}C$ for 1 h). In contrast, significant amounts of the P-type ATPase still remained after 1 h of cell treatment even at pH below 4.5. By enriching the acidic medium with RPMI(pH 3.0), the P-type ATPase was stabilized, accompained by inactivation of the F-type ATPase. Using H. pylori membrane vesicles, it was found that ammionia-mediated cation flux increased the rate of ATP hydrolysis by the P-type ATPase. Accordingly, these data strongly suggest that the P-type ATPase is involved or functions as an effective regulator for the cation flux across the H. pylori membrane, thereby reducing the risk of excess proton influx.

• Environmental Analysis Health and Toxicology
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• 제9권1_2호
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• pp.1-8
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• 1994

Nerve conduction impairment in lead neuropathy has been empirically linked to altered nerve myo-inositol metabolism. In most cases of neuropathy, abnormal myo-inositol metabolism is associated with abnormal $Na^+/K^+$ATPase provides a potential mechanism to relate defects of the myo-inositol metabolism in the peripheral nerve treated with lead. Therefore, the effect of lead on the rat sciatic nerve $Na^+/K^+$ATPase and other ATPase of sciatic nerve was studied. ATPase activity was measured enzymatically in sciatic nerve homogenates from 2-wk lead treated neuropathy rats and age-mached controls administered myo-inositol. $Na^+/K^+$ATPase components were assessed by ouabain inhibition or the omission of sodium and potassium ions. Lead reduced 50% reduction in the $Na^+/K^+$ATPase activity in homogenates of sciatic nerve. The 50% reduction in the $Na^+/K^+$ ATPase activity was selectively prevented by myo-inositol treatment. This study suggests that the toxic mechanism of the lead on peripheral nerve may be through reduction in $Na^+/K^+$ATPase activity which has been linked to axonal transport slowing in the rat model of lead neuropathy, via direct changes by the perturbation of the intracelluar sodium or potasium level.

• The Korean Journal of Physiology
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• 제8권1호
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• pp.67-76
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• 1974

The effect of saponin on the sodium plus potassium activated ATPase activity was studied in the rabbit red cell ghosts and the experiments were also designed to determine the mechanism of action of saponin on the APTase activity. The following results were observed. 1. The ATPase activity of rabbit red cell ghosts is inhibited by low concentration of saponin but increased by high concentration. The activating effect of saponin on the $Na^{+}-K^{+}-ATPase$ activity is inhibited by ouabain but the stimulation of the $Mg^{++}-ATPase$ by high concentration of saponin is not inhibited by ouabain. 2. The activity ratio of $Na^{+}-K^{+}-ATPase$ by high concentration of saponin is decreased by raising the potassium concentration, and is increased by raising the sodium concentration. 3. The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts. The activity ratio of the enzyme by saponin is decreased by raising the calcium concertration 4. The action on the ATPase activity was not related to the amino group of lysine, the hydroxyl group of threonine, the imidazole group of histidine, or the carboxyl group of aspartic acid. 5. The action of saponin on the ATPase activity is due to sulfhydryl group of the enzyme of $Na^{+}-K^{+}-ATPase$.

• The Korean Journal of Physiology
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• 제12권1_2호
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• pp.15-23
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• 1978

The action of ascorbic acid on the sodium Plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action if ascorbic acid on the ATPase activity The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by ascorbic acid and the concentration of ascorbic acid for maximal activity is about 8 mM. 2. The activating effect of ascorbic acid on the ATPase activaty, with a given concentration of sodium in the medium, is increased by raisins the potassium concentration but activity ratio is decreased. 3. The activating effect of ascorbic acid on the ATPase activity, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 4. The action of ascorbic acid on the ATPase activity is stimulated by calcium ions and activity ratio is increased by raising the calcium concentration. 5. The activating effect of ascorbic acid on the ATPase activity was not related to the sulfhydryl group of cysteine or the hydroxyl group of threonine. 6. The activating effect of ascorbic acid on the ATPase activity is due to amino group and carboxyl group of the enzyme of NaK ATPase.

• The Korean Journal of Physiology
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• 제12권1_2호
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• pp.25-34
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• 1978

The action of theobromine on the sodium plus potassium activated ATPase activity In the rabbit red cell membrane has teen investigated and the experiments were also designed to determine the mechanism of action of theobromine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red fell membrane is stimulated by theobromine, and the concentration of theobromine for maximal activity is about 3mM. 2. The activating effect of theobromine on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 3. The activating effect of theobromine on the ATPase, with a given concentration of sodium in the medium. is increased by the raising the potassium concentration but activity ratio is decreased. 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by larger amounts. The activity of the enzyme by theobromine is increased by small amounts of calcium but decreased by larger amounts. 5. The activating effect of theobromine on the ATPase was not related to the hydroxyl group of threonine and imidazole group of histicline. 6. The activating effect of theobromine on the ATPase is due to sulfhydryl group, amino group and carboxyl group of the enzyme of NaK ATPase.

• 대한약리학회지
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• 제2권2호
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• pp.35-42
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• 1966

The author investigated the effect of $Mg^#$, $Ca^#$, $Na^+$, $K^+$ and creatine phosphate on the ATPase activity of microsomal fraction isolated from rabbit uterus and obtained the following results : 1) The uterine microsomal fraction contained the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. The ATPase activity increased with protein content in the fraction. 2) The maximum ATPase activity was obtained at $Na^+$ and $K^+$ concentraction of 100 mM respectively. 3) In the absence of $Mg^#$, the ATPase was not activated by $Na^+$ and $K^+$, but inhibited. 4) Car stimulated the $Na^+-$ and $K^+-$ activated ATPase in the presence of $Mg^#$. However, in the absence of $Mg^#$, the ATPase was not activated by $Ca^#$. 5) The $K^+-$ activated ATPase activity was greater than the $Na^+-activated$ ATPase under all conditions. 6) The $Na^+-$ and $K^+$ activated ATPase activity was increased by addition of creatine phosphokinase and creatine phosphate to the reaction mixture.

• KSBB Journal
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• 제11권5호
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• pp.518-523
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• 1996

효소 purine nucleoside phosphoryrase(NP)하 고 xanthine oxidase(XOD) 두 효소를 하나로 고정화시켜 산소 전극으로부터 ATPase 활성 계측용 바 이오 센서를 개발했다. 개발된 ATPase센서를 이용 해서 Thunnus albacares(Yeliowfin tuna), Tetra~ t turus audax(Striped marlin), Prognichthys agoo (Japanese flyingfish) 그리고 Cyprinus carpio ( ( Carp) 등의 각 4종의 어근육 단백질중의 $K^+-, Ca^{2}+- 그리고 Mg^{2+}-$ATPase 활성을 측정하였고, 시료 1 개를 측정는데 3분의 시간을 필요로 하였다. $K^+-, Ca^{2}+-$ATPase 활성의 경우 본 연구에셔 개발한 센 셔를 이용한 측정 결과와 종래(비색측정)법으로 측 정한 결과와의 사이에서 좋은 상관치를 얻었다.

• The Korean Journal of Physiology
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• 제11권1호
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• pp.11-20
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• 1977

The action of pilocarpine on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of pilocarpine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by pilocarpine, and the concentration of pilocarpine for maximal activity is about 3 mM. The pH optimum for the pilocarpine sensitive component is 8.0. 2. The activating effect of pilocarpine on the ATPase, with a given concentration of sodium .in the medium, is increased by raising the potassium concentration but activity ratio is decreased 3. The activating effect of pilocarpine on the ATPase, with a given concentration of Potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by 'larger amounts. The activity ratio of the enzyme by pilocarpine is decreased by small amounts .of calcium but decreased by larger amounts. 5. The activating effect of pilocarpine on the ATPase was not related to the sulfhydryl group of cysteine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The activating effect of pilocarpine on the ATPase is due to amino group and carboxyl group of the enzyme of NaK ATPase

• 약학회지
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• 제22권3호
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• pp.120-127
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• 1978

We have studied the effect of ouabain, tool ginseng saponin, panax saponin C (protopanaxatriol derivative) and ginsenoside $Rb_{1}$ (protopanaxadiol derivative) on $Na^+,K^+$-ATPase and $Mg^{++}$-ATPase activities were determined by the method of Robinson and ATPase activities were determined by the method of King. The $Na^+,K^+$-ATPase activities were inhibitied by 90.1% and 51.1% respectively at the concentration of $10^{-3}M$ and $10^{-4}M$ ouabain. The results are consistent with those of Robinson. The $Na^+,K^+$-ATPase activities were increased by 14.3% and 10.0% respectively at the concentration of $10^{-4}$g/ml and $10^{-5}$g/ml total ginseng saponin. Panax saponin C obtained by the method of Han and ginsenoside $Rb_{1}$ obtained by the method of Shibata were used. The $Na^+,K^+$-ATPase activities were increased in the presence of panax saponin C and the increased activity with panax saponin C was greater than that with total ginseng saponin. On the other hand ginsenoside $Rb_{1}$ showed an inhibitory effect on $Na^+,K^+$-ATPase. Total ginseng saponin, panax saponin C and ginsenoside $Rb_{1}$ had no effect on $Mg^{++}$-ATPase. Therefore, it may be concluded that total ginseng saponin has dual effects on microsomal $Na^+,K^+$-ATPase, that is, panax saponin C exhibits stimulatory action, whereas ginsenoside $Rb_{1}$ shows inhibitory action.

• The Korean Journal of Physiology
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• 제17권2호
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• pp.161-168
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• 1983

Studies on the effects of vanadate for Na-K-ATPase activity were carried out with rabbit renal cortex. 1) Na-K-ATPase activity was inhibited with the concentrations of vanadate in incubation medium. The vanadate concentration at which activity was inhibited by 50%$(ID_{50})$ was $10^{-6}M$ and Hill coefficient was 1.00. 2) The fractional inhibition by constant concentration of vanadate decreased with increasing enzyme concentration. 3) Increasing $K^+$ and $Na^+$ concentrations in incubation medium diminished the ability to inhibit Na-K-ATPase by vanadate whereas increasing $K^+$ and $Mg^{2+}$ concentrations potentiated the inhibition of Na-K-ATPase by vanadate. 4) Vanadate didn't inhibit Na-K-ATPase at pH 6.6. Increasing pH potentiated the inhibition of Na-K-ATPase activity. 5) Vanadate inhibited Na-K-ATPase activity reversibly in all range of concentrations in dilution experiment. These results show that vanadate inhibits Na-K-ATPase activity with interacting at $KE_2$ state reversibly.