• Environmental Analysis Health and Toxicology
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• v.19 no.3
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• pp.279-286
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• 2004

Although numerous studies have shown that cadmium disturbs the normal biological processes in central nervous system, the mechanism of toxicity is not well understood. The present study has investigated the effect of cadmium on oxidative stress, Na$^{+}$K$^{+}$ ATPase activity and the aggregation of amyloid beta peptide ($\beta$-amyloid) in neuronal cell line, HT22 cell. LC$_{5}$ and LC$_{50}$ of cadmium for HT22 cell resulted from MTT assay was 4.1 uM and 9.5 uM, respectively. Cadmium (2 to 8 uM) dose-dependently increased the lipid peroxidation and decreased the content of glutathione. Cadmium 4 uM showed a significant decrease in Na$^{+}$/K $^{+}$ ATPase activity as compared with control group. The aggregation of $\beta$-amyloid was accelerated in a dose-dependent manner by the treatment with 2 to 8 uM cadmium. These results suggest that the neurotoxicity of cadmium can be mediated by the increase in oxidative stress and decrease in Na$^{+}$/K$^{+}$ ATPase activity.se activity.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.300-300
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• 1994

$Na^{+}$,$K^{+}$-ATPase activity, $Na^{+}$-dependent phosphorylalion, and [$^3$〕ouabain binding in sarcolemma prepared from 4 week old spontaneously hypertensive rat(SHR) ventricles were compared to the same parameters in sarcolemma from age matched normotensive Wistar-Kyoto(WKY) rat ventricles to examine whether the reduced myocardial $Na^{+}$-pump activity in SHR is an inherited enzymatic defect or a second phenomenon due to sustained hypertension. The total body weights, ventricular weights, and blood pressures were the same for SHR and WKY. No significant differences in sarcolemmal protein content and protein recovery were noted between the two pups. Sarcolemma isolated from SHR ventricles showed sigificantly less $Na^{+}$,$K^{+}$-ATPase activity and number of phosphorylation sites when compared to snrcolemma 1mm the WKY ventricles. Equilibrium binding of [$^3H$〕ouabain and the turnovcr number of myocardial $Na^{+}$,$K^{+}$-ATPast however, wee the same for both groups. These results. indicate that the low affinity(${\alpha}$, or ${\alpha}_1$) isoform for ouabain is reduced in SHR compared to WKY but that the high affinity(${\alpha}$+, or ${\alpha}_2$) isoform is the same in ventricles of SHR and WKY. The reduced amount of at isoform of the $Na^{+}$,$K^{+}$-ATPasc in prehypertensive SHR ventricles may play some pole in the development of hypertension.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.734-738
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• 1996

The development of the alpha2 isoform of (Na,K)ATPase which is high affinity ouabain receptors was studied in the differentiating nonfusing muscle cell line BC3H-1. T he differentiation process of BC3H-1 cell line was confirmed by 2-dexy-D-[$^3$H] glucose uptake experiment and the quantity of the expression of ${\alpha}_2$ isoform was measured using a whole cell [$^3$H] ouabain-binding assay. Undifferentiated growing BC3H-1 cells, myoblasts, exhibited low levels of insulin-stimulated glucose uptake and [$^3$H] ouabain-binding sites. In contrast, differentiated BC3H-1 cells, myocytes, had a 5.6-fold increase in insulin-stimulated glucose uptake and 5-fold increase in [$^3$H] ouabain-binding sites. Scatchard analysis showed that myocytes developed more [$^3$H] ouabain-binding sites than myoblasts vath a dissociation constant (kd) of 6${\times}10^{-8}$M and capacity of 6.l${\times}10^{-5}$ sites/cell. Therefore. it seems that myoblasts express low levels of ${\alpha}_2$ subunit and probably the majority of ${\alpha}_1$ subunit, whereas myocytes express high levels of ${\alpha}_2$ isoform. The results indicate that the expression of ${\alpha}_2$ isoform is developmentally regulated during differentiation and that BC3H-1 culture system provides an excellent model for the study of differentiation and mechanism of (Na,K)ATPase action in muscle which requires electrical excitability.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.1-8
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• 1991

In attempts to evaluate carcinogenic chemical effect on $Na^+,K^+$-ATPase activity in the rat submandibular gland tumor induced by DMBA, pellet from DMBA powder was inserted into the right submandibular gland. Both right and left submandibular gland were excised and weighed following the period of experiment. Excised glands were observed microscopically and estimated biochemically. The results were obtained as follows. 1. Swelling and nodular mass in the right submandibular gland region ould be found at 11th week post-implantation with DMBA. 2. The weight and size of the right submandibular gland was markedly increased following the period of the experiment. 3. Epithelial dysplasia and invasive epidermoid carcinoma could be observed at 7th and 11th week after implantation of DMBA, respectively. 4. The rate of tumor induction in the right submandibular gland was about 76% at 17th week following implantation of DMBA. 5. DMBA caused markedly depressed $Na^+,K^+$-ATPase activity as well as the activity ratio in the rgiht submandibular gland following the period of experiment.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.220-228
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• 1997

Background The stenosis of the coronary artery may decrease myocardial oxygen supply and occur myocardial ischemia or infarction. Soojeomsan, one of analgesics is generally regarded to have the effect of vitalizing blood, expelling blood stasis and alleviation cardiac pain. Methods The purpose of this experimental study is to find the influence of Soojeomsan on cardiac enzyme (CPK, Na-K ATPase) of ischemic and reperfused rat hearts which are isolated under the Langendorff apparatus. Ischemia was induced In isolated hearts of Sprague-Dawley rats by ceasing the perfusion for 20 minutes. The experiments were divided into a normal saline orally administered group(control group), a Soojeomsan orally 20ml administered group(sample A) and a Soojeomsan orally 30ml administered group(sample B). The CPK (creatinine phosphokinase) and Na-K ATPase activity of this three group were measured and compared in order to assess the influence of Soojeomsan on protection of isolated rat hearts from ischemia. Results 1. CPK was significantly reduced in Sample A group and Sample B group in comparison with control group in reperfusion(P<0.01), and there were no significant difference between Sample A and B. 2. Na-K ATPase activity was significantly increased in Sample A group and Sample B group in comparison with control group in ischemia(P<0.001), and the activity was significantly higher in Sample B then in Sample A.(P<0.01) 3. There were no significant difference in Na-K ATPase activity of the three groups after reperfusion. Conclusion Soojeomsan has effects to decrease CPK activity and activate Na pump. This result in protection of the myocardium of isolated rat hearts from ischemia.

• The Korean Journal of Physiology
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• v.8 no.1
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• pp.55-65
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• 1974

The effect of ginseng on the ATPase activity of rabbit ref cell membrane has been investigated. The experiments were also designed to determine whether the components of ginseng could be attributed to the effect on ATPase activity which dependent upon sodium plus potassium and is sensitive to ouabain. The following results were observed. 1. The activity of the $Na^{+}-K^{+}-ATPase$ from red cell membrane is stimulated by ginseng, and the concentration of ginseng for half-maximal activity is about 15 mg%. The pH optimum for the ginseng sensitive component is 7.6. 2. The portion of the enzyme activity stimulated by ginseng is completely abolished by ouabain. 3. The activating effect of ginseng on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but activity ratio is decreased. 4. The activating effect of ginseng on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but the activity ratio is decreased. 5. The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts and the rate of activity by ginseng is constant. 6. The action of ginseng on the ATPase activity was not related to the sulfhydryl group of cysteine, the amino group of lysine, the imidazole group of histidine, the quanidinium group of arginine, the carboxyl group of aspartic acid, or the hydroxyl group of threonine. 7. The activating effect of ginseng on the ATPase activity may be not due to a saponin which is contained in ginseng.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.202-208
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• 1997

In order to investigate the mechanisms of epithelial ion transports, microsomes of soybean roots were prepared and the activity of microsomal ATPases was measured by an enzyme-coupled assay. The effects of various ions were evaluated on the total activity of microsomal ATPases and the average activity was 190 nmol/min/mg protein in the control solution containing $10\;mM\;Na^+\;and\;120\;mM\;K^+$. The activities were increased to 150% and decreased to 63% of the control activity in the solution containing $130\;mM\;K^+$ without $Na^+$ and in the solution containing $130\;mM{\;}Na^+$ without $K^+$, respectively. In general, the activity of microsomal ATPase was increased by$K^+$ in a concentration-dependent manner The activity was also increased at lower pH and relatively higher activities were observed in the pH range of $6{\sim}7$. However, the activity was decreased at weak alkaline $pH\;and{\sim}80%$ of the activity was inhibited at pH 9. Since intracellular $Ca^{2+}$ has been known to control the activity of various enzymes, we have investigated the effects of intra-and extrarnicrosomal $Ca^{2+}$ on the activity of microsomal ATPases. The maximal activity was obtained at the extrarnicrosomal $Ca^{2+}$ concentrations below 1 nM. The activity was gradually decreased by increasing $‘Ca^{2+}’$ concentration and 50% inhibition was observed at ${\sim}500{\;}{\mu}M{\;}Ca^{2+}$. The increase in luminal $Ca^{2+}$ concentration also inhibited the activity of microsomal ATPase. When the influx of external $Ca^{2+}$ was induced by $Ca^{2+}$ ionophore A23187 treatment, the activity was decreased by 30%; however, it was recovered by EGTA-induced chelation of $Ca^{2+}$. These results suggest that the presence of $Ca^{2+}$ regulation sites on both cytoplasmi and luminal sides of microsomal ATPases.

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.203-213
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• 1985

This study was carried out to investigate whether the K-pNPPase activity in renal cortical slices can be used as an index for measuring the activity of $Na^+-K^+$ exchange pump. The K-pNPPase activity, Ouabain-sensitive oxygen consumption add intracellular electrolytes content in slices, and Na-K-ATPase activity in microsome were measured and the effects of ouabain and vanadate on these were observed. The results are as follows : 1) p-NPPase activity in slices increased linearly with incubation time during 60 minutes, and $K^+$-dependent, ouabain-sensitive fraction was about 55% of total p-NPPase activity. This value was almost the same through out the incubation time. 2) The concentrations of ouabain and vanadate for 50f inhibition of K-pNPPase activity were$7.0{\times}10^{-6}M$ and $1.3{\times}10^{-5}M$, respectively. 3) The ouabain-sensitive oxygen consumption in slices was reduced to 50% of control value by $6.3{\times}10^{-6}M$ ouabain or $2.5{\times}10^{-5}M$ vanadate. These concentrations were similar to those for 50% inhibition of K-pNPPase activity. 4) The trends of intracellular electrolytes change by ouabain and vanadate were similar to those of the change in K-pNPPase activity. 5) The Na-K-ATPase activity in microsome prepared from renal cortex was completely inhibited by $10^{-3}M$ ouabain or $10^{-3}M$ vanadate and the concentration for 50% inhibition was $1.2{\times}10^{-6}M$ in ouabain and $1.6{\times}10^{-6}M$ in vanadate, which were much lower than those for K-pNPPase activity or ouabain-sensitive oxygen consumption in slices. These results indicate that K-pNPPase activity measured in renal cortical slices is a better index for evaluating $Na^+-K^+$ exchange pump activity than Na-K-ATPase activity measured in microsome.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.8-16
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• 1996

Effects of water extract of aloe vera on lead-induced neurotoxicity were investigated in sciatic nerve isolated from rat. The mechanism on toxicity reduction by measuring activities of axonal enzymes, metabolism of myo-inositol in nerve, lead concentration in several organs and so on were further examimed. In the lead-treated rats, the transport rate of axonal enzyme, such as acetyl cholinesterase and choline acetyltransferase, was reduced by from 50% to 30% respectively. Reduction in myo-inositol concentration and $Na^+/K^+$ ATPase activity were also observed in sciatic nerve from lead-treated rat. However, the aloe extract administration significantly eliminated the impairment and maintained myo-inositol concentration to about 85% of normal level. Also aloe extract promoted the excretion rate of lead which is accumulated in blood, sciatic nerve and kidney. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of aloe extract and the mechanism might be partly increase in kidney excretion rate of lead and parity normalization of $Na^+/K^+$ ATPase activity which is critical factor in order to keep nerve maintaining normal myo-inositol level.

• Journal of Nutrition and Health
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• v.19 no.3
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• pp.135-145
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• 1986

식이 $\omega$3 지방산이 신장의 지질구성 및 기능에 미치는 영향을 조사하기 위해 젖뗀 55-60 g의 흰쥐에게 고등어유, 들깨유, 콩기름을식이의 10% (W/W)포함하는 먹이를 조제하여 24일간 섭취시켰다. 고등어유군의 신장 인지질 지방산에 C20~C22 $\omega$ 3 지방산의 함량이 월등히 많은 반면 들깨유군은 콩기름군에 비해 약간 높을 뿐이어서 C18 : 3 ($\omega$3) 지방산으로 단기간에 쉽게 전환되지 않음을 보였다. C18 : 2($\omega$6) 지방산은 고등어군만 낮았고 C20 : 4($\omega$6)는 들깨유군에서는 낮았지만 고등어유군은 콩기름군과 같은 수준이었다. 또한 고등어유군에서 C18 : 1($\omega$9)을 포함한 단일 불포화 지방산이 높고 포화지방산 함량이 낮은 것도 특징이었다 . 인지질 종류별 분석결과에서 고등어유군이 sphingomyelin 이 높고 phosphatidylethanol-amine이 낮았다. 반면 신장 Cholest대기 함량은 고등어유군이 높았으며, 이러한 지질구성 변화는 신장 Na-K-ATPase 활성감소시킨 것이다.