• 미생물학회지
• /
• 제46권4호
• /
• pp.313-318
• /
• 2010

D. radiodurans RecA 단백질은 DNA에 결합한 DNA-단백질 복합체만이 ATPase 활성을 나타내며. 보통의 낮은 염 농도조건에서는 DNA가 존재하지 않으면 RecA 단백질에 의한 ATP 가수분해는 거의 일어나지 않았으나 이러한 ATP 가수분해현상은 높은 농도의 염을 첨가하게 되면 1,000배 활성화 되었으며 1.6 M KCl이 존재할 때 ATP 혹은 dATP를 가수분해 하였다. DNA가 존재하지 않을 때 염에 의해 촉진되는 활성은 RecA 단백질 농도에 비례하였고, 더 높은 염농도에서 더 높은 ATP 가수분해 활성이 나타났다. 이러한 활성화 현상을 다양한 종류의 이온 형태에서 분석하였을 때 1.6 M Cl 음이온이 존재할 때 양이온의 형태에 따른 활성화 정도는 $K^+{\geq}Na^+$> $NH_4^+$의 경향을 보였으며, 1.6 M의 K 양이온 존재할 때 음이온의 형태에 따른 활성화는 glutamate > $Cl^-$ > acetate > $PO_4^-$의 순서로 높게 나타났다. 고농도의 염이 존재하는 조건에서 DNA 비의존성 ATPase의 활성은 비교적 넓은 범위 최적 조건인 pH7과 pH 8 사이에서 최대 활성을 보였고, 기질에 대한 친화도면에서도 외가닥 DNA 의존성 활성보다는 이중가닥 DNA 의존성 활성형태를 보였다. 고농도의 염이 첨가되고 DNA가 존재하지 않을 때 RecA 단백질에 의한 ATP 가수분해를 위한 RecA 단백질의 활성 종 형태는 최소 3개의 RecA 단백질이 결합되어 있는 과량체로 작용하는 것으로 나타났다.

• The Korean Journal of Physiology and Pharmacology
• /
• 제16권2호
• /
• pp.91-95
• /
• 2012

The role of the kidney in combating metabolic acidosis has been a subject of considerable interest for many years. The present study was aimed to determine whether there is an altered regulation of renal acid base transporters in acute and chronic acid loading. Male Sprague-Dawley rats were used. Metabolic acidosis was induced by administration of $NH_4Cl$ for 2 days (acute) and for 7days (chronic). The serum and urinary pH and bicarbonate were measured. The protein expression of renal acid base transporters [type 3 $Na^+/H^+$ exchanger (NHE3), type 1 $Na^+/{HCO_3}^-$ cotransporter (NBC1), Na-$K^+$ ATPase, $H^+$-ATPase, anion exchanger-1 (AE-1)] was measured by semiquantitative immunoblotting. Serum bicarbonate and pH were decreased in acute acid loading rats compared with controls. Accordingly, urinary pH decreased. The protein expression of NHE3, $H^+$-ATPase, AE-1 and NBC1 was not changed. In chronic acid loading rats, serum bicarbonate and pH were not changed, while urinary pH was decreased compared with controls. The protein expression of NHE3, $H^+$-ATPase was increased in the renal cortex of chronic acid loading rats. These results suggest that unaltered expression of acid transporters combined with acute acid loading may contribute to the development of acidosis. The subsequent increased expression of NHE3, $H^+$-ATPase in the kidney may play a role in promoting acid excretion in the later stage of acid loading, which counteract the development of metabolic acidosis.

• Advances in Traditional Medicine
• /
• 제5권2호
• /
• pp.137-143
• /
• 2005

Doxorubicin induces oxidative stress leading to cardiotoxicity causing electrocardiogram abnormalities and increases in biomarkers associated with toxicity. Green tea extract (GTE) is reported to possess antioxidant activity mainly via its polyphenolic constituent, catechins. This study was intended to determine the effect of various doses of GTE (25, 50 and 100 mg/kg/day p.o. for 30 days) on doxorubicin-induced electrocardiographic and biochemical changes in rat heart. The latter included lactate dehydrogenase, creatine kinase, and glutamic oxaloacetate transaminase in serum and superoxide dismutase, catalase, and reduced glutathione, as well as membrane bound enzymes like $Na^+K^+ATPase,\;Ca^{2+}ATPase,\;Mg^{2+}ATPase$ and decreased lipid peroxidation in heart tissue Results demonstrated that rats which received GTE were less susceptible to such changes indicating protection afforded by GTE.

• Nutrition Research and Practice
• /
• 제2권4호
• /
• pp.211-217
• /
• 2008

This study was purposed to investigate the effect of onion or beet on plasma and liver lipids, erythrocyte Na efflux channels and platelet aggregation in simvastatin (SIM) treated hypercholesterolemic rats. Forty Sprague Dawley rats were divided into four groups and fed 0.5% cholesterol based diets containing 2 mg/kg BW simvastatin or simvastatin with 5% onion or beet powder. Plasma total cholesterol was significantly increased in SIM group compared with the control (p<0.01), and the elevated plasma total cholesterol of SIM group was significantly decreased in SIM-onion and SIM-beet groups (p<0.05). HDL-cholesterol in SIM-beet group was significantly increased compared with other groups (p<0.05). Platelet aggregation in both the maximum and initial slope was significantly decreased in SIM group compared with SIM-onion group (p<0.05). Na-K ATPase was significantly decreased in SIM group compared with the control, SIM-onion and SIM-beet groups (p<0.05). Na passive leak was significantly increased in all groups treated with SIM compared with the control (p<0.05). The total Na efflux was decreased in SIM group and increased in SIM-onion group and the difference between these two groups was significant (p<0.05). There was no difference in intracellular Na among groups. In present study, simvastatin, a HMG CoA reductase inhibitor at dose of 2mg/kg BW/day rather increased plasma total cholesterol in rats, inferring that the action mechanism of simvastatin on cholesterol metabolism differ between rat and human. Onion and beet play favorable roles in cardiovascular system by restoring the reduced Na efflux through Na-K ATPase and Na-K cotransport in SIM treated rats.

• 대한본초학회지
• /
• 제30권5호
• /
• pp.15-21
• /
• 2015

Objectives : Methicillin-resistantStaphylococcus aureus(MRSA) is a human pathogen. New antibacterial agents are needed to treat MRSA-related infections. This study investigated the antibacterial activity of EtOH 70% extracts ofTonghyeonipal-dan(THD) which prescription is composed of oriental medicine against MRSA.Methods : The antibacterial activity of THD was evaluated against MRSA strains by using the Disc diffusion method, broth microdilution method, Checkerboard dilution test, and Time-kill test; its mechanism of action was investigated by bacteriolysis, detergent or ATPase inhibitors were used.Results : The minimum inhibitory concentration (MIC) of THD is 1,000~2,000 μg/mL against MRSA. In the checkerboard dilution test, fractional inhibitory concentration index (FICI) of THD in combination with antibiotics indicated synergy or partial synergism againstS. aureus. Furthermore, a time-kill assay showed that the growth of the tasted bacteria was considerably inhibited after 24 h of treatment with the combination of THD with selected antibiotics. For measurement of cell membrane permeability, THD 500 μg/mL along with concentration of Triton X-100 (TX) and Tris-(hydroxymethyl) aminomethane (TRIS) were used. In the other hand, N,N-dicyclohexylcarbodimide (DCCD) and Sodium azide (NaN3) were used as an inhibitor of ATPase. TX, TRIS, DCCD and NaN3 cooperation againstS. aureusshowed synergistic action.Conclusions : Accordingly, antimicrobial activity of THD was affected by cell membrane and inhibitor of ATPase were assessed. These results suggest that THD has antibacterial activity, and that THD extract offers great potential as a natural antibiotic against MRSA.

• Journal of Radiation Protection and Research
• /
• 제15권2호
• /
• pp.1-6
• /
• 1990

An attempt was made to test the possibility of a major role for the $Na^{+}-K^{+}$ adenosine triphosphatase (ATPase)system in the diuresis induced by uranyl nitrate(UN). Fisher 344 rats were intravenously injected with UN(5 mg/kg, 15 mg/kg and 30 mg/kg). Urinary excretion of $Na^{+}\;and\;K^{+}$ significantly increased in 24 h exposure on the UN and then decreased below the normal level 3 days after the treatment. $Na^{+}-K^{+}$ ATPase activity of kidney was significantly inhibited in high dosages of UN 15mg/kg and UN 30 mg/kg 3-5 days after injection. And then the recovery of the enzyme activity was observed within 5-10 days after injection, at which the regeneration of the tubular cells occurred.

• 한국임상수의학회지
• /
• 제18권3호
• /
• pp.232-236
• /
• 2001

It has been known that garlic, one of the essential ingredient in korean food, has a hypotensive effect. and it is reported that they lower the level of triglycerides, cholesterol and glucose in blood. Especially, the sulfur containing amine acid and the derivatives of the garlic has the counteracting effect to heavy metals. Nowadays, the garlic is known for its efficiency for the various kinds of cancer, neoplasms, hypertension, arteriosclerosis and apoplexy. But, it is reported that the intake of the excessive amount of garlic causes hemolytic anemia recently. The hemolytic anemia is more severe especially in HK phenotype dogs which has a Na-K-ATPase activity. Therefore, this study was performed to examine the effect on the blood of the HK phenotype Jindo dogs when administered the excessive amount of garlic. HK phenotype group showed the significant decrease on RBC, WBC, PCV, Hb, MCV, MCHC, GSH, Met-Hb but LK phenotype group didn't show the significant decrease.

• 동의생리병리학회지
• /
• 제18권1호
• /
• pp.84-92
• /
• 2004

The present study examined the effects of Taekunyukmijiwhang-tang (TV) on blood pressure and renal function in nitric oxide (NO)-dependent hypertensive rats. A phamacological inhibition of nitric oxide synthase (NOS) for 4-6 weeks produces renal vasoconstriction, renal dysfunction, and progressive severe hypertension. Treatment of rats with NG-Nitro-L-arginie methylester (L-NAME) (100 mg/L, 6 weeks), which is a nonspecific NOS inhibitor, cause a sustained increase in systolic blood pressure (SBP), along with the decrease in expression of ecNOS in the kidney and thoracic aorta. The expression of Na, K-ATPase α1 subunit in the kidney was also reduced in the L-NAME induced hypertensive rats group. The renal functional parameters including urine osmolality (Uosm), creatinine clearance (Ccr), which is an index of glomerular filtration (GFR) were decreased in rat with L-NAME induced hypertension. while solute-free water reabsoption (TcH₂O) was unchanged in all experimental group. However, the group combined treated with TV and L-NAME did not develop hypertension and expression of ecNOS in the aorta was restored. The expression of Na/sup +/, K/sup +/-ATpase α1 subunit in the kidney was markedly restored in L-NAME-induced hypertension rats by administration of TV along with the restoration of urinary volume (UV) and sodium excretion (UNaV), whlie Na/sup +/, K/sup +/-ATPase /β1 subunit was not altered. These results suggest that TV attenuates an increase in SSP in the L-NAME induced hypertension and restores partially renal function, which seems to be caused by up-regulation of expression of Na/sup +/, K/sup +/-ATPase α1 subunit in the kidney and ecNOS in thoracic aorta.

• 한국식품과학회지
• /
• 제25권2호
• /
• pp.185-190
• /
• 1993

담수산 틸라피아를 하루 $5%_{\circ}$씩 해수농도를 높여 1주일에 걸쳐 $32%_{\circ}$ 해수에 순화시켜, 이때를 기준(0주)으로하여 1주일 간격으로 염세포의 발달, 근육의 물성 및 미량원소의 변화와 더불어 근원심유의 ATPase 활성 및 열안정성에 대한 변화를 알아보았다. 아가미의 염세포는 해수순화와 더불어 점진적으로 갯수가 늘어나고 크기가 커져 순화 3주째에 발달이 완료되었다. 근육의 절단 및 압착강도도 해수순화에 따라 현저히 증가하여 근육의 물성변화를 보였으며, 일부 미량원소 (Mg, Na, K)도 뚜렷한 측적을 나타내었다. 근원섬유 ATPase 활성은 해수순화와 더불어 담수산의 것에 비해 유의차를 보이며 증가하였다. 근육중의 미량원소의 증가와도 관련이 있을 것으로 보이는 근원섬유 ATPase 활성증가는 결국 근육중의 ATP 분해를 촉진하여 근수축을 신속히 유도, 근육의 탄력을 증대시킴으로써 식감이 개선되는 것으로 추측되었다. 한편, 근원섬유의 열안정성은 해수순화에 의해 현저히 저하되었다.

• Journal of Animal Science and Technology
• /
• 제61권2호
• /
• pp.87-97
• /
• 2019

Phytate induced excessive mineral excretion through poultry litter leads to poor performance and environmental pollution. Exogenous microbial phytase supplementation to poultry diets reduce the environmental excretion of nutrient and improve bird's performance. However, excessive dietary sodium (Na) level may hinder the phytase-mediated phytate hydrolysis and negate the beneficial effects of phytase. Therefore, this experiment was conducted to investigate the effects of different concentration dietary Na on phytase activity and subsequent impact on broiler performance, bone mineralisation and nutrient utilisation. In this study, six experimental diets, consisting of three different levels of Na (1.5, 2.5, or 3.5 g/kg) and two levels of microbial phytase (0 or 500 U/kg) were formulated by using $3{\times}2$ factorial design. The six experimental diets were offered to 360 day-old Ross 306 male chicks for 35 days, where, each experimental diet consisted of 6 replicates groups with 10 birds. Along with growth performance, nutrient utilization, intestinal enzyme activity, dry matter (DM) content of litter and mineral status in bone were analysed. Dietary Na and phytase had no effect on bode weight gain and feed intake. Birds on the low Na diet showed higher (p < 0.05) feed conversion ratio (FCR) than the mid-Na diets. High dietary Na adversely affected (p < 0.001) excreta DM content. Phytase supplementation to the high-Na diet increased (p < 0.01) the litter ammonia content. High dietary Na with phytase supplementation improved ($Na{\times}phytase$, p < 0.05) the AME value and ileal digestibility of Ca and Mg. The total tract retention of Ca, P, and Mg was reduced with high Na diet, which was counteracted by phytase supplementation ($Na{\times}phytase$, p < 0.001). The diets containing mid-level of Na improved (p < 0.001) the function of Na-K-ATPase and Mg-ATPase in the jejunum. The overall results indicate that high dietary Na did not affect phytase activity but influenced the nutrient utilization of birds, which was not reflected in bird overall performance.