• The Korean Journal of Pharmacology
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• v.18 no.2
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• pp.69-77
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• 1982

$Na^+,\;K^+-ATPase$ is a component of plasma membrane in almost all animal cell, and maintains ionic distribution and membrane potential of normal cell. In the mechanism of adrenergic transmission, it is relatively well known that drug-receptor combination leads to stimulate adenylate cyclase and so on. In the cholinergic transmisison, the mechanism is not well known but is simply interpreted as the change of membrane permeability results from acetylcholine receptor interaction. To study the relationship between cholinergic transmission and membrane $Na^+,\;K^+-ATPase$, the effect of carbachol on $Na^+,\;K^+-ATPase$ activity in rabbit erythrocyte membrane is studied. The results are summarized as follows. 1) Total ATPase, $Mg^{+2}-ATPase$ and $Na^+,\;K^+-ATPase$ of rabbit erythrocyte membrane show maximum activities at 1mM of tris-ATP. 2) Total ATPase activity tends to increase when treated with carbachol $(10-^{-9}M-10^{-3}M)$. 3) The $Mg^{+2}-ATPase$ activity also tends to increase when treated with carbachol $(10-^{-9}M-10^{-3}M)$. 4) The $Na^+,\;K^+-ATPase$ activity is inhibited when treated with carbachol $(10-^{-9}M-10^{-7}M)$. It is suggested that the inhibition of $Na^+,\;K^+-ATPase$ by cholinergic drugs may be considered as one part of mechanism of cholinergic transmission.

• Journal of Nutrition and Health
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• v.11 no.3
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• pp.37-42
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• 1978

Actomyosin and myofibril were extracted from Korean native Goat muscle with the Weber-Edsall solution. ATPase activities and physiochemical properties were measured. The results obtained were as follows; 1) Mg-activitied ATPase activity of actomyosin and myofibrill from Korean native Goat muscle exhibited a common biphasic response, a typical ATPase pattern, that is high at a low ionic strength and low at a high ionic strength. Actomyosin showed high activity than myofibrill. 2) Mg-activited ATPase activity of actomyosin from muscle increased extraction time 24 hours. 3) EDTA-enhanced ATPase activity of actomyosin was greater than myofibrill and low at the low ionic strength, high at the high ionic strength. The difference of the activity were shown great broad pattern at the after 0.3M KCI concentration. 4) Effect of EGTA on-ATPase activity of myofibrill and actomyosin from muscle was measured, the Mg-ATPase activity was markedly depressed. 5) Solubility of actomyosin from muscle began to solubilize at KCI concentration of 0.28M and solubilized completely at the KCI concentration of 0.3M.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.647-653
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• 1997

To establish the index of aging stage for cold storage beef tenderloin, shear force value(SFV), Mg-ATPase activity, myofibrillar fragmentation index(MFI), myofibrillar fragmentation ratio(MFR) and appearance of 30KD(30KD) were measured as the parameters for the indices of aging stage. Aging index of air-packed beef tenderloin stored for 14 days at 3$^{\circ}C$ were useful in the order of SFV(r=-0.893)>MFR (r=0.863) >30KD(r=0.853)>MFI(r=0.814)>Mg-ATPase activity(г=0.804). Vacuum-packed beef tenderloin stored for 28 days at 3$^{\circ}C$ were useful in the order of MFR(r=0.880)>30KD(r=0.836). In case of the correlation between aging indices of air-packed beef tenderloin, MFR had relation with SFV, Mg-ATPase activity, MFI and 30KD. In case of the correlation between aging indices of vacuum-packed beef ten- derloin, MFR had relations with 30KD.

• The Korean Journal of Zoology
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• v.15 no.4
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• pp.163-182
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• 1972

The effects of caffeine on the ATPase activity and Ca uptake of the fragmented sarcoplasmic reticulum isolated from rabbit skeletal muscle were studied. The ATPase activity of the heavy fraction (2,000-8,000xG) was stimulated by caffeine while that of other lighter fractions was not. It is suggested that the enhancement of the ATPase by the caffeine treatment. The Ca uptake of the heavy and middle (10,000-20,000xG) fractions was inhibited by caffeine when measured at the medium Ca concentration higher than 200 nmoles/mg protein, while only that of the heavy fraction was inhibited when measured at the Ca concentration below 200 nmoles/mg protein. Experiments with dicumarol suggested that caffeine inhibits the Ca uptake of the mitochondria as well as that of the sarcoplasmic reticulum and that the inhibition of the Ca uptake by caffeine in the low Ca concentration in the heavy fraction is due to the inhibition of the mitochondrial Ca uptake by caffeine. It appeared highly probable that the potentiation of muscle contraction caused by caffeine is solely due to the inhibition of the Ca uptake by and to the release of the accumulated Ca from the sarcoplasmic reticulum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.348-352
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• 1992

Investigation on the characteristics of actomyosin was prepared from leg and breast muscle of duck treated by hard scalding and subscalding method and their extractability , ATPase activity , solubility and SDS polyacrylamide gel electrophoresis were compared. The extractability of actomyosin in leg and breast muscle of duck by hard scalding was 7.84 and 39.84mg/g, whereas 4.79 and 28.04mg/g by subscalding respectively. Ca-ATPase activity of breast muscle wash higher than that of leg muscle. In case of leg muscle, hard scalding was higher tan subscalding. Breast muscle showed that subscalding was higher than hard scalding in less than ionic strength 0.08, and was lower than hard scalding in over ionic strength 0.08.Mg-ATPase was great in ionic strength and subcalding was relatively higher than hard scalding. Without regard to be treated method and part, the start point and end point of solubility were like. Hard scalded muscle and breast muscle showed that proteins in thin filament produced many extraction.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.167-173
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• 1997

Everted membrane vesicles of Helicobacter pylori were prepared and the membrane-resided ATPases were characterized. For comparison, Escherichia coli membrane ATPases and hog gastric mucosal H,K-ATPase were employed. ATPase assay revealed that the composite enzyme pool was relatively low in specific activities, below 1/10 times than that found in E. coli. According to their inhibitory specificities, most of the ATPase pool appeared to belong to the P-type ATPase, sensitive to vanadate but not to azide. The enzyme pool was extraordinarily resistant against treatment by N,N'-dicyclohexylcarbodiimide (DCCD). Certain monovalent cations, e.g., $K^+$ or $NH_4^{+}$ stimulated the whole enzyme pool only in the presence of $Mg^{2+}$. On the contrary, $Ni^{2+}$ and $Zn^{2+}$ increased enzyme activity rather effectively without the aid of $Mg^{2+}$. Under a defined condition employed, H. pylori cells could retain the membrane ATPase pool to the extent of $17{\%}$ at pH 3.2. Moreover, its activity was most stable in acidic conditions (pH 5.4-6.4). However, cytoplasmic or peripheral ATPase pools were hardly detected under acidity (below pH 4.6).

• 한국유가공학회:학술대회논문집
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• 1997.05a
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• pp.23-34
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• 1997

Calcium-stimulated ATPase ($Ca^{2+}$-ATPase) which has optimal pH value at 7.0 was found in the membrane fraction of human milk, and its enzymatic properties were studied. The purified $Ca^{2+}$-ATPase required 0.45 mM Ca ion for maximal activity. Among the nucleosides, $Ca^{2+}$-ATPase showed a higher substrate specificity to ATP and UTP than to CTP and GTP. $Ca^{2+}$-ATPase had apparent Km value of 0.065, and V max of 7.63 mol ATP hydrolyzed/mg pro-tein per min, respectively. $Ca^{2+}$-ATPase was potently inhibited by lanthanide, vanadate, and p-chloromercuribenzoate, and inactivated by EDTA, and CDTA and EGTA, but were unaffected by N-ethylmaleimide, $NaN_3$, ouabain, or oligomycin, and was completely inactivated by heating at $60^{\circ}C$ for 10 min. This enzyme activity was concentrated in the membrane fraction of the cream and skim milk membrane, but not founded in bovine milk.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.725-732
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• 1998

In order to elucidate the molecular mechanism of the intracellular $Ca^{2+}$ overload frequently reported from diabetic heart, diabetic rats were induced by the administration of streptozotocin, the membrane vesicles of junctional SR (heavy SR, HSR) were isolated from the ventricular myocytes, and SR $Ca^{2+}$ uptake and SR $Ca^{2+}$ release were measured. The activity of SR $Ca^{2+}-ATPase$ was $562{\pm}14$ nmol/min/mg protein in control heart. The activity was decreased to $413{\pm}30$ nmol/min/mg protein in diabetic heart and it was partially recovered to $485{\pm}18$ nmol/min/mg protein in insulin-treated diabetic heart. A similar pattern was observed in SR $^{45}Ca^{2+}$ uptakes; the specific uptake was the highest in control heart and it was the lowest in diabetic heart. In SR $^{45}Ca^{2+}$ release experiment, the highest release, 45% of SR $^{45}Ca^{2+}$, was observed in control heart. The release of diabetic heart was 20% and it was 30% in insulin-treated diabetic heart. Our results showed that the activities of both SR $Ca^{2+}-ATPase$ and SR $Ca^{2+}$ release channel were decreased in diabetic heart. In order to evaluate how these two factors contribute to SR $Ca^{2+}$ storage, the activity of SR $Ca^{2+}-ATPase$ was measured in the uncoupled leaky vesicles. The uncoupling effect which is able to increase the activity of SR $Ca^{2+}-ATPase$ was observed in control heart; however, no significant increments of SR $Ca^{2+}-ATPase$ activities were measured in both diabetic and insulin-treated diabetic rats. These results represent that the $Ca^{2+}$ storage in SR is significantly depressed and, therefore, $Ca^{2+}-sequestering$ activity of SR may be also depressed in diabetic heart.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.151-159
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• 1997

In order to compare and examine the general characteristics of myofibrillar proteins which is an important protein source as a food resource and relates directly with muscle contraction, we have extracted the myofibrillar proteins from squid and clam. The ionic strength of myofibrillar proteins connected with Ca-ATPase activity, Mg-ATPase activity and EDTA-ATPase activity showed distinct differences between squid and clam. In the activity-pH curve, actomyosin of the clam had a weak biphasic response. In the low concentration of dioxane, myofibrillar proteins of the squid showed a sudden decrease in activity but myofibrillar proteins of the clam showed in increase in activity. Ethanol and metanol in low concentration caused myosin and HMM from the squid and clam to increase their activities. If we cause modification by NEM, under 10-6M concentration, the activity was increased but above 10-5M concentration, there was a sudden decrease in activity.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.102-108
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• 2002

In order to investigate the mechanism of growth inhibition by salt stress, lettuces were grown hydroponically in three different nutrient solutions, normal and 30 mM or 50 mM $KNO_3$-added nutrient solutions, and the electrical conductivities of these solutions were 1.0, 4.5, and 6.5 dS/m, respectively. The activities of plasma and vacuolar $H^+$-ATPases in the root tissue of lettuce were measured by specific inhibitors, 100 ${\mu}M$ vanadate and 50 mM $NO_3^-$, respectively. Microsomal ATPase activity of lettuce grown in the normal nutrient solution was $356\pm1.5$ nmol/min/mg protein. When lettuces were grown in 30 mM and 50 mM $KNO_3$-added nutrient solutions, total activities of microsomal ATPases were increased by 1.6 and 1.9 times, respectively, and the increases were mainly mediated by vacuolar $H^+$-ATPase. These results show that lettuces adapt themselves to salt-stressed condition by increasing the activities of $H^+$-ATPases. Effects of various heavy metal ions were investigated on the microsomal ATPases and various metal ions at 100 $\mu M$ inhibited the activities by 10$\sim$25%. $Cu^{2+}$ showed the highest inhibitory effect on the vacuolar $H^+$-ATPase. These results suggest that lettuce increases the activities of root ATPases, specially that of vacuolar $H^+$-ATPase, in salt-stressed growth conditions and $Cu^{2+}$ could be a useful tool to control the activity of vacuolar $H^+$-ATPase.