• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.148-149
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• 1998

It has been known that potassium channel openers are a new class of molecules that have attracted general interest because of their potent antihypertensive activity in vivo and vasorelaxant activity in vitro (Hamilton and Weston, 1989). In the present study, it was attempted to examine the effect of the potassium channel opener on catecholamine (CA) secretion evoked by cholinergic stimulation, membrane depolarization and calcium mobilization from the isolated perfused rat adrenal gland. The perfusion of pinacidil (30-300 uM) into an adrenal vein for 20 min produced relatively dose-dependent inhibition in CA secretion evoked by ACh (5.32 mM), high $K^{+}$ (56 mM), DMPP (100 uM for 2 min), McN-A-343 (100 uM for 2 min), cyclopiazonic acid (10 uM for 4 min) and Bay-K-8644 (10 uM for 4 min). Also, under the presence of minoxidil (100 uM), which is also known to be a potassium channel activator, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly depressed. However, in adrenal glands preloaded with pinacidil (100 uM) under the presence of glibenclamide (1 uM), an antidiabetic sulfonylurea that has been shown to be a specific blocker of ATP-regulated potassium channels (for 20 min), CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were considerably recovered to a considerable extent of the normal release as compared to that of pinacidil only. These results, taken together, suggest that pinacidil cause the marked inhibition of CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by membrane depolarization, indicating strongly that this effect may be mediated by inhibiting influx of extracellular calcium and release in intracellular calcium in the rat adrenomedullary chromaffin cells. Furthermore, these findings suggest strongly that these potassium channel openers-sensitive membrane potassium channels also play an important role in regulating CA secretion.

• Nutrition Research and Practice
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• v.12 no.5
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• pp.443-448
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• 2018

BACKGROUND/OBJECTIVES: This study was conducted to investigate the effects of sodium-potassium ratio on insulin resistance and sensitivity in Korean adults. SUBJECTS/METHODS: Subjects were 3,722 adults (1,632 men and 2,090 women) aged 40-69 years participating in the Korean genome and epidemiology study_Ansan and Ansung study. Insulin resistance was assessed using homeostasis model assessment of insulin resistance (HoMA-IR) and fasting insulin, and insulin sensitivity was assessed by using the quantitative insulin sensitivity check index (QUICKI). The 24-h urinary sodium and potassium excretion were estimated from spot urinary samples using the Tanaka formula. The generalized linear model was applied to determine the association between urinary sodium-potassium ratio and insulin resistance. RESULTS: HoMA-IR (P-value = 0.029, P-trend = 0.008) and fasting insulin (P-value = 0.017, P-trend = 0.005) levels were positively associated with 24-h estimated urinary sodium-potassium ratio in the multivariable model. QUICKI was inversely associated with 24-h estimated urinary sodium-potassium ratio in all models (P-value = 0.0002, P-trend < 0.0001 in the multivariate model). CONCLUSION: The present study suggests that high sodium-potassium ratio is related to high insulin resistance and low insulin sensitivity. Decreasing sodium intake and increasing potassium intake are important for maintaining insulin sensitivity. Further studies are needed to confirm these findings in longitudinal studies.

• Korean Journal of Community Nutrition
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• v.21 no.6
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• pp.558-573
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• 2016

Objectives: The purpose of this study was to evaluate the main sources of dietary sodium and potassium intake in Koreans by gender, age and regions. Methods: We used the data from 2010-2012 KNHANES. A total of 20,387 subjects aged 8 years and older were included. Intakes were compared by gender, age (8-18, 19-49 and >50 years) and geographical regions in Korea. Dishes were classified into 28 dish groups based on cooking methods. Statistical analysis was performed by using the SAS 9.3 and SUDAAN 11.0.1 software. Results: The mean sodium intake of Koreans was $4866.5{\pm}35.9mg/day$, which was 2.4 times higher than the adequate intake (AI) of sodium for Koreans. We found that daily sodium intakes were significantly different by age, gender and regions. Men and aged over 50 years had significantly higher sodium intake than women and other age groups. The mean potassium intake in Koreans was $3002.2{\pm}19.4mg/day$ and daily potassium intakes were significantly different by age, gender and regions. Women and age 50 years and over had significantly higher potassium intakes than men and other age groups. The average Na/K ratio was $2.89{\pm}0.01$ and was highest in men and in the age group of 19-49 years. The major sources of dietary sodium were soup and stew, followed by Kimchi, noodles and dumpling, pickled vegetables and seasonings, which represented 63.1 % of total sodium intakes. Soup and stew or Kimchi were the primary sources of dietary sodium intake. The major sources of dietary potassium were cooked rice, followed by soup and stew, Kimchi, fruits and beverages. Conclusions: Sodium and potassium intakes and the major sources of those were significantly different by gender, age groups and regions. Therefore, different approaches based on gender, age and regions are needed to decrease sodium intake and increase potassium intake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.538-545
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• 1991

This study measured the daily intake and excretion of sodium and potassium of eight 20-26years old college men during four weeks by means of analyzing their food intake, urine and feces, keeping their normal living pattern and body weight. This study also compared the actual measurement value of sodium and potassium intake by atomic absorption spectrophotometer with the conversion value of them by food table. The results are as follows ; Daily mean sodium intakes conversed ($2.36{\pm}0.03g/day$) was about 63% lower than those intakes meansured($6.36{\pm}0.13g/day$). Daily mean potassium intakes conversed($1.71{\pm}0.03g/day$) was not different of sodium and potassium were $5.49{\pm}0.19g/day\;and\;1.33{\pm}0.08g/day$, respectively. Daily mean fecal excretions of sodium and potassium were $0.24{\pm}0.02g/day\;and\;0.45{\pm}0.03g/day$, respectively. Mean prooportion of Na/K in urine was $4.3{\pm}0.1$.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.436-441
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• 2009

The experiment was conducted to investigate the effect of nitrogen and potassium sources on growth and yield of strawberry 'Seolhyang' and 'Maehyang' in fertigation culture. The plant fresh and dry weight were higher in urea + potassium sulfate and ammonium sulfate + potassium sulfate as nitrogen and potassium sources than others in both varieties. But there were no significant difference among nitrogen and potassium sources in other growth characteristics, such as plant height, no. of leaf, crown diameter etc. Also, the marketable yield of fruit were higher in urea + potassium sulfate and ammonium sulfate + potassium sulfate in 'Seolhyang' than other treatments. 'Maehyang' was better in both treatments but there was no significant difference. The fruit qualities, such as total soluble solid, hardness, acidity, vitamin C content were not significant difference among the treatments. The acidity of soil was tended to decrease but EC was tended to increase highly in ammonium sulfate treatments as a nitrogen source. As above results, the urea and potassium sulfate were recommended as nitrogen and potassium sources for the fertigation culture of strawberry 'Seolhyang' and 'Maehyang'.

• Natural Product Sciences
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• v.4 no.4
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• pp.245-252
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• 1998

The unique sulphated phenolics, gallic acid 3-methyl ether 5-potassium sulphate, isoferulic acid 3-potassium sulphate, and ellagic acid 4,4'-dimethyl ether 3-potassium sulphate have been isolated from the flowers of Tamarix amplexicaulis Ehrenb. (Tamaricaceae). The hitherto unknown natural phenolic acid, gallic acid 3-methyl ether, together with the known phenolic, gallic acid, gallic acid 4-methyl ether, isoferulic acid, ferulic acid, ellagic acid, and ellagic acid 4,4'-dimethyl ether have been also separated and characterized. The structures were established by conventional methods, including electrophoretic analysis and confirmed by ESI-MS, $^1H-\;and\;^{13}C-NMR$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.83-89
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• 1999

Bast fibers of paper mulberry ( Broussonetia Kazinoki Sieb) were cooked with a weak alkaline salt, potassium carbonate which has been known as a major inorganic component of the traditional lye, and its cooking characteristics were investigated . The bast fiber was easily cooked by potassium carbonate. The pulp yield was rapidly decreased up to 20-30 mol of potassium carbonate, but the Kappa number was slowly decreased with increasing of potassium carbonate. The potassium carbonate pulps were easily defibered at low cooking chemical charge of 25mm on and high pulp yield of about 80%. These results were confirmed that pectin was easily removed during the potassium carbonate cooking. In contrast, when sodium carbonate was used as a cooling agent, the bast fiber was only partially defibered. Thus, sodium carbonate was a less effective cooling chemical of the bast fiber. The results of this experiment indicated that potassium carbonate could not only be used as a good cooling agent of bast fiber, but also as an alternative agent of sodium hydroxide.

• Applied Microscopy
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• v.27 no.1
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• pp.31-46
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• 1997

Ultrastructure of mouse thymus was evaluated, following the administration of potassium dichromate and mercuric chloride, the heavy metals of evironmental pollutants. Potassium dichromate (20 mg/kg) or mercuric chloride solutions (10 mg/kg) were subcutanously injected to the mice. Six hours, three days and two weeks after the injections, animals were sacrificed. Thymic tissues were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde solutions. The procedure was followed by the fixation in 1% osmium tetroxide solutions. Washed and dehydrated tissue-blocks were embedded in the araldite mixture. Ultra-thin sections were stained with uranyl acetate-lead citrate solutions. Results observed were as follows: 1. In electron microscopy, cortical population of thymocytes in the thymus of experimental groups were reduced. especially in the outer cortex. Subcapsular cortices of potassium dichromate treated mice were filled with many epithelial reticular cells, whereas the similar area of mercuric chloride-treated mice exhibited large intercellular spaces. 2. In the thymus of mercuric chloride treated group, large intercellular spaces were formed by shrinkage of epithelial reticular cells, and the space was invaded by numerous cytoplasmic projections of macrophages. Thymocytes nuded out from the shrunken cytoplasm of epithelial reticular cells, presented numerous microvilli. 3. In the thymus of potassium dicromate treated group, many activated macrophages and plasma cells migrated into thymic cortices. 4. In the perivascular spaces of thymic cortices of potassium dichromate- and mercuric chloride-treated mice, activated macrophages. plasma cells, collagen fibrils, and flocculent substance of exudated materials were exhibited. From the above findifgs, it was concluded that potassium dichromate or mercuric chloride could disturb the normal differentiation or 'education' of T cells in the thymic cortex. In turn, these heavy metals may hurt the immunological defense mechanism.

• YAKHAK HOEJI
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• v.30 no.3
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• pp.143-148
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• 1986

The effect of orally administered ginseng ethanol extract on potassium deficient and normal rat skeletal muscles was investigated in terms of Ca uptake by sarcoplastic reticulum fragments. The ginseng ethanol extract (100mg/kg/day) was administered orally to Sprague-Dawley rats for 21 days and their changes of body weights, $K^+$ content in skeletal muscles, and calcium uptake capacity of sarcoplamic reticulurn of each groups were measured. The growth rate of rats fed with the potassium deficient diet was significantly decreased compared to that of normal rats. Ginseng components did not show any effect on the decreased growth rate of the postassium deficient rats. Potassium content in skeletal muscle from potassium deficient rats was significantly reduced compared to that of normal rats. Ginseng components showed the tendency to prevent the reduction in potassium content of potassium deficient rats, but differences were not statistically significant. Calcium uptake of SR prepared from skeletal muscles of potassium deficient rats was increased significantly compared to that of normal rats. Ginseng components prevented such increase of calcium uptake by 30%. In summary, it can be concluded that ginseng may prevent the increase in Cauptake of SR obtained from potassium deficient rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.534-538
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• 1992

This study was carried out to investigate the effect of potassium sorbate on the growth of yogurt starter and contaminant yeast. Yogurt starter was isolated using 9 company of market yogurt and 10 strains of contaminant yeast was isolated in swollen yogurt after incubated for 7 days at $25^{\circ}C.$ The growth of isolated starter was inhibited by 0.3% of potassium sorbate except starter-H. Most isolated yeast was inhibited by the 0.1% of potassium sorbate. The growth of yeast-9 was the most inhibited among isolated yeast. The growth of selected starter-H was similiar to that of control in MRS broth containing 0.3% of potassium sorbate. 0.3% of potassium sorbate did not affect the growth of selected starter-H incubated with selected yeast-9 in skimmilk at $37^{\circ}C$ for 48hr, whereas, the growth of yeast-9 did not occur during incubation. The viable cell change of starter-H in yogurt contaminated with selected yeast-9 was not observed at $4{\pm}1{\circ}C$ for 7 days and the contaminant inhibited in 0.3% potassium sorbate containing yogurt during storage at $25^{\circ}C.$