• Journal of Nutrition and Health
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• 제35권7호
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• pp.754-762
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• 2002

This study was performed to investigate the effect of sodium intake on blood pressure and blood parameters. 20 young adult women were fed the diets containing 290.5 mEq (high-Na diet) and 51.3 mEq (low-Na diet) Na for 6 days, respectively. BMI, DBP, and MBP were significantly lower in low-Na diet than those in high-Na diet. 20 subjects were divided into 3 groups according to the salt-sensitivity. In salt-sensitive group, decreases in SBP, DBP, and MBP by low-Na diet were shown. And there were not significant difference in blood pressure of salt-resistant group between high- and low-Na diet. In count-reactive group, MBP in low-Na diet was significantly higher than that in high-Na diet. Hemoglobin, creatinine, uric acid, and haptoglobin levels in serum were significantly higher in low-Na diet than those in high-Na diet. Among groups with different salt-sensitivity, increments of haptoglobin by low-Na diet were shown in salt-sensitive and counter-reactive groups. Actually, low sodium diet affects not only the blood pressure, but other biochemical parameters which in turn affect an individual overall health. Also salt-sensitivity should be considered as an important determinant. Therefore, for the patients who need restricted Na diet, it would be suggested that various biochemical changes and individual salt-sensitivity should be carefully considered along with dietary Na manipulation.

• Journal of Nutrition and Health
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• 제33권4호
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• pp.403-410
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• 2000

The effects of dietary Ca and Na levels on lipid metabolism in hyper lipidemic/hypercholesterolemic rats were examined. In Expt. 1, normal rats were divided into six groups and fed high fat(15%, w/w)/cholesterol(1%, w/w) diet containing two levels of Na, low (0.05) or high(1.5%) and three levels of Ca, low(0.1%), normal (0.5%), or high(1.5%) for 8 weeks. In Expt. 2, hyperlipidemia / hypercholesterolemia rats were induced by feeding high fat / cholesterol diet for 4 weeks. They were divided into four groups and fed the high fat / cholesterol diet, containing two levels of Na, low or high and two levels of Ca, low or high for 4 weeks. In Expt. 1, total lipid and total cholesterol contents in serum and liver were significantly lower in rats fed high Ca diet than in rats fed normal or low Ca diet regardless of dietary Na levels. Serum TG was the highest in rats fed low Ca and low Na diet. In Expt. 2, Serum total lipid, TG, and total cholesterol levels decreased by 24, 35, 26% respectively in rats fed high Ca diet regardless of dietary Na levels. Serum total lipid level tended to increased in rats fed low Na diet. The total lipid and TG contents in liver slightly decreased in rats fed high Ca diet. Another observation was that high Ca intake significantly faciliated the fecal lipid and cholesterol excretion regardless of dietary Na levels. There results suggest that the hypolipidemidc/hypocholesterolemic effects of high Ca diet could be partly due to increase in lipid and cholesterol excretion and these effects may be independent of dietary Na levels.

• Journal of Nutrition and Health
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• 제37권2호
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• pp.108-114
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• 2004

This study was performed to determine the effect of dietary Na levels on plasma amino acid levels. Plasma amino acid levels were compared in 20 adult healthy women subjects who were given high Na diet (290.48 mEq/day : NaCl 17g) or low Na diet (51.26 mEq/day : NaCl 3g) for subsequent 6 days. Plasma essential amino acids levels were significantly decreased (36%) while plasma non-essential amino acids levels were significantly increased (22%) when subjects were given low Na diet (p＜0.001). Among essential amino acids, threonine was decreased (74%) significantly when subjects were given low Na diet (p＜0.01). Among nonessential amino acids, serine (49%), proline (20%) and aspartic acid (14%) were increased (p＜0.01), while arginine (48%) and glutamic acid (27%) were decreased (p＜0.001). In conclusion, dietary Na contents seemed to be an important factor to affect plasma amino acid levels. It would be appropriate to decrease the dietary Na intakes level considering the various clinical effects of dietary Na on the body fluid. For the patients who need low Na diet, it would be suggested that the level of dietary proteins should be carefully considered along with dietary Na manipulation. (Korean J Nutrition 37(2) : 108-114, 2004)

• 한국식품영양과학회지
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• 제31권6호
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• pp.1035-1042
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• 2002

본 연구는 나트륨 섭취수준이 혈중 지질과 혈당에 미치는 영향을 규명해보기 위하여 정상 성인 여성 20명을 대상으로 고나트륨식과 저나트륨식을 각각 6일씩 공급한 후 혈중 지질, 혈당 및 기타 혈액성상의 변화를 비교분석하였다. 그 결과를 요약하면 다음과 같다. 연구대상자들의 평균연령은 22.9$\pm$2.5세였으며 평균 체중과 신장은 54.7$\pm$6.6kg과 160.0$\pm$4.8cm였고 수축기/이완기 혈압은 110.3$\pm$7.7/67.5$\pm$9.7 mm Hg로 정상범위에 속하였다. 나트륨 섭치수준에 따른 평균 체중의 변화는 고나트륨식이 54.7$\pm$6.4 kg으로 저나트륨식의 53.8$\pm$6.2 kg보다 유의하게 높았다(p<0.001). 평균 신장은 고나트륨식과 저나트륨식간에 유의한 차이가 없었으나, 이완기혈압은 고나트륨식(65.5$\pm$8.3 mmHg)보다 저나트륨식(60.8$\pm$8.6 mmHg) 이후 유의하게 감소하였다(p<0.05). 혈청 콜레스테롤,LDL-콜레스테롤,HDL-콜레스테롤 함량은 나트륨 섭취 수준에 따라 유의적인 차이를 보이지 않았으나 중성지질은 고나트륨식의 89.4$\pm$27.3 mg/dL보다 저나트륨식이시 73.8$\pm$12.5mg/dL로 유의하게 감소하였다(p<0.05). 혈청 아포 A-I은 고나트륨식의 183.7$\pm$32.7 mg/dL보다 저나트륨식에서 167.5$\pm$22.8 mg/dL로 유의적으로 감소하였으나(p<0.001), 아포 B는 고나트륨식의 83.3$\pm$13.9 mg/dL보다 저나트륨식에서 90.8$\pm$12.9 mg/dL로 유의하게 증가하였다(p<0.001). 아포 A-I/B는 저나트륨식이 1.9$\pm$0.2로 2.2$\pm$0.3을 보인 고나트륨식보다 유의하게 낮았으나(p<0.001),AI(atherogenic index)는 나트륨 섭취수준에 의한 영향을 받지 않았다 혈액 응고시간으로 thrombin time과 Prothrombin time은 저나트륨식이 각각 9.6$\pm$1.1초, 11.6$\pm$0.7초로 나타나 고나트륨식의 11.3$\pm$1.3초, 12.0$\pm$0.4초보다 유의하게 빠른 것으로 나타났다(p<0.001, p<0.05). 나트륨 섭취수준에 따른 혈당 농도는 고나트륨식과 저나트륨식 간에 유의한 차이가 없었으나, 인슐린 함량은 저나트륨식이 10.3$\pm$5.0 $\mu$IU/mL로 고나트륨식의 6.0$\pm$2.6$\mu$IU/mL보다 유의하게 높았다.(P<0.01). 이상의 결과를 종합할 때 저나트륨식에서 이완기 혈압, 혈청 중성지질, 아포A-1, 혈액 응고시간은 감소되었으나, 혈청 아포 B와 인슐린함량은 유의하게 증가되어 지속적인 저나트륨식 처방시 지질과 당질대사의 변화를 초래할 가능성이 있는 것으로 보여진다. 따라서 혈압 저하를 목적으로 하는 나트륨 제한식의 실시는 다양한 체내의 생화학적 변화를 고려해서 이루어져야 할 것이며, 앞으로 이에 대한 보다 다각적인 연구가 요구된다.

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

• Journal of Nutrition and Health
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• 제35권8호
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• pp.840-847
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• 2002

This study explored the effect of dietary levels of Na and Ca on spontaneously hypertensive rats (SHR). SHR were randomly divided into 5 groups and fed a high fat/cholesterol diet containing three levels of Na (0.05, 0.1, 1.5%) and Ca (0.1, 0.5, 1.5%) for 9 weeks. Body weight gain was not influenced by dietary intake but water intake significantly increased in high Na supplementation. Systolic blood pressure was not influenced by dietary Na and Ca levels but was decreased by dietary low Na/high Ca levels at 9 weeks. Angiotensin-II level was affected by dietary Na level but not by Ca levels. Plasma Ca, Mg, K and Na levels were in the normal range regardless of dietary Na and Ca levels. Weight, and K and Na contents of the heart and kidney were not significantly different among those with different dietary Na and Ca levels. Ca and Mg contents of the heart and kidney were significantly higher in the normal Na/normal Ca group. Ca and Mg in the feces were higher in those with high Ca intake. Na in the feces was higher in those with high Na intake. Therefore, Na and Ca had different mechanisms in the hypertension/hyperlipidemia models, respectively. And we suggested that Mg must be supplemented when Ca intake was high because Mg excretion was increased by Ca supplementation.

• The Korean Journal of Physiology
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• 제25권1호
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• pp.69-79
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• 1991

To evaluate the acute and chronic effects of potassium on aldosterone response to different amounts of sodium intake, two series of experiments were conducted. In the first series of experiments, when the plasma K level was increased acutely by KCI infusion $(20\;{\mu}g/kg/min\;for\;20 min)$, plasma aldosterone concentration increased in both low Na and high Na groups. However, the aldosterone response to K infusion was significantly greater in the low Na than in the high Na groups. In the second series of experiments, rats fed a high K diet chronically showed a significantly higher plasma K level than those fed a low K diet. However, plasma Na level was maintained relatively constant independent of the Na intake. Both the plasma renin activity (PRA) and aldosterone levels were inversely related to the Na intake. There was a highly positive correlation between aldosterone level and PRA over a wide range of sodium intakes. However, the slope of the correlation line was distinctly steeper in the K-repleted than in the K-depleted rats. The above results indicate that the adrenotropic action of acute K load was augmented in the presence of high plasma renin levels. However, when plasna K level was elevated chronically by a high-K diet, aldosterone secretion was markedly stimulated, although the plasma lenin levels were suppressed.

• Nutrition Research and Practice
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• 제10권3호
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• pp.288-293
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• 2016

BACKGROUND/OBJECTIVES: We compared changes in heart-femoral pulse wave velocity (hfPWV) in response to low sodium and high sodium diet between individuals with sodium sensitivity (SS) and resistance (SR) to evaluate the influence of sodium intake on arterial stiffness. SUBJECTS/METHODS: Thirty-one hypertensive and 70 normotensive individuals were given 7 days of low sodium dietary approach to stop hypertension (DASH) diet (LSD, 100 mmol NaCl/day) followed by 7 days of high sodium DASH diet (HSD, 300 mmol NaCl/day) during 2 weeks of hospitalization. The hfPWV was measured and compared after the LSD and HSD. RESULTS: The hfPWV was significantly elevated from LSD to HSD in individuals with SS (P = 0.001) independently of changes in mean arterial pressure (P = 0.037). Conversely, there was no significant elevation of hfPWV from LSD to HSD in individuals with SR. The percent change in hfPWV from the LSD to the HSD in individuals with SS was higher than that in individuals with SR. Subgroup analysis revealed that individuals with both SS and hypertension showed significant elevation of hfPWV from LSD to HSD upon adjusted analysis using changes of the means arterial pressure (P = 0.040). However, there was no significant elevation of hfPWV in individuals with SS and normotension. CONCLUSION: High sodium intake elevated hfPWV in hypertensive individuals with SS, suggesting that high sodium intake increases aortic stiffness, and may contribute to enhanced cardiovascular risk in hypertensive individuals with SS.

• Journal of Nutrition and Health
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• 제30권8호
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• pp.920-929
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• 1997

This study examined the effect of dietary salt levels on the incidence and cure of gastric ulcer in rats. Two sets of experiment were conducted . In the first experiment, the rats were divided into 3 groups. The 3 groups were fed 0%, 4%, and 8% NaCl diets respectively for 20days. The rats were given water -immersion restraint stress at the end of the dietary period , and sacrificed. The ulcer index by histological test was higher in rats fed the 8% NaCl diet than those in the other groups. The hexosamine and glutathione levels were significantly lower in the rats fed the 8% NaCl diet. Hematocrit and total iron binding capacity(TIBC) showed lower values caused by bleeding of gastric mucosa. The second experiment was designed to determine the effect of soldium concentration on the cure of gastric ulcer . As the gastric ulcer was recovered, ulcer length was gradually deceased in the control group but not changed in the 8% NaCl diet group. The gastric hexosamine and hepatic glutathione were increased in the control group but decreased in the 8% NaCl diet group. The hematologic indices of stressed rats showed the same tendency. As a result, dietary salt per se did not cause gastric ulcer . Once an ulcer is formed by stress or any other factor, higher levels of dietary salt may be detrimental to gastric mucosa, thereby delaying the healing of the ulcer. It is recommended that dietary salt intake be reduced in stress-prone people.

• Journal of Nutrition and Health
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• 제29권10호
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• pp.1096-1104
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• 1996

This study was performed to evaluate the effect of sodium cholride supplementation on bone metabolism in female rats consuming a low calcium diet. Twenty five female rats were divided into three dietary groups (control Na : 0.1038%, 1% Na : 1.036%, 2% Na : 2.072%). All experimental diets contained 0.27% Ca and were fed to rats with deionized water for 7 weeks. Bone mineral density(BMD) and bone mineral content(BMC) of total body, spine and femur were measured using energy x-ray absorptiometry(DEXA) by small animal software. Then Ca efficiency was calculated from BMD and BMC. Serum Ca, P, Na and urine Ca, P, Na were determined. Urinary pyridinoline, serum ALP were measured to monitor bone resorption. Following 7 weeks, sodium cholride supplemented groups had higher urinary Ca excreteion, urinary pyridinoline, crosslinks value and serum ALP. There was no significant difference in case of serum Ca among all groups. Sodium chloride supplemnted groups had lower Ca effciency of total, spine and femur BMD and BMC than that of control group. In conclusion high salt intake not only increases urinary Ca excretion as urinary Na excretion does but also increase bone resorption and decrease Ca efficiency of each bone. It is been suggested that high salt intake may be harmful for bone maintenance. Therfore, the decrease of salt intake to the level of recommendation would be desirable.