• Journal of Nutrition and Health
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• 제26권8호
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• pp.915-924
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• 1993

To study the effect of menopause and dietary protein level on Ca metabolism, ovariectomy (OVAX) and sham operations were performed in 16-week old female rats. Each treatment group was fed for 16 weeks either 5%(L) or 50%(H) casein diets, forming SH, SL, OH, OL groups. High protein groups(SH, OH) showed higher Ca and hydroxyproline excretion in urine. Urinay hydroxyproline was also higher in OVAX, which tells the possibility of increased bone resorption by OVAX and by high dietary protein. At 16th wee, however, urinary Ca and hydroxyproline of SH caught up with OH group, whereas those of OL remained higher than SL. Therefore it seems that high dietary protein overrides the effect of OVAX with time. Urnary protein measured at 8th week was higher in high protein groups, especially in OH. GFR was not differ significantly among groups at 8th week. At 16th week, however, high protein groups showed twice the GFR value of low protein groups. Therefore the increase of urinary Ca and hydroxyproline in SH and OH groups can be explained partly by the increased GFR. The tendency of increased GFR and urinary excretion of protein, Ca, and hydroxyproline was most obvious in OH group. It seems that the effect of high protein diet is likely to accelerated by ovariectomy. The effect of Ovax and dietary protein on the composition of femur, scapular, and lumbar bones, was not pronounced. However, when only the high protein groups were compared, OVAX resulted in the reduction of bone weight, ash and Ca contents, especially in femur. The reason that was no significant effect on bone might be due to the short experimental period to induce that was no significant effect on bone might be due to the short experimental period to induce the changes on bone composition and dietary Ca content used in this experiment may have been high enough to prevent bone loss.

• Journal of Nutrition and Health
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• 제31권4호
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• pp.716-728
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• 1998

To investigate the effect of dietary Ca levels on metabolic changes of Ca and skeleton in postmenopausal women, 10-month-old ovariectomized female rats were compared with 2 month old rats. The rats were fed either 0.2% or 1.2% Ca diets for 16 weeks. Food intake and weight gain as higher in rats fed high Ca diets and in ovariectomized rats. Apparent Ca absorption as higher, and Ca balance was lower in the low Ca groups. Vertebrae density was higher in old rats or those fed a high Ca diets. The old rats and ovariectomized rats showed decreased bone formation, increased bone resorption and kidney function deterioration resulting in increased urinary Ca excretion. Contradictory to the above observation, old rats and ovariectomized rats still showed higher bone mass and bone ash content. Therefore aging was not fully onging in 10-month-old rats. Bone weights, mineral contents, and mineral/wt ratio were lower in ovariectomized rats. Dietary Ca level did not affect urinary Ca excretion, urinary protein excretion, GFR, serum alkaline phosphatase, or urinary hydroxyporline excretion. This means that dietary Ca level did not influence kidney function or bone turnover. However Ca content and the ash content of femur, 4th vertebra, and scapula were increased in high Ca groups. Therefore, it is considered that decreased bone formation and accelerated bone resorption may account for the increased osteoporotic risk in women in menopause after middle age. However, Ca metabolism can be improved and bone components can be maintained if Ca is supplemented.

• 한국식품영양과학회지
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• 제30권4호
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• pp.657-661
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• 2001

이소플라본 보충이 골다공증의 예방 및 치료에 미치는 영향을 관찰하고자 Sprague-Dawley 암컷을 수술없이 일반식이를 제공한 군(CON), sham-operation 후 일반식이를 제공한 군(SH), 난소절제한 뒤 일반식이를 제공한 군(OVX), 난소절제 후 isoflavone을 공급한 군(OL, OM, OH)으로 나눈 뒤, 난소절제 4일 및 8주 후부터 8주간 이소플라본을 공급하여 혈액의 ALP, sy 중의 hydroxyproline의 변화, 골밀도, 골강도 및 골무게 등을 연구하였다. 골다공증의 예방에 대하여 isoflavone의 효과를 관찰한 결과, ALP는 난소를 절제한 OVX군에서는 CONrns과 SH군에 비해 유의적으로 높은 값을 보였다. 그러나, 난소절제 후 4일부터 8주간 isoflavone을 보충시킨 결과 ALP 활성과 urinary hydroxyproline 함량은 SH군과 비슷하게 낮아졌다. 특히 OM(0.8mg/kg diet)군의 경우 ALP활성과 urnary hydroxyproline 함량이 가장 낮아서 OVX군과 유의적인 차이를 보였다.(p<0.05). 난소적출 후 8주 후에 골밀도를 측정한 결과 난소절제군의 골밀도가 CONrns과 SH군에 비해 유의적으로 낮은 것으로 나타났다. Isoflavone을 보충한 결과 골밀도가 증가하였으나 유의적인 차이는 없어다. 골다공증의 치료효과에 대한 연구결과 alkaline phosphatase activity의 감소, 골밀도, 골강도 및 골무게가 증가하였으나 유의적인 차이는 나타나지 않았다. 이상의 결과는 난소절제 후에 일어나는 골격 대사의 이상은 isoflavone을 보충시킴으로써 어느 정도 정상화시킬 수 있음을 시사한다. 따라서 적절한 양의 isoflavone 보충은 폐경 후 여성의 골대사에 유익한 효과를 줄 것으로 풀이된다.