藏红花提取液对去卵巢大鼠骨密度及骨代谢生化指标的影响

目的：研究中药藏红花提取液对去卵巢大鼠股骨骨密度及血清骨代谢生化指标的影响。方法：选用48只4月龄SD雌性大鼠,随机分为6组：假手术组、模型组、戊酸雌二醇组、藏红花低、中、高剂量组。术后4周各组分别给予相应制剂灌胃,术后12周处死,分别测定股骨骨密度、子宫指数、雌二醇、血钙、血磷、碱性磷酸酶。结果：与模型组相比,藏红花各剂量组股骨骨密度明显升高（p〈0.01）,雌二醇测定值升高（p〈0.01）,碱性磷酸酶显著降低（p〈0.01）,血钙及血磷无统计学差异（p〉0.05）;与戊酸雌二醇组比较,藏红花各剂量组子宫指数显著降低（p〈0.01）。结论：藏红花提取液有助于抑制去卵巢大鼠骨量的丢失,改善骨代谢,对骨质疏松症具有防治作用。     

Magnesium Supplementation did not Affect the Increasing Bone Zinc Concentration in Rats Given Excess Calcium as Carbonate

We investigated the effect of magnesium supplementation on zinc distribution in rats given excess calcium as carbonate. Rats were given a control diet (5 g/kg calcium and 0.5 g/kg magnesium), a high calcium diet (HC, 25 g/kg calcium and 0.5 g/kg magnesium) or the high calcium diet supplied with magnesium (HCM, 25 g/kg calcium and 2.5 g/kg magnesium) for 4 weeks. Calcium carbonate and magnesium oxide were used for increasing these mineral concentrations in diets. Although feed intake did not differ among the groups, the excess calcium suppressed feed efficiency, irrespective of dietary magnesium concentration. Femoral magnesium concentration was lower in the HC group than in the control and the HCM groups. Femoral zinc concentration was higher in the HC group and the HCM group than in the control group. The zinc concentration in the kidney was lower in the HC group and the HCM group than in the control group. The excess calcium did not affect zinc concentration in plasma and other tissues such as the liver, testis, and spleen, irrespective of dietary magnesium. These results suggest that the increasing bone zinc and the decreasing renal zinc do not result from magnesium insufficiency in rats given excess calcium as carbonate.     

Effect of chitooligosaccharides on calcium bioavailability and bone strength in ovariectomized rats

Chitosan polymer with deacetylation degree of 93% was hydrolyzed with an endo-type chitosanase (35,000 U/g protein) with substrate to enzyme ratio of 1 to 1.5 for 18 h in a batch reactor, and then the resultant hydrolysates were fractionated into four different molecular weights using an ultrafiltration (UF) membrane reactor system. An in vitro study elucidated that four kinds of chitooligosaccharides (COSs) could efficiently inhibit the formation of insoluble calcium salts in the neutral pH. In vivo effects of COSs on Ca bioavailability were further studied in the osteoporosis modeling rats induced by ovariectomy and concurrent low calcium intake. During the experimental period corresponding to the menopause with the osteoporosis disease, calcium retention was increased and bone turnover was decreased by COS IV supplementation in the ovariectomized (OVX) rats. After the low Ca diet, COS IV diet including both normal level of calcium and vitamin D significantly decreased calcium loss in feces and increased calcium retention compared to the control diet. The levels of femoral total calcium, bone mineral density (BMD), and femoral strength were also significantly increased by the COS IV diet in a similar level to those of CPP diet group. In the present study, the results proved the beneficial effects of low molecular chitooligosaccharide (COS IV) in preventing negative mineral balance.     

Silicon Supplementation Improves the Bone Mineral Density of Calcium-Deficient Ovariectomized Rats by Reducing Bone Resorption

The purpose of this study was to investigate the effect of silicon (Si) supplementation on bone mineral density (BMD) and bone metabolism parameters relative to calcium (Ca) intake levels in ovariectomized rats. A total of 72 female Wistar rats (6 weeks) were ovariectomized (OVX) and divided into six groups, and Si (500 mg of Si per kilogram of feed) was or was not administered with diets containing various levels of Ca (0.1%, 0.5%, and 1.5%) for 10 weeks. The groups were as follows: (1) Ca-deficient group (0.1% Ca), (2) Ca-deficient with Si supplementation group, (3) adequate Ca group (0.5% Ca), (4) adequate Ca with Si supplementation group, (5) high Ca group (1.5% Ca), and (6) high Ca with Si supplementation group. Si supplementation significantly increased the BMD of the femur and tibia in Ca-deficient OVX rats, while no change was observed with Si supplementation in the BMD of the spine, femur, and tibia in the adequate and high Ca groups. Serum alkaline phosphatase and osteocalcin levels were not affected by Si supplementation or Ca intake levels. C-telopeptide type I collagen levels were significantly decreased as a result of Si supplementation in Ca-deficient OVX rats. In summary, Si supplementation produced positive effects on bone mineral density in Ca-deficient OVX rats by reducing bone resorption. Therefore, Si supplementation may also prove to be helpful in preventing osteoporosis in postmenopausal women whose calcium intake is insufficient.     

Combined Effects of Phytoestrogen Genistein and Silicon on Ovariectomy-Induced Bone Loss in Rat

This study was performed to evaluate the effect of concomitant supplementation of genistein and silicon on bone mineral density and bone metabolism-related markers in ovariectomized rat. Three-month-old Sprague Dawley female rats were subjected to bilateral ovariectomy (OVX) or sham surgery, and then the OVX rats were randomly divided into four groups: OVX-GEN, OVX-Si, OVX-GEN-Si, and OVX. Genistein and silicon supplementation was started immediately after OVX and continued for 10 weeks. In the OVX-GEN group, 5 mg genistein per gram body weight was injected subcutaneously. The OVX-Si group was given soluble silicon daily in demineralized water (Si 20 mg/kg body weight/day). The OVX-GEN-Si group was given subcutaneous injections of 5 mg genistein per gram body weight, at the same time, given soluble silicon daily (Si 20 mg/kg body weight/day). The results showed that the genistein supplementation in the OVX rats significantly prevented the loss of uterus weight; however, the silicon supplementation showed no effect on the uterus weight loss. The lumbar spine and femur bone mineral density was significantly decreased after OVX surgery; however, this decrease was inhibited by the genistein and/or silicon, and the BMD of the lumbar spine and femur was the highest in the OVX-GEN-Si-treated group. Histomorphometric analyses showed that the supplementation of genistein and/or silicon restored bone volume and trabecular thickness of femoral trabecular bone in the OVX group. Besides, the treatment with genistein and silicon for 10 weeks increased the serum levels of calcium and phosphorus in the OVX rats; serum calcium and serum phosphorus in the OVX-GEN-Si group were higher than those in the OVX-GEN and OVX-Si group (P < 0.05). At the same time, the treatment with genistein and/or silicon decreased serum alkaline phosphatase (ALP) and osteocalcin, which were increased by ovariectomy; serum ALP and osteocalcin in the OVX-GEN-Si group were lower than those in the OVX-GEN and OVX-Si groups (P < 0.05). The results above indicate that genistein and silicon have synergistic effects on bone formation in ovariectomized rats.     

Protective Effects of Gallium, Germanium, and Strontium Against Ovariectomized Osteoporosis in Rats

The effects of trace elements of gallium (Ga), germanium (Ge), and strontium (Sr) on ovariectomized (OVX) osteopenic rats were studied in this paper. The urine calcium content, serum calcium, and phosphorus contents, bone mineral content, mineral dissolution, and mechanical strength of the osteopenic rats were analyzed respectively. After the rats were fed with Ga, Ge, and Sr diet for 8 weeks, respectively, the urine calcium content decreased (P?<?0.01). Plasma calcium and phosphate concentrations decreased in the order of OVX group?>?Ge group?>?Sr group?>?Ga group?>?Sham group. Mineral content increased in the order of OVX group?<?Ge group?<?Sr group?<?Ga group?<?Sham group. A dramatic decrease in calcium solubility was found both in the gallium and strontium treated animals (P?<?0.05). However, the same result did not occur in germanium treated groups. The data provide an important proof of concept that gallium and strontium might be a new potential therapy for the management of postmenopausal osteoporosis in humans.     

阿司匹林对去势大鼠腰椎骨密度及微观结构的影响

目的:研究阿司匹林对去势(卵巢切除)大鼠腰椎骨密度及微观结构的影响。方法:取48只3月龄SD雌性大鼠随机分为6组:去势组(OVX组)、对照组(Sham组)及4个阿司匹林治疗组(Aspirin组),每组8只。OVX组及Aspirin组采用卵巢切除法建立骨质疏松模型。去势后1周,阿司匹林治疗组剂量分别为2.25、4.46、8.92及26.75 mg/kg(A1、A2、A3及A4组),每天灌胃一次,OVX组及Sham组予同等量生理盐水灌胃。灌胃3个月后处死,剖取腰椎椎体,以双能X线吸收骨密度测量仪(DXA)和Micro-CT进行测量分析。结果:DXA分析结果显示:阿司匹林各剂量组BMD值较OVX组有统计学差异(P<0.01)。Micro-CT分析表明:与OVX组比较,阿司匹林各剂量组BV/TV、Tb.Th、Tb.N、BMD均显著性提高(P<0.01),BS/BV、Tb.Sp显著性降低(P<0.01),阿司匹林各剂量组BV/TV、BS/BV、Tb.Th、Tb.N、Tb.Sp、BMD与Sham组相比有统计学差异(P<0.01)。结论:阿司匹林可以改善去势大鼠骨小梁结构,增加骨质密度,对去势大鼠骨质疏松具有防治作用,其作用途径可能包括抑制骨吸收和刺激骨形成两方面。     

Manganese Supplementation Reduces the Blood Cholesterol Levels in Ca-Deficient Ovariectomized Rats

Manganese (Mn) is an essential element for normal development and bodily functions in humans. In the present study, we examined whether Mn supplementation can alter the serum lipid parameters and liver function in Ca-deficient ovariectomized (OVX) rats. Sixty female Sprague–Dawley rats (6 weeks) were divided into five groups and bred for 12 weeks: sham-operated control group (Sham), OVX Ca deficiency group (OLCa) with Ca-deficient diet (0.1% Ca modified AIN-93N diet), OVX Ca deficiency and Mn supplementation group (OLCaMn), OVX with adequate Ca group (OACa; 0.5% Ca AIN-93N diet), and OVX with adequate Ca and Mn supplementation group (OACaMn). A low Ca diet increased the liver weight and serum levels of GOT, GPT, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol in OVX rats. Mn supplementation decreased these parameters in Ca-deficient OVX rat. The results of our study suggest Mn supplementation results in reductions of the blood cholesterol levels, which show an increase due to Ca deficiency in OVX rats.     

Short-term Administration of Water-soluble Silicon Improves Mineral Density of the Femur and Tibia in Ovariectomized Rats

Silicon is important for the proper growth and development of bone and connective tissues. This study was designed to investigate if water-soluble silicon could be used for the treatment of postmenopausal osteoporosis. Silicon (Si 20 mg/kg body weight/day) was administrated orally to 17-week-old ovariectomized (OVX) rats for 4 weeks. Silicon did not alter weight gain in OVX rats. Silicon supplementation significantly increased the bone mineral density of the femur (p < 0.05, vs. OVX control group) and tibia in OVX rats (p < 0.05, vs. OVX control group). Serum alkaline phosphatase and osteocalcin, two bone formation biomarkers tested, were not significantly altered, but urinary calcium and phosphorous excretion tended to decrease with silicon supplementation. OVX rats with silicon supplementation showed a relatively higher serum CTx compared to the nonsupplemented OVX group (p < 0.01, vs. OVX control group). According to these results, short-term soluble silicon supplementation improved bone mineral density in OVX-induced osteoporosis.     

Analysis of Bacteria,Parasites, and Heavy Metals in Lettuce (<Emphasis Type="Italic">Lactuca sativa</Emphasis>) and Rocket Salad (<Emphasis Type="Italic">Eruca sativa</Emphasis> L.) Irrigated with Treated Effluent from a Biological Wastewater Treatment Plant

The purpose of this study was to verify the effect of organic gallium on ovariectomized osteopenic rats. Thirty Wistar female rats used were divided into three groups: (1) sham-operation rats (control), (2) ovariectomized (OVX) rats with osteopenia, and (3) OVX rats with osteopenia treated with organic gallium. Treatments were performed over an 8-week period. At sacrifice, the fifth lumbar vertebral body, one tibia, one femur, and the fourth lumbar vertebrae were removed, subjected to micro-CT for determination of trabecular bone structure, and then processed for histomorphometry to assess bone turnover. The femoral neck was used for mechanical compression testing. Treatment with organic gallium increased bone volume in OVX animals. Organic gallium-treated animals had significant increases in trabecular and cortical thickness and bone strength. The plasma total calcium and inorganic phosphate concentrations in OVX rats decreased and bone mineral content in the lumbar vertebrae and femur increased after treatment with organic gallium. These data provide an important proof of concept that organic gallium may represent a powerful approach to treating or reversing severe osteoporosis in humans.     

Comparison of the Therapeutic Effects of Yeast-incorporated Gallium with those of Inorganic Gallium on Ovariectomized Osteopenic Rats

The purpose of this study was to verify the effect of organic gallium on ovariectomized osteopenic rats. Thirty Wistar female rats used were divided into three groups: (1) sham-operation rats (control), (2) ovariectomized (OVX) rats with osteopenia, and (3) OVX rats with osteopenia treated with organic gallium. Treatments were performed over an 8-week period. At sacrifice, the fifth lumbar vertebral body, one tibia, one femur, and the fourth lumbar vertebrae were removed, subjected to micro-CT for determination of trabecular bone structure, and then processed for histomorphometry to assess bone turnover. The femoral neck was used for mechanical compression testing. Treatment with organic gallium increased bone volume in OVX animals. Organic gallium-treated animals had significant increases in trabecular and cortical thickness and bone strength. The plasma total calcium and inorganic phosphate concentrations in OVX rats decreased and bone mineral content in the lumbar vertebrae and femur increased after treatment with organic gallium. These data provide an important proof of concept that organic gallium may represent a powerful approach to treating or reversing severe osteoporosis in humans.     

The effect of conjugated linoleic acid on calcium absorption and bone metabolism and composition in adult ovariectomised rats

The effect of conjugated linoleic acid (CLA) on postmenopausal bone metabolism has not been investigated. Therefore, forty-three adult ovariectomised (OVX) rats (8-9 rats per group) were fed either a control diet containing 40 g/kg soyabean oil (SBO diet) or the SBO diet with 0 (control OVX), 2.5, 5 or 10 g/kg of CLA (replacing soybean oil) for 9 weeks. A group of sham-operated (SH) rats were fed the SBO diet. OVX rats had significantly (P<0.05) lower femoral bone mineral density and macromineral concentration, and intestinal Ca absorption compared to SH rats. CLA supplementation had no effect on these parameters. Ex vivo PGE(2) biosynthesis by bone and urinary Pyr and Dpyr (markers of bone resorption) were significantly higher (P<0.001) in control OVX rats compared with SH rats, and were significantly (P<0.001) lowered by CLA supplementation with 5 and 10, but not 2.5 g/kg diet in OVX rats. In conclusion, CLA supplementation appeared to reduce the rate of bone resorption in adult OVX rats.     

Evaluation of the preventive effect of isoflavone extract on bone loss in ovariectomized rats

To examine a potential role for soybean phytoestrogens in postmenopausal bone loss, twenty-four 12-week-old Sprague-Dawley rats were divided randomly into 4 groups and given controlled diets for 16 weeks. The treatment groups were as followed: sham operated, ovariectomized (OVX) control, OVX + isoflavone extract (6.25 g/kg), and OVX + 17beta-estradiol (4 mg/kg). OVX treatments reduced femoral and fourth lumbar vertebral bone density and mineral content (p<0.01), decreased uterine weight (p<0.01), accelerated body weight increases (p<0.05), and increased the activities (p<0.01) of both serum alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP). Supplementation with isoflavone prevented the losses of bone density and mineral content caused by OVX (p<0.01). Although both isoflavone and 17beta-estradiol exhibited similar bone-sparing ability on the OVX-induced bone loss, the effect of isoflavone was not the same as that of 17beta-estradiol on the serum ALP and TRAP, body weight increase, and uterine weight change. We concluded that dietary supplementation with soybean isoflavone can prevent postmenopausal bone loss via a different mechanism of estrogen in OVX rats.     

Effects of Astragalus membranaceus with Supplemental Calcium on Bone Mineral Density and Bone Metabolism in Calcium-Deficient Ovariectomized Rats

It has been reported that Astragalus membranaceus, an Asian traditional herb, has an estrogenic effect in vitro. To examine the possible role of A. membranaceus extract with supplemental calcium (Ca) on bone status in calcium-deficient (LCa) ovariectomized (OVX) rats, a total of 48 female rats were divided into six groups: (1) normal control, (2) sham operation with LCa (sham-LCa), (3) OVX with LCa (OVX-LCa), (4) A. membranaceus supplementation with OVX-LCa (OVX-MLCa), (5) Ca supplementation with OVX (OVX-Ca), and (6) A. membranaceus and Ca supplementation with OVX (OVX-MCa). A. membranaceus ethanol extract (500 mg/kg BW) and/or Ca (800 mg/kg BW) were administered orally for 8 weeks along with a Ca-deficient diet. Results revealed that Ca supplementation with or without A. membranaceus extract significantly improved bone mineral density, biomechanical strength, and ash weight of the femur and tibia in OVX rats. High Ca with A. membranaceus combination supplementation significantly increased the ash weight of the femur and tibia and decreased urinary Ca excretion compared with supplementation of Ca alone. Uterine weight was not changed by A. membranaceus administration in OVX rats. These results suggest that A. membranaceus extract combined with supplemental Ca may be more protective against the Ca loss of bone than A. membranaceus or supplementation of Ca alone in calcium-insufficient postmenopausal women.     

High-impact exercise strengthens bone in osteopenic ovariectomized rats with the same outcome as Sham rats.

The effect of jump exercise on middle-aged osteopenic rats was investigated. Forty-two 9-mo-old female rats were either sham-operated (Sham) or ovariectomized (OVX). Three months after surgery, the rats were divided into the following groups: Sham sedentary, Sham exercised, OVX sedentary, and OVX exercised. Rats in the exercise groups jumped 10 times/day, 5 days/wk, for 8 wk, with a jumping height of 40 cm. Less than 1 min was required for the jump training. After the experiment, the right tibia and femur were dissected, and blood was obtained from each rat. OVX rats were observed to have increased body weights and decreased bone mass in their tibiae and femurs. Jump-exercised rats, on the other hand, had significantly increased tibial bone mass, strength, and cortical areas. The bone mass and strength of OVX exercised rats increased to approximately the same extent as Sham exercised rats, despite estrogen deficiency or osteopenia. Our data suggest that jump exercise has beneficial effects on lower limb bone mass, strength, bone mineral density, and morphometry in middle-aged osteopenic rats, as well as in Sham rats.     

葛根异黄酮对去卵巢大鼠骨质疏松症的影响

通过对3月龄Wister大鼠,手术切除双侧卵巢后7天,每天灌胃TIP40mg/kg和10mg/kg,并设去卵巢组(OVX)、假手术组(Sham)和尼尔雌醇阳性对照组(OVX-E2),在给药3个月时,测定大鼠股骨骨矿密度(BMD)、骨钙及血清钙水平等,研究葛根异黄酮(TIP)对由雌激素缺乏引起的骨质疏松症的防治作用。结果TIP40mg/kg的BMD比去卵巢组显著提高了18.1%;使胫骨和血清钙含量显著增加;使去卵巢大鼠的脾脏重量系数和胸腺重量系数明显恢复;并可明显控制大鼠的体重。葛根异黄酮可能具有雌激素样活性,并有改善骨质疏松症的生物学活性。     

Effect of shellfish calcium on the apparent absorption of calcium and bone metabolism in ovariectomized rats

Fossil shellfish powder (FS) and Ezo giant scallop shell powder (EG) were rendered soluble with lactate and citrate under decompression (FSEx and EGEx, respectively) and we examined the effects of lactate-citrate solubilization of FS and EG on mineral absorption, tissue mineral contents, serum biochemical indices and bone mineral density (BMD) in ovariectomized (OVX) rats. The apparent absorption ratios of minerals tended to be high in the rats fed with the solubilized mineral sources, those in the FSEx group being significantly higher than in the FS group. There was no significant difference in the tibia mineral content among the OVX groups. BMD at the distal femoral diaphysis was significantly increased by FSEx and EGEx feeding. It is suggested that solubilization with lactate and citrate under decompression increased the solubility and bioavailability of calcium from such natural sources of shellfish calcium as FS and EG.     

Effects of Multi-Deficiencies-Diet on Bone Parameters of Peripheral Bone in Ovariectomized Mature Rat

Many postmenopausal women have vitamin D and calcium deficiency. Therefore, vitamin D and calcium supplementation is recommended for all patients with osteopenia and osteoporosis. We used an experimental rat model to test the hypothesis that induction of osteoporosis is more efficiently achieved in peripheral bone through combining ovariectomy with a unique multi-deficiencies diet (vitamin D depletion and deficient calcium, vitamin K and phosphorus). 14-week-old Sprague-Dawley rats served as controls to examine the initial bone status. 11 rats were bilaterally ovariectomized (OVX) and fed with multi-deficiencies diet. Three months later the treated group and the Sham group (n = 8) were euthanized. Bone biomechanical competence of the diaphyseal bone was examined on both, tibia and femur. Image analysis was performed on tibia via µCT, and on femur via histological analysis. Lower torsional stiffness indicated inferior mechanical competence of the tibia in 3 month OVX+Diet. Proximal metaphyseal region of the tibia showed a diminished bone tissue portion to total tissue in the µCT despite the increased total area as evaluated in both µCT and histology. Cortical bone showed higher porosity and smaller cross sectional thickness of the tibial diaphysis in the OVX+Diet rats. A lower ALP positive area and elevated serum level of RANKL exhibited the unbalanced cellular interaction in bone remodeling in the OVX+Diet rat after 3 month of treatment. Interestingly, more adipose tissue area in bone marrow indicated an effect of bone loss similar to that observed in osteoporotic patients. Nonetheless, the presence of osteoid and elevated serum level of PTH, BGP and Opn suggest the development of osteomalacia rather than an osteoporosis. As the treatment and fracture management of both osteoporotic and osteomalacia patients are clinically overlapping, this study provides a preclinical animal model to be utilized in local supplementation of minerals, drugs and growth factors in future fracture healing studies.     

Manganese Supplementation Improves Mineral Density of the Spine and Femur and Serum Osteocalcin in Rats

The effect of manganese (Mn) supplementation on bone mineral density (BMD) and bone metabolism parameters was determined in ovariectomized Sprague-Dawley rats. Rats were divided into four groups (OVX, OVX+Mn, sham, sham+Mn) and fed with different intake levels of manganese (adequate 0.001% Mn, supplementation 0.01% Mn) for 12 weeks. BMD of the lumbar vertebrae, femur, and tibia were significantly lowered in ovariectomized rats compared to the sham group. In addition, BMD of the lumbar vertebrae was significantly increased by Mn supplementation in the sham groups. Serum C-telopeptide cross-links of type I collagen (CTx), bone resorption biomarker, alkaline phosphatase (ALP), and bone formation biomarkers were not significantly different among the four groups. However, serum osteocalcin, a more sensitive bone formation biomarker, was significantly increased by Mn supplementation. To summarize, Mn supplementation resulted in increased BMD and bone formation. Based on our findings, more research is needed to better understand the effects of manganese supplementation on bone formation and resorption.     

Effect of dietary calcium: Phosphorus ratio on bone mineralization and intestinal calcium absorption in ovariectomized rats

We investigated the effect of dietary calcium:phosphorus (Ca:P) ratio on bone mineralization and intestinal Ca absorption in ovariectomized (OVX) rat models of osteoporosis and sham-operated rats. Thirty 12-wk-old female Wistar rats were divided into three groups of OVX rats and three groups of sham rats. Thirty days after the adaptation period, OVX rats and sham rats were fed a diet formulated Ca:P, 1:0.5, 1:1 or 1:2 (each diet containing 0.5% Ca), respectively for 42 d. In both sham and OVX rats, serum osteocalcin, a marker of bone turnover, was increased by decreasing Ca:P ratio (1:2). In contrast, rats fed the Ca:P = 1:0.5 diet (dietary P restriction) suppressed the increased serum parathyroid hormone, osteocalcin and urinary deoxypyridinoline, and increased Ca absorption in both sham and OVX rats compared to the Ca:P = 1:1 and 1:2 diets. Especially, in OVX rats, the decreased bone mineral density of the fifth lumbar was also suppressed when rats were fed the Ca:P = 1:0.5 diet. These results indicated that the elevation of dietary Ca:P ratio may inhibit bone loss and increase intestinal Ca absorption in OVX rats.