维生素K对幼鼠骨代谢的影响

目的探讨不同剂量的维生素Ｋ对幼鼠骨代谢的影响。方法选用４０只雄性断乳大鼠，分为４组：１组饲料中维生素Ｋ水平为５０μｇ／ｋｇ，并添加１％磺胺药阻断肠道菌群合成维生素Ｋ，其余３组饲料维生素Ｋ水平分别为５０、３００、２５５０μｇ／ｋｇ。实验进行３个月，通过钙代谢实验、骨代谢生化指标及骨密度的改变，综合评价维生素Ｋ对幼鼠骨代谢的影响。结果不同剂量水平的维生素Ｋ对大鼠胃肠道钙吸收无显著影响；维生素Ｋ缺乏组动物尿钙、尿羟脯氨酸排出增高，提示维生素Ｋ缺乏导致骨分解代谢增强；血清骨钙素及股骨骨密度随膳食维生素Ｋ摄入水平增加而提高，高剂量组显著高于维生素Ｋ缺乏组，而凝血酶原时间各组间差异无显著性。结论目前根据凝血功能制定的大鼠饲料维生素Ｋ的供给量不能满足幼鼠骨生长发育要求，幼鼠骨发育对维生素Ｋ的需求很可能高于５０μｇ／ｋｇ饲料。     

对长期低钙摄入幼鼠的骨骼的研究——Ⅲ 低钙时幼鼠的骨钙素水平

本文研究低钙摄入、维生素D供给正常时幼鼠血中骨钙素水平,以了解低钙时成骨细胞活性。实验采用60只21～23日Wistar断乳幼鼠,随机分为四组:A组,正常钙与VitD摄X组;B组,中度低钙组;C组,重度低钙组;D组,VitD缺乏组。定期监测血25-(OH)D_3水平。于实验中期(3周),末期(6周)分别处死1/2幼鼠,取血与左股骨标本。测血骨钙素水平,以股骨钙与股骨长计算股骨含钙指数。实验建立低钙与低VitD动物模型。结果发现严重低钙幼鼠股骨生长显著落后,VitD缺乏幼鼠股骨生长与正常组相似。低钙与VitD缺乏幼鼠股骨含钙指数均明显低于正常组,低钙组更严重。低钙组幼鼠血骨钙素水平略高于正常组,VitD缺乏幼鼠血骨钙素有增高趋势;提示低钙时股骨增生的成骨细胞活性低下,VitD缺乏幼鼠骨生长受阻程度不如低钙组明显,推测VitD缺乏与低钙时对成骨细胞的作用机理不同。本文研究证实低钙对生长期骨骼的影响远远超过临床估计。     

对长期代钙摄入幼鼠的骨骼的研究：Ⅲ低钙时幼鼠的骨钙素水平

本文研究低钱摄入，维生素Ｄ供给正常时幼鼠血中骨钙素水平，以了解低钙时成骨细胞活性。实验采用６０只２１－２３日Ｗｉｓｔａｒ断乳幼鼠，随机分为四组：Ａ组，正常钙与ＶｉｔＤ摄Ｘ组；Ｂ组，中度低钙组；Ｃ组，重度低钙组；Ｄ组，ＶｉｔＤ缺乏组。定期监测血２５－（ＯＨ）Ｄ３水平。     

钙缺乏对大鼠骨骼发育的影响及其机制探讨

在建立钙缺乏动物模型的基础上 ,利用骨形态计量学方法观察缺钙对生长期大鼠骨骼发育的影响 ,并通过测定血清有关激素的变化探讨其机制。组织形态学显示缺钙大鼠骨形成量减少 ,矿化能力降低 ,空间结构破坏 ;同时钙缺乏大鼠骨矿物质含量和骨密度均显著降低 ,血清甲状旁腺激素水平明显增高 ,降钙素水平显著降低 ;骨组织羟脯氨酸含量降低。提示钙缺乏通过影响骨骼矿物质含量、激素分泌以及有机质形成 ,使骨形态结构发生异常改变 ,最终导致骨骼发育障碍     

佝偻病患儿成骨细胞分子标志物的研究

目的：通过对佝偻病患儿骨钙素（OC），骨碱性磷酸酶（BALP），I型前胶原羧基端前肽（PICP）和25－羟维生素D3[25-(OH)D3]的检测，观察其成骨细胞的功能状况，以便探讨合理的治疗原则。方法：选择40例维生素D缺乏性的佝偻病患儿为受试对象，年龄为6个月－1岁，男18例，女22例，取血后即注射维生素D3030万IU，4－5周后，复查者18例，同时检测了年龄，性别相匹配的20例健康婴儿作为正常对照，男7例，女13例。结果：（1）佝偻病患儿治疗前血清BALP，PICP与对照组相比显著升高，而OC，25－（OH）D3与对照组相比显著降低。（2）给予维生素D34－5周后，与治疗前相比，BALP和PICP值明显下降（P＜0．1）；而OC和25－（OH）D3则明显升高（P＜0．01）。（3）佝偻病患儿各指标之间的相关性；25－（OH）D3与OC呈正相关（P＜0．01）OC车BALP呈负相关（P＜0．01）；BALP与PICP呈正相关（P＜0．01）。结论：作为成骨细胞的分子标志物OC，BALP和PICP，可以反映佝偻病患儿的骨矿化程度。     

孕妇血清25羟维生素D与血清离子钙检测结果分析

目的通过测定3 645例丽水市区孕妇血清25羟维生素D(25-OH-D)和血清离子钙(i Ca2+)水平,分析目前本市孕妇维生素D和血清离子钙的状况,预防妊娠期妇女维生素D及离子钙的缺乏对胎儿骨骼生长发育的影响。方法于2014年2月-2015年9月采集受试者血清后,采用化学发光法测定25羟维生素D,离子选择电极法测定离子钙。结果 2组维生素D缺乏的比率妊娠组为54.2%,对照组为42.3%,但妊娠组25羟维生素D严重缺乏率为35.7%,而对照组25羟维生素D严重缺乏率为1.65%。结论在妊娠妇女中普遍存在的25羟维生素D不足,但离子钙下降较为缓和,应加强25羟维生素D和钙的补充。     

孕晚期妇女服用钙及维生素D初步观察

目的观察孕晚期妇女服用钙及维生素D对孕期妇女低钙和维生素D缺乏的效果.方法对24例孕28周后的晚期妊娠妇女,每日服用碳酸钙加维生素D1片.并与同期11例不服任何钙剂及维生素D3的晚期妊娠妇女(对照组)进行比较.结果(1)用药组产前血清钙(Ca)、磷(P)、骨钙素(BGP)及25羟基D3(25OHD3)明显高于用药前的孕28周(P＜0.001);而对照组产前与孕28周比较无明显变化.(2)给药组产前尿羟脯氨酸与肌酐比值(HOP/cr)、尿钙(Ca)与肌酐比值(Ca/cr)比孕28周明显减少.(3)尿中Ⅰ型胶原交联C末端肽与肌酐比值(crosslaps/cr)给药组,和对照组在产前明显高于孕28周(P＜0.001),但产后42天,给药组明显低于对照组(P＜0.001).(4)两组血清碱性磷酸酶(AKP)产前明显均高于孕28周时水平(P＜0.001),表明胎盘产生大量AKP.结论孕期服用碳酸钙加维生素D3有明显促进骨形成,抑制骨吸收的作用和提高血清钙、磷的作用.给药8～10周后,虽然25OHD3比治疗前有明显升高,但仍低于同年龄健康妇女的水平,提示对孕产妇应适当增加维生素D3的用量.     

钙和维生素D系统对骨骼和钙体内平衡的影响

基因打靶除去编码 1 ,2 5 -二羟维生素 D合成酶、2 5羟维生素 D羟化酶及 1 ,2 5 -二羟维生素核受体、维生素 D受体基因 ,可建立有用的人类疾病小鼠模型 ,维生素 D依赖性软骨病 型与 型 ,应用这种模型及双敲除突变体研究了钙和 1 ,2 5 -二羟 D/维生素 D受体系统对骨骼和钙体内平衡的影响。最佳饮食钙吸收要求 1 ,2 5 -二羟维生素 D/维生素 D受体的存在。骨骼矿化需要外周血清钙离子达到一定浓度 ,但不是直接需要 1 ,2 5 -二羟维生素 D/维生素 D受体系统的存在。甲状旁腺激素分泌也主要是通过外周血清钙调节 ,但是使变异增大的甲状旁腺和加宽的软骨生长板恢复正常 ,必需通过钙和维生素 D的结合才能进行 ,明显和维生素 D受体的存在与否无关。最佳的破骨细胞骨吸收和成骨细胞的骨形成都需要完整的 1 ,2 5 -二羟维生素 D/维生素 D受体系统的参与。结果表明 :在骨骼和体内钙平衡中 ,钙离子不能完全替代维生素 D,但这两者存在着不连续而又重叠的功能。     

维生素D与骨的生长和矿化

维生素D通过调节肠道和肾脏对钙磷的吸收和重吸收、骨钙的转移来调控矿物质的生理平衡，调节骨的矿化和生长。1，25(OH)2D3是活性最强的维生素D代谢产物，通过维生素D受体来发挥作用，体内还有一种细胞膜相关性快反应类固醇结合蛋白路径，通过基因和非基因两条路径维生素D调节和控制着骨的生长和矿化。     

维生素K与钙对去卵巢大鼠骨代谢的影响

切除雌鼠双侧卵巢造成快速骨丢失,复制女性绝经后骨质疏松症的动物模型。以饲料添加方式补充维生素Ｋ（９０ｍｇ／ｋｇ） 和钙（５ｇ／ｋｇ） 。实验期６ 个月,通过测定尿钙、尿羟脯氨酸、血清钙、碱性磷酸酶、骨钙素等生化指标观察单纯补充维生素Ｋ、钙及两者联合作用对骨代谢的影响。结果发现：补充Ｖｋ 可减少尿钙、尿羟脯氨酸排泄,降低血清碱性磷酸酶水平,提高血清骨钙素及其羧化水平,表明维生素Ｋ 能抑制骨分解代谢,促进骨形成代谢,并且与钙的联合作用效果优于单纯补充维生素Ｋ 或钙。本实验结果提示：绝经后妇女作为骨质疏松危险人群,应注意膳食维生素Ｋ 与钙的摄入。大剂量的维生素Ｋ 有可能被用于骨质疏松症的药物防治     

维生素D及钙营养缺乏对雏鸡骨骼发育影响

目的 建立ＶｉｔＤ缺乏、钙缺乏雏鸡动物模型,比较两种情况下骨生长情况。分析两种营养素对骨骼发育的影响。方法 建立动物模型。采用反相高效液相色谱法、离子电极测量技术、双维骨密度测定仪、原子吸收分光光度仪分别测血维生素Ｄ、离子钙、骨密度、骨钙含量等。结果 单纯钙缺乏和ＶｉｔＤ缺乏组雏鸡其骨密度、骨矿含量、骨含钙量、骨宽、骨长、骨重均低于正常组,以ＶｉｔＤ缺乏组降低尤为明显,且其生长板软骨明显增厚,软骨     

乳酸钙防治实验性骨质疏松的研究

对１２月龄雌性Ｗｉｓｔａｒ大鼠行双侧卵巢切除术一个月后，每天灌胃给予乳酸钙连续三个月。结果发现，与手术对照组相比，乳酸钙中剂量［２５０ｍｇ／（ｋｇ．ｄ）］能明显增强大鼠股骨骨密度（ｐ＜０．０５），低剂量［１２５ｍｇ／（ｋｇ．ｄ）］能明显降低大鼠血清碱性磷酸酶的活性（Ｐ＜０．０５），高［７５０ｍｇ／（ｋｇ．ｄ）］、中、低剂量均明显增加血清钙的含量（Ｐ＜０．０１），明显降低２４小时尿羟脯氨酸／肌酐比值（Ｐ＜０．０５），中、高剂量能明显增加２４小时尿钙／肌酐比值（Ｐ＜０．０５）、股骨灰分重及灰分与干重的百分比，而对股骨湿重、干重、体积及血清骨钙素的含量无明显影响。结果提示，乳酸钙具有抑制骨吸收作用，其防治骨质疏松作用机理主要与适当增高体内钙水平有关     

Interactions of vitamin D with sodium zeolite A in rats from low and adequate vitamin D colonies.

Weanling rats (21 days old) from either a low vitamin D colony or an adequate vitamin D colony fed either a vitamin D adequate or a vitamin D deprived AIN-76A purified diet were used as a model to investigate interactions of vitamin D status with dietary sodium zeolite A (100 mg/kg body wt/day). Rats with adequate or replete vitamin D status had greater overall body weight gain, dry tibia weights and femur densities and ash weights than rats fed a vitamin D deprived diet. Addition of sodium zeolite A to the diets did not have an effect on plasma calcium, body weight gain or on femur density, ash and percent ash. Dietary sodium zeolite A increased total tibia fat in rats fed the vitamin D adequate diet and decreased total tibia fat in rats fed the vitamin D deprived diet. This effect of sodium zeolite A appeared to be beneficial to bone status in the groups fed adequate vitamin D, since these treatment groups had higher, although not significant, dry tibia weights with and without fat.     

市售品补钙制剂的补钙效果观察

以大鼠为模型，研究市售数种钙剂的补钙效果。选用三周龄断乳Ｗｉｓ－ｔａｒ大鼠１０８只，雌雄各半，喂饲３周缺钙饲料后，按体重随机把大鼠分成９组，即以基础饲料为缺钙对照组，以碳酸钙为补钙正对照组，其它７组为市售商品钙制剂，包括：１．碳酸钙＋ＶＤ产品、２．中药补钙＋ＶＤ产品、３．骨粉产品、４．活性钙片、５．活性钙冲剂、６．乳酸钙冲剂、７．醋酸钙产品。按产品标识量加入３０００ｍｇ钙／ｋｇ，使饲料含钙量达到大鼠推荐量的８０％。补钙各组大鼠终体重和身长均非常显著高于对照组。补充商品钙制剂组的血浆、红细胞和肝脏中钙含量均显著高于缺钙对照组，补钙各组间无显著差异。多数钙制剂对雄性肾脏钙存留的影响不显著，只有活性钙片和中药补钙＋ＶＤ显著增加雄性大鼠肾脏钙存留；补钙对雌性大鼠肾脏钙存留的影响非常显著。补充商品钙剂均显著增加骨矿物质含量，醋酸钙冲剂和活性钙的效果似不如其它钙制剂。按效果价格比，目前碳酸钙仍是最好的钙源。     

Bioavailability of vitamin D2 from irradiated mushrooms: an in vivo study

Vitamin D2 from irradiated edible mushrooms might present a possible dietary source of this vitamin, subject to its bioavailability. Having previously optimized a method for the conversion of ergosterol in mushrooms to vitamin D2, this paper examines the vitamin D-enriched mushrooms (Lentinula edodes) for their bioavailability of the vitamin, using an animal model. Thirty male Wistar rats were fed for 1 week with a diet deficient in vitamin D. After this 1-week period, six rats were randomly selected and killed for analysis of initial bone mineral density, and serum level of 25-hydroxyvitamin D. A group of twelve rats of the test animals received 1 mug of vitamin D2 from irradiated mushrooms for a period of 4 weeks until being killed. The remaining twelve rats were fed un-irradiated mushrooms at the same level to act as controls. At the end of a 4-week period, the mean serum 25-hydroxyvitamin D level of the experimental group was 129.42 (sd 22.00) nmol/l whereas it was only 6.06 (sd 1.09) nmol/l in the control group. Femur bone mineral density of the experimental group of animals was significantly higher (P<0.01) than the control group. In addition, serum Ca concentrations among groups were shown to be significantly higher (P<0.01). It may be concluded from the results that vitamin D2 from UV-irradiated mushrooms is well absorbed and metabolized in this model animal system. Significant increase in femur bone mineralization (P<0.01) was shown in the presence of vitamin D2 from irradiated mushrooms compared with the controls.     

Dietary lactose improves endochondral growth and bone development and mineralization in rats fed a vitamin D-deficient diet

Lactose promotes the intestinal absorption of calcium independent of the vitamin D endocrine system. The purpose of this study was to determine the effect of lactose supplementation on endochondral bone growth, bone development and mineralization in weanling rats fed a vitamin D-deficient diet. Rat pups were weaned from vitamin D-deficient dams and fed a vitamin D-deficient diet containing sucrose as the primary carbohydrate source or a similar diet but containing 20% lactose. After 4 wk, body weights, serum calcium levels and endochondral bone elongation rates in the lactose-fed animals were higher than in rats fed the sucrose diet. In addition, bone weights, bone calcium content, percent bone ash of bone dry weight, percent metaphyseal osseous tissues and bone osteoid content in the lactose-fed rats were different from those in the rats fed the sucrose diet. In all cases the changes in osseous tissues that were observed in the animals fed the lactose-supplemented diet were toward normal values as observed in age-matched animals fed a vitamin D-replete diet. The improvements in bone growth and development due to lactose supplementation occurred independent of the vitamin D endocrine system and are likely the result of improved calcium absorption in the intestine.     

Effects of long-term dietary manganese and copper deficiency on rat skeleton

Experiments were designed to produce biochemical changes in both serum and bone in rats by long-term dietary deficiencies of manganese (Mn) and copper (Cu). Weanling rats were fed one of three diets: 1) normal Mn and Cu (N), 2) low Mn and Cu (L) and 3) depleted Mn and normal Cu (D). After 12 mo, serum Ca and P were significantly greater in the D rats than the N rats (134, 50 mg/L and 103, 39 mg/L, respectively). Serum and femur Mn levels were lower in D rats than in normal rats. Serum and femur Cu levels were lower in L rats than N rats. Femur Ca concentrations were significantly lower in D rats than in N rats (180 and 272 mg/g, respectively). Radiographic differences could be detected in some rats fed the L and D diets. In the two deficient groups, increased serum Ca was negatively correlated with bone Ca (r = -0.69; P less than 0.01). This biochemical association may represent alterations in regulatory control of Ca at the level of the bone (decreased mineralization) combined with an increase in bone resorption. The effect of long-term dietary deficiencies in Mn and Cu should be considered in human bone metabolism.     

Sodium and calcium intakes and bone mass in rats revisited

OBJECTIVE: High sodium intake accompanied by insufficient dietary calcium may have detrimental effects on bone mass. Our study evaluated the effects of increased sodium and decreased calcium intakes on bone mineral density (BMD) and bone mineral content (BMC) in rats. METHODS: Four-month-old female Wistar rats were given deionized water or 1.8% solution of sodium chloride in deionized water and fed normal (1.2%) or marginal (0.33%) calcium in the diet for 2 mo. At the end of the experiment, BMD and BMC of the whole body and urinary sodium and calcium excretion were evaluated. All rats were killed and right femurs were removed to assess dry and ash weights. Two-way analysis of variance was used to evaluate effect of salt intake and effect of dietary calcium on these parameters. RESULTS: Salt-loaded animals had greater water consumption during the entire 2-mo period and significantly lower body weight from week 5 of the experiment. High salt intake increased urine volume and urinary excretion of sodium and calcium. Urinary calcium was about five times higher in salt-loaded animals than in rats on deionized water irrespective of dietary calcium content. Calcium in diet itself had no significant effect on these parameters. High salt intake slightly, but not significantly, decreased BMD, BMC, and femur weights. Lower calcium in diet significantly decreased BMD, and its effect on femur ash weight almost reached a level of significance. CONCLUSION: We confirmed the benefit of adequate calcium intake to BMD. Under our experimental condition, high salt intake in rats for 2 mo had no statistically significant effect on femur weights, BMD, or BMC even with marginal calcium in the diet.     

低聚半乳糖与聚葡萄糖联用对生长期大鼠钙代谢和骨量的影响

目的 探究低聚半乳糖(galacto - oligosaccharides,GOS)与聚葡萄糖（polydextroses,PD）联用对生长期大鼠骨代谢和骨钙含量的影响。方法 60只刚断乳SD大鼠随机分为低钙组（饲料钙0.15%）、正常组（饲料钙0.5%）、强化组（饲料钙0.375% + 维生素D强化）、低比组（强化组饲料 + PD 2.5% + GOS 2.5%）和高比组（强化组饲料 + PD 4% + GOS 1%）5个组,分别饲喂含钙、维生素D3和益生元含量不同的饲料。观察大鼠一般情况,记录体重,于实验第83 d进行3 d的钙代谢实验,原子吸收法检测饲料、粪便和尿液中的钙含量,计算钙表观吸收率和储备率;喂饲93 d后处死,取心肝脾肾称重计算脏器系数,取血清测定血清钙、磷水平,取股骨测股骨干重,并采用原子吸收法测量股骨钙含量。结果 实验结束时,正常组、低比组和高比组体重均显著高于低钙组;各组的钙表观吸收率和钙储留率显著低于低钙组;与低钙组比较,各组的血清钙和骨钙含量都显著增加;低比组和高比组的股骨重和骨钙含量显著高于强化组,与正常组无显著差异。结论 充足的钙摄入对生长期大鼠的钙代谢及骨骼生长具有重要意义;聚葡萄糖和低聚半乳糖联用可增加生长期大鼠的骨钙含量。