Bone tissue response to four-month antiorthostatic bedrest: A bone histomorphometric study

Summary A histomorphometric analysis were made on iliac crest biopsies from eight healthy male volunteers submitted to a 4-month antiorthostatic bedrest. Bone mass and bone cell parameters, reflecting resorption and formation activities, were measured before and after the bedrest period. Trabecular bone volume and mean cortical thickness were not modified despite a decreased number of trabeculae and nonsignificant increase of the trabecular thickness; total and active resorption surfaces and the number of osteollast per mm² of trabecular surfaces do not vary significantly. Osteoid thickness does not vary but we found a reduced osteoid surface and a nonsignificant decreased osteoid volume. Our results suggest that bone architecture may be more affected by the reduction of mechanical forces than the bone mass. These modifications were supposed to be the result of an accelerated bone turnover in the early stage of immobilization. In this study, we failed to find disuse osteoporosis; however, we must point out that the new organization of the trabecutae could affect the bone mechanical properties.     

游泳运动对小鼠骨密度值和6种骨元素含量的影响

目的 观察游泳运动对小鼠骨密度值和6种骨元素含量的影响.方法 10月龄健康雌性ICR小鼠随机分为基础对照组(C1)、安静对照组(C2)、每日运动组(S1)和隔日运动组(S2).所有动物适应性饲养2周后,C1组小鼠处死作为基础对照,C2组安静饲养10周,S1组每周无负重自由游泳5天,S2组每周隔日无负重自由游泳3天,游泳时间均为每天1小时.持续运动10周后,对小鼠左侧胫骨、腰椎进行取材,进行骨密度的测试,ICP法对小鼠胫骨钙Ca、镁Mg、铜Cu、锰Mn、锌Zn、硼B等6种元素含量进行测试.结果 (1)运动对小鼠胫骨密度和腰椎骨密度值影响不大,但可降低灰重/干重比值(P＜0.01),提高骨有机质密度(P＜0.01).(2)除了Mg元素外,运动能使Zn、Ca、Cu、Mn、B等元素含量增加,其中Ca和B元素的含量,S2组显著高于S1组(P＜0.05).(3)相关分析显示,胫骨有机质密度与Zn元素含量呈正相关,与Mg元素含量呈负相关;腰椎骨密度与Mn、B元素含量呈显著正相关(P＜0.05).Ca与Mg、Mn、Cu、B等元素具有正相关,Cu、B、Mn三者之间呈显著正相关(P＜0.05).结论 小鼠骨密度和骨元素含量随增龄发生改变,无机成分增加,有机成分减少,提示骨朝脆性增加的方向发展.游泳运动对骨密度值影响不大,但可以通过骨元素的变化影响骨成分.     

Effects of neonatal estrogenization on rat bone development: A histomorphometric study

Summary The effects of a single dose of 500 μg of estradiol benzoate, administered on the first day of life, on rat bone development have been histomorphometrically studied at 15 days of age. Estrogenized animals presented decreased total tibial length (16.55±0.50 vs. 17.84±0.73 mm,P<0.05) and increased thickness of the cartilage growth plate (528.92±13.30 vs. 382.77±37.85 μm,P<0.01). This increase was mostly due to the presence of a wider (P<0.01) layer of hypertrophic cartilage in the estrogenized rats than in control ones. It might be related to the decreased number of chondroclasts (0.20±0.01 vs. 0.36±0.06 mm⁻¹,P<0.05) found in the resorption zone. Two metaphyseal zones have been considered. In the upper metaphyseal zone there was an increase in the surface density of the cartilaginous trabeculae (49.20±1.80 vs. 40.72±1.95 mm²/mm³,P<0.05), without changes in the volume density. It was related to the presence of thinner and more irregular trabeculae in the estrogenized animals. In the lower metaphyseal zone both the volume (0.19±0.01 vs. 0.14±0.01 mm³/mm³,P<0.01) and surface (34.83±3.01 vs. 26.52±2.46 mm²/mm³,P<0.05) densities of the osseous trabecular tissue were increased in estrogenized rats. No significant differences were found either in the number of osteocytes per area unit of osseous tissue or in the number of osteoclasts per unit length of trabecular osseous tissue.     

Dynamic histomorphometric evaluation of human fetal bone formation

We have evaluated dynamic and static parameters of bone formation in femoral metaphyses collected from two human fetuses at 19 weeks of gestation. Tetracycline was administered to the mother at set intervals (2-5-2 day schedule) before interruption of pregnancy. Labels were distinct and sharply linear, suggesting a well organized calcification front at this early stage of mineralization. Mineral apposition rate (MAR) was fastest (4.1 ± 0.3 μm/d) in the periosteal (Ps) envelope, and about half that value in the endosteal envelopes (endocortical: 2.5 ± 0.1, cancellous 2.1 ± 0.1 μm/d). Because cellular activities may vary throughout the metaphyseal area, sections were arbitrarily separated in 0.75 mm layers starting from the growth plate. Three measured parameters decreased rapidly with increasing distance from the physis: Ps MAR: 4.9 to 2.3 μm/d, trabecular osteoid thickness: 5.9 to 1.2 μm, and cartilage volume (CgV/TV): 5.4% to 1.2%. Others did not vary significantly along the metaphysis. Comparison of several static parameters with those measured in five autopsy specimens from full-term infants showed that bone and cartilage volume, and trabecular thickness increased while osteoid thickness and parameters of resorption decreased in the second half of the gestation period. The study indicates that fetal bone matrix mineralization is already highly organized at mid-gestation, and validates the use of histomorphometry to assess bone maturation during early skeletal development.     

染料木黄酮对去势大鼠骨组织形态计量学参数的影响

目的　研究染料木黄酮对去势大鼠股骨远端形态计量学参数的影响 ,为染料木黄酮防治骨质疏松提供理论依据。方法　雌性Wistar大鼠 4 7只 ,按体重随机分为 6组 :假手术组、去势对照组、去势 雌激素组 (2 0 μg/kg体重 )、去势 染料木黄酮组 (染料木黄桐剂量分别为 2 5、5 0、10 0mg/kg体重 )。饲养 3个月后处死 ,测定股骨形态计量学参数。结果　去势组与假手术组比较 ,骨小梁体积、平均骨小梁板密度和厚度减少 ,平均骨小梁板间隙和类骨质宽度增加 ,矿化延迟时间和类骨质成熟时间延长 ,且差异均具有显著性 (P <0. 0 5 )。染料木黄酮各组与去势组比较 ,骨小梁体积和平均骨小梁板厚度增加 ,平均骨小梁板间隙变窄 ,矿化延迟时间和类骨质成熟时间缩短 ,且差异均有显著性 (P <0 . 0 5 )。结论　染料木黄酮有促进骨形成 ,减少切除卵巢后骨量丢失的作用。     

骨形态计量学对增龄及去睾丸大鼠骨代谢的实验研究

目的 探讨３月半龄雄性大鼠增龄及去睾丸后骨量的变化,比较两之间骨代谢的变化。方法 ２０只３月半龄ＳＤ雄性大鼠,随机分成基础对照组、年龄对照组和去睾丸组,同等条件下饲养９０天。实验结束,取胫骨近端行不脱钙骨制片进行骨组织形态计量学分析。结果 年龄对照组（６月半龄）与基础对照组（３月半龄）相比,骨组织静态参数骨小梁面积百分率有下降趋势,骨的显微结构明显变差,动态参数如荧光标记周长百分率、骨形成率和单     

Bone mineral density and bone histomorphometric assessments of postpregnancy osteoporosis: A report of five patients

Reports of five young women who developed vertebral fractures associated with pregnancy and lactation are presented (Fig. 1). Ages ranged from 24 to 37 (mean 30) years. All five patients have osteoporosis with two to nine vertebral fractures at presentation postpartum. Bone mineral density (BMD) was measured by single-photon absorptiometry, quantitative computer tomography, and dual-energy X-ray absorptiometry. BMD of the trabecular bone was less than normal values and it remained apparently low even several years after pregnancy. Histological findings of bone biopsy identified the bone loss with increasing bone resorption. Our present findings suggest that postpregnancy osteoporosis affects mainly the trabecular bone site, and the patients might have low peak bone mass and poor reversibility probably due to a low rate of remodeling.     

双侧卵巢切除大鼠不同时间段骨形态计量学参数的观察

目的观察去卵巢大鼠骨质疏松模型复制情况并动态观察去卵巢后不同时间段骨丢失情况，为抗骨质疏松药物研究提供对照依据。方法4．5月龄SD雌性大鼠，按体重随机分组，大鼠摘除双侧卵巢；在实验的第0d（4．5月龄）、4w（5．5月龄）、12w（7、5月龄）、18w（9．5月龄）杀死大鼠取材；采用体内双荧光标记法，胫骨上段硬组织包埋切片及松质骨形态计量学分析处理，观察去卵巢后不同时间段骨丢失情况。结果大鼠去卵巢4w后骨量显著降低，骨结构变差，骨形成有增加，骨吸收增加，骨吸收大于骨形成，骨转换增加。去卵巢12w后，大鼠骨量进一步降低，骨小梁宽度先变窄（4w）后变宽（8、12、18w），骨形成和骨吸收均增加，去卵巢后大鼠在前一个月内（4w）骨量（Tb．Ar％）降低64．18％，差异有显著性（P〈0．05）。结论大鼠去卵巢4w后骨量降低，骨结构变差，骨形成和骨吸收增加，骨转换增加，去卵巢12w到18w骨量持续丢失，但较缓和，提示去卵巢后骨丢失在前4。最快更明显。因此，用于药物研究可选择去卵巢后4w时间进行。     

Electromagnetic stimulation of bone repair: a histomorphometric study

The effect of pulsing electromagnetic fields (PEMFs) on bone repair was studied in principal metacarpal bones of eight adult male horses: Six horses were treated with PEMFs, and two horses were untreated. In treated horses, Helmholtz coils were applied during a 60-day period to the left metacarpal bones, bored with eight holes of equal diameter and depth, from the middiaphysis toward the distal metaphysis. Eight equal holes bored in the right metacarpal, surrounded by unactivated Helmholtz coils, were taken as controls. The two untreated horses were taken as additional control. The results of computer-assisted histomorphometric analysis indicate that (a) in diaphyseal levels, the amount of bone formed during 60 days is significantly greater (p less than 0.01) in PEMF-treated holes than in contralateral ones and those in control horses; (b) in metaphyseal levels, PEMF-treated holes are sometimes more closed, sometimes less, as compared with contralateral holes and those in control horses; in any case the statistical analysis indicates that the symmetry in the rate of hole repair, found between the two antimeres of control horses, is not appreciable at metaphyseal levels also; (c) there was no statistically significant difference between untreated holes in PEMF-treated horses and holes in control horses, neither at diaphyseal nor at metaphyseal levels. These preliminary findings indicate that PEMFs at low frequency influence the process of bone repair on both diaphysis and metaphysis, and seem to improve the process of bone repair in skeletal regions normally having a lower osteogenetic activity, i.e., in diaphyses as against metaphyses.     

Difference in label length between demethylchlortetracycline and oxytetracycline: Implications for the interpretation of bone histomorphometric data

Summary We measured the individual lengths of fluorescent labels on the three subdivisions of the endosteal envelope in iliac bone biopsy specimens produced by the administration of both oxytetracycline and demethylchlortetracycline. Fifty-one healthy subjects and 53 patients with postmenopausal osteoporosis were labeled in the stated order, and 8 osteopenic patients were labeled in the reverse order. Whatever the order of administration, the demethylchlortetracycline label was longer than the oxytetracycline label. We conclude: (1) the difference in label lengths reflects a difference between the two compounds in some intrinsic property, whether physical, chemical, or pharmacokinetic. (2) If the calculation of extent of mineralizing surface is based on the mean length of the two labels, a suitable correction should be applied to the shorter label; alternatively, the length of the longer label alone should be used. (3) Unlabeled osteoid not due to label escape probably results from slow terminal mineralization after cessation of matrix synthesis during which too few tetracycline molecules are incorporated to exceed the threshold for visible fluorescence, rather than from the temporary interruption of mineralization followed by its resumption.     

Locally administrated single-dose teriparatide affects critical-size rabbit calvarial defects: A histological,histomorphometric and micro-CT study

ObjectiveThe aim of this study was to evaluate the effect of teriparatide (PTH 1-34, rhPTH) on a rabbit defect model with local xenogen grafts histomorphometrically and radiologically.MethodsFor this purpose, two 10 mm diameter critical-size defects were created in the calvaria of 16 rabbits. In the control group, the defect area was filled with a xenogen graft, while in the teriparatide group (PTH 1-34), a xenogen graft combination with 20 mcg teriparatide was used. For both 4 – week and 8 – week study groups, new bone, residual graft, and soft tissue areas were evaluated as well as bone volume histomorphometrically and radiologically.ResultsHistomorphometrically, there was a significant difference in new bone area values at the 8th week (p < 0.05), but there was no significant difference between the 4 – week values (p > 0.05). There was no statistically significant difference between the groups at both 4 and 8 weeks (p > 0.05). In the radiologically measured total bone volume values, PTH1-34 group values were found to be significantly higher for both 4 – and 8 – weeks values compared to the control groups (p < 0.05).ConclusionIn this study, rhPTH, which is used locally in defect areas to be repaired with bone grafts, increases both new bone volume and total bone volume.     

Effect of recombinant human granulocyte colony-stimulating factor (rh G-CSF) on rat bone: Inhibition of bone formation at the endosteal surface of vertebra and tibia

The effect of recombinant human granulocyte colony-stimulating factor (rh G-CSF) on bone was evaluated by histomorphometry using Sprague-Dawley rats. rh G-CSF was injected at doses of 0, 50, 150, and 450 μg/kg for 6 weeks.In vivo double fluorochrome labeling was performed before sacrifice. No significant change in body weight was observed. Bone mineral density (BMD) of lumbar vertebrae and femora was significantly decreased in G-CSF-treated groups. In the lumbar vertebra, osteoid surface, osteoid thickness, trabecular thickness, and labeled surface in G-CSF-treated groups were also significantly lower. In addition, osteoclast number and osteoclast surface were significantly higher in the G-CSF-treated groups. The endocortical surface at the mid-tibia showed lower labeled surface and mineral apposition rate in G-CSF-treated groups, without significant changes at the periosteal surface. Furthermore, numerous granulocytes fully occupied the bone marrow area. We conclude that proliferating granulocytes in the bone marrow may inhibit bone-forming cells from contacting the bone surface, resulting in reduction of bone formation;and increased osteoclastic bone resorption induced by G-CSF treatment contributed to the reduction of BMD.     

老年与青年股骨头内松质骨组织形态计量学比较研究

目的 研究老年部骨折患股骨头松质骨结构。方法 取股骨示本４９只,分成老年组２６例及青年组２３例。在股骨头致密区（负重区）和疏松区（非负重区）各截取软骨下３ｍｍ处７ｍｍ×５ｍｍ×５ｍｍ松质骨各一块作骨组织形态计量测定。结果 老年组致密区和稀疏区骨组织形态参数松质骨体积（ＴＢＶ）、平均骨小梁密度（ＭＴＰＤ）、平均骨小梁厚度（ＭＴＰＴ）、骨小梁间连接点数（Ｔｂ、ｎ）均明显低于青年组（Ｐ〈０．０５～０．     

Effect of calcitonin on bone histomorphometry and bone metabolism in rheumatoid arthritis

Summary Twenty-four women (mean age±SD 49±13 years) with classical or definite rheumatoid arthritis (disease duration 15±8 years) were treated with synthetic salmon calcitonin (SCT) nasal spray 200 IU three times a week for 3 months. Bone biopsies from the iliac crest were taken before and after SCT treatment. Histomorphometrical quantification of undecalcified bone sections was made using the manual point-counting method. SCT decreased the resorption surface of trabecular bone (ES/BS) significantly (P< 0.001). There was also a significant increase (P< 0.05) in trabecular bone volume (BV/TV) after 3 months of treatment, whereas no statistically significant changes were found in osteoid parameters. There were no significant changes in biochemical analyses of bone metabolism. We conclude that SCT might be useful in the prevention of bone loss in RA.     

Trabecular bone cell proliferationex vivo increases with donor age in the rat: It is correlated with the extent of bone loss and not with histomorphometric indices of bone formation

Morphometric parameters of bone formation are markedly depressed in senescent, 21-month old rats and even in middle-aged, 12-month-old animals when compared with mature, 4-month old adults. However, osteoblast-like cells obtained from the metaphyseal trabeculae of the distal femur of 21-month-old female and male rats proliferate more rapidly in primary and secondary cultures than cells from 4-month-old donors. In females the increase in proliferation is significant for donor ages from 4 to 12 months and from 12 to 21 months.Ex vivo cell proliferation is inversely correlated with trabecular bone volume and bone surface in females and with bone surface in males. The relationships are being maintained in females (not tested in males) when cells are grown in serum-free medium. We interpret age and bone loss-dependent stimulated cell proliferation as thein vitro response to anin vivo signal to proliferate resulting from higher strains on less trabeculae. The absence of responsein vivo could result from the local deficiency of factors brought back to the cells by the serum-enriched culture medium, or from proliferation inhibitors developing with age.     

补骨胶囊对去睾丸大鼠骨代谢影响的定量研究

目的观察补骨胶囊防治大鼠去睾丸致骨质疏松的作用及其机理的探讨。方法２１只３月半龄ＳＤ雄性大鼠,随机分成年龄对照组、去睾丸组和补骨胶囊用药组（含淫羊藿,黄芪,白术）按５ｍｌ．ｋｇ＾－１。ｄ＾－１ｉｇ,持续９０天。实验结束,取胫骨近心端行不脱钙骨制片进行骨组织形态计量学分析。结果去睾丸９０天大鼠的骨量与年龄对照组比明显下降（骨小梁面积百分率％Ｔｂ．Ａｒ－５０％）;补骨胶囊用药组骨量高于去睾丸组（％Ｔｂ     

The bone histomorphometric study of the bone growth as revealed by scanning electron microscopy

The present study was made with a view to examining the availability of the SEM observation method for bone histomorphometry. On Wistar strain newborn rats, 3 segments for measurement, i.e. temporal segment, middle segment and sagittal segment were prepared in the central part of the parietal bone endocranial aspects, and the bone surfaces were observed by SEM up to the fifteenth day at intervals of five days from after birth to measure areal volumes of the resorbing bone surface, forming bone surface and intermediate surface and change in the number of osteocyte lacunae in the forming bone surface, using Zeiss IBAS 2000. The results revealed that the resorption process preceded the forming process for the temporal segment from about the tenth day, the forming process preceded the resorbing process from the fifth day for the middle segment and the forming process preceded from the beginning for the sagittal segment. These findings directly reflect an aspect of the growing process of parietal bone, making it possible to regard this SEM observation method as one of the effective approaches to the bone histomorphometry.     

Effects of orally administered prostaglandin E-2 on cortical bone turnover in adult dogs: A histomorphometric study

The effects of Prostaglandin E-2 (PGE-2) on cortical bone turnover in ribs and femurs of 32 intact adult dogs were evaluated following 3 months treatment. Static and dynamic histomorphometric skeletal changes were characterized using terminal in vivo tetracycline double labeling. PGE-2 caused a dose dependent increase in the formation of subperiosteal fibrous-lamellar new bone in femurs, and an increase in bone remodeling within the (original) cortical compacta of both femurs and ribs. Increased cortical remodeling resulted in a new steady state, but only in ribs. Increased Haversian remodeling in ribs and femurs was characterized by increases in the activation frequency, the number of bone resorbing and forming foci, the percent of osteons with single labels, and the radial closure and bone formation rates, with no effect on appositional rate. While the mean ratios of the number of resorption to formation foci (R/F) were unremarkable in femurs of treated versus control males, the R/F ratios in treated females were approximately 50% lower than matched controls. In treated males, both femoral osteon resorption and formation times were 50% shorter than matched controls. In treated females, femoral osteon résorption time was 2–4-fold shorter than the decrease in osteon formation time. Calcium and phosphorus levels were normal in all treated dogs. Serum alkaline phosphatase levels were increased approximately twofold in high dose (10.0 mg/kg) dogs and correlated well with the histologie findings of increased skeletal turnover and bone formation.     

骨形态计量学观察丹参骨宝对环磷酰胺大鼠胫骨上段的影响

目的用环磷酰胺造成大鼠的骨丢失，观察丹参骨宝的影响。方法用4．5mg·kg^-1·d^-1的环磷酰胺灌胃给大鼠，连续15d，造成大鼠骨丢失；用丹参骨宝进行预防给药。实验结束后，取大鼠左侧胫骨上段进行不脱钙包埋切片作骨组织形态计量学测量。同时观察大鼠胸腺、脾脏的重量指数，以及外周血白细胞数量。结果环磷酰胺可使大鼠外周血白细胞数量和脾脏指数明显下降，本实验剂量的丹参骨宝不能有效对抗这种免疫抑制。环磷酰胺通过明显抑制骨形成而导致骨量减少，骨显微结构退化等典型骨质疏松特征的出现。丹参骨宝能通过增加骨的沉积矿化率，促进成骨活性而增加环磷酰胺大鼠的骨量，改善骨微观结构。结论丹参骨宝可有效预防环磷酰胺所引起的大鼠骨丢失，其预防机制与促进骨的矿化沉积率，增加骨形成活性有关。     

Effect of hypophysectomy on longitudinal bone growth in the rat

The effect of hypophysectomy on the growth in length from the proximal growth plate of the tibia in female Sprague-Dawley rats was studied with the tetracycline method. The body weight was registered. The completeness of the hypophysectomy was determined microscopically on serial sections of the sella turcica. Hypophysectomy was found to have a retarding effect on longitudinal bone growth. In animals operated at 40 days of age the growth does not cease. The longitudinal growth decreases and reaches a low basal level about 10 days postoperatively. A single dose of 45 mg/kg cortisone acetate given at hypophysectomy has a growth retarding effect postoperatively. When hypophysectomy was performed at 30, 40, 50, or 60 days of age, young animals have a higher basal growth rate than older animals. The width of the fluorescent band, corresponding to a postoperative injection of oxytetracycline, is correlated to the growth rate and can be used as an index of the growth rate. The postoperative accumulated growth and the width of the fluorescent band indicate the functional efficacy of the hypophysectomy, and make it possible to separate animals with complete and incomplete hypophysectomy. Knowledge about the basal growth is important for the evaluation of the growth stimulating effect of different hormones.