Effect of ofloxacin on the uptake of [3H]thymidine by articular cartilage cells in the rat

Ofloxacin (900 mg/kg) was orally administered to Sprague-Dawley rats aged 4 weeks. A single dosage induced chondrocyte degeneration in the middle zone of the articular cartilage 5 h later and cavity formation 12 and 24 h later. The number of cells labeled with [3H]thymidine was decreased in histologically normal and abnormal cartilage at 5 h. Incorporation rate of [3H]thymidine into the articular cartilage was gradually decreased until 12 h later, but increased above the control level at 24 h. Another experiment showed that labeled cells were retained for a longer period than in control rats in the middle zone at the predilection site of osteochondrosis.     

Dose related effects of dexamethasone treatment on the ultrastructure of articular cartilage in rats

Corticosteroid administration is known to cause degenerative changes in articular cartilage interfering with the cell metabolism of chondrocytes. The present study analyzes the ultrastructural changes in chondrocytes after systemic dexamethasone acetate treatment in relation to dosage, using a standardized morphometrical method. Five male Wistar rats of 300 g body weight in each experimental group were subjected to 3, 4 and 5 mg dexamethasone acetate by intramuscular injections of 1 mg per week. 1000 electron micrographs of single chondrocytes in the middle zone of hyaline cartilage from the knee joints were evaluated with standardized morphometry and nonparametric statistics. With increasing dexamethasone dosage the amount of rough endoplasmic reticulum and Golgi apparatus decreased. Considerably increased glycogen granula and clusters indicated a severe change in glycolytic pathways. Lysosomes duplicated in number. Degenerative changes were also manifested in lipid droplets and myeloid bodies, which, like the amount of microfilaments, exhibited a clear dosage-dependent increase under dexamethasone treatment. The ratio of dead versus living chondrocytes increased in relation to dosage up to 25% cell mortality.     

Morphological Investigation of Osteochondrosis Induced by Ofloxacin in Rats

Morphological Investigation of Osteochondrosis Induced by Ofloxacinin Rats. Kato, M., and Onodera, T. (1988). Fundam. Appl. Toxicol.11, 120–131. Oral doses of 300 or 900 mg/ kg/day of ofloxacin,a quinolone antibacterial agent, for 8 weeks induced a highincidence osteo-chondrotic lesions in rats. The predilectionsite of the lesions was the caudal area of the medial femoralcondyle. Early changes included thickening of the middle zoneof the articular cartilage with a markedly thinned deep zone.As the course of administration progressed, the columns of chondrocytesin the thickened middle zone became more and more numerous,many degenerated cells were seen, and the staining intensityof the matrix of the cartilage with safranin-O decreased slightly.After the completion of dosing, the articular cartilage wasmarkedly thickened and was made up mainly of middle zone cartilage.In advanced cases, a cleft was formed along the tidemark whichoccasionally extended to the articular surface. This resultedin erosion of the articular cartilage. Beneath the cleft therewere focal necrosis of the subchondral bone and fibrotic lesionsin the marrow space. Nalidixic acid also produced similar lesionsin rats. The two drugs induced osteochondrosis in rats whentreatment began at 4 weeks of age, but not at 8 weeks of age.This lesion was different in developmental process from thespontaneous osteochondrosis of rats, which is characterizedby retention of the inherently thick deepzone.     

Effects of magnesium deficiency on joint cartilage in immature Beagle dogs: immunohistochemistry,electron microscopy,and mineral concentrations

Quinolone-induced chondrotoxicity is possibly associated with the magnesium-chelating properties of quinolones. This toxic effect seems to be restricted to a rather short time period during postnatal development as shown in rats and dogs. We studied developmental changes of the integrin pattern on canine chondrocytes (e.g. the alpha(v)beta(3)- or alpha(5)beta(1)-integrin), because integrin function depends on divalent cations, as well as the matrix composition (e.g., collagen type II, fibronectin), in 11-, 18-, and 55-week-old Beagles (n=8) by immunohistochemistry. We also analyzed the magnesium and calcium content by atomic absorption spectroscopy in cartilage and bone and studied the effects of a magnesium-deficient diet on joint cartilage in four immature Beagles (18 weeks old at necropsy). The dogs were fed the magnesium-deficient diet for 40 to 46 days. All dogs exhibited gait alterations ('limping') after 4 weeks on the magnesium-deficient diet. Male, magnesium-deficient dogs exhibited pronounced weakness in their front legs; in one of these dogs the front legs were hyperextended to a 90 degrees angle. We observed no significant differences in the integrin pattern in samples from dogs at different developmental stages or in magnesium-deficient dogs in comparison to age-matched controls. Localization of fibronectin in the joint cartilage was found to vary with the age of the dogs as well as with the site of collection. In the middle zone of immature joint cartilage, corresponding to the predilective site of quinolone-induced cartilage lesions, we observed a slight increase in staining with the fibronectin antibody in some samples from magnesium-deficient dogs. Electron microscopy revealed alterations in chondrocytes from the magnesium-deficient dogs (e.g., swollen mitochondria and enlarged endoplasmic reticulum) which are also seen after treatment with quinolones. In summary, we found no significant differences of the integrin pattern on chondrocytes from joint cartilage of dogs at various developmental stages. However, magnesium deficiency in immature dogs induced similar clinical symptoms as quinolone treatment as well as distinct alterations in chondrocytic fibronectin staining and their ultrastructure. This corroborates our findings in rats where magnesium chelation is an important event in quinolone-induced chondrotoxicity.     

清络通痹颗粒对佐剂性关节炎大鼠骨质破坏影响的研究

目的:研究清络通痹颗粒(QLT)对佐剂性关节炎大鼠骨质破坏的影响。方法:制备佐剂性关节炎(AIA)大鼠模型。自模型制备第7天开始给予不同剂量的QLT,持续49d。各组大鼠进行关节摄片,观察骨质破坏情况。取各组大鼠滑膜细胞培养上清液,分别加入体外培养的软骨细胞中,观察软骨细胞增殖反应、软骨细胞上清液中一氧化氮(NO)含量及诱导型一氧化氮合酶(iNOS)表达的变化情况。结果:QLT3个剂量组可不同程度地改善AIA大鼠后肢关节的骨密度降低、关节腔间隙增宽、关节结构破坏等表现;QLT7.2、14.4g.kg-1给药的AIA大鼠滑膜细胞培养上清液可增强软骨细胞的增殖能力,降低其iNOS的表达和NO的含量。结论:一定剂量的QLT对AIA大鼠的软骨和骨质破坏有抑制作用。     

The comparative arthropathy of fluoroquinolones in dogs.

1. Fluoroquinolone antibiotics are generally only prescribed to paediatric patients on compassionate grounds. This is because they are known to cause lesions in the cartilage of the major diarthroidal joints in immature experimental animals. As dogs are considered to be the most sensitive species, a series of studies was performed to compare the potential for grepafloxacin (a new fluoroquinolone) to cause arthropathy to that of ofloxacin and ciprofloxacin in juvenile (3 month old) beagles. 2. Grepafloxacin was administered once daily to male juvenile dogs at dosages of up to 100 mg/kg/day (intravenously), 60 mg/kg/day (orally) or 30 mg/kg/day (subcutaneously) for 1 week. Blister formation was observed on the surface of the joints in one of the three animals treated with grepafloxacin intravenously at 100 mg/kg/day. No abnormalities were observed at lower dosages or when grepafloxacin was administered orally or subcutaneously, regardless of dose. In animals treated with ofloxacin or ciprofloxacin at dosages of 10-30 mg/kg/day, blister formation or erosion was observed on the surface of joints regardless of dose or route of administration. 3. Histopathological examination of the joint surfaces of affected animals revealed the loss of cartilaginous matrix and chondrocytes, cavitation within the intermediate zone of cartilage accompanied by cartilage fibrillation or chondrocyte clustering, or loss of the surface layer which covers the cavitation (or loss of outer wall of the cavity). These findings were not present in the absence of grossly observed lesions. 4. Absorption following oral administration of grepafloxacin was low. Examination of plasma concentrations of drug following intravenous administration showed that joint toxicity was seen with ofloxacin and ciprofloxacin at maximum concentrations as low as 3.80 and 4.24 mg/l, respectively, while plasma levels of grepafloxacin of up to 11.95 mg/l failed to cause such lesions. When the concentration of grepafloxacin was 18.69 mg/l a single joint lesion was seen. Following subcutaneous administration of grepafloxacin, systemic exposure (area under the curve) of approximately 1.5 times that seen in man was not associated with joint lesions. However, lesions were noted for ofloxacin and ciprofloxacin treated animals at exposures equal to or below those seen in man. Therefore grepafloxacin appeared to have a relatively low potential for joint toxicity; this was not due to lack of penetration into the synovial fluid.     

Autogenous meniscus grafts in articular cartilage defects--an experimental study.

Many methods have been attempted to repair defects in the articular cartilage involving the subchondral bone, but no satisfactory method has yet been established. We performed an experimental study utilizing autogenous meniscus grafts for defects in the articular cartilage involving the subchondral bone. Sixty-two knees of 31 rabbits were thus treated. Gross and histological examinations were performed in animals sequentially sacrificed after 2 to 24 weeks. In gross examinations, the articular surface was smooth and the degenerative changes were slight although the grafted area appeared as a piece of whitish meniscus in all experimental knees. Histologically, 12 weeks were necessary for complete union in the superficial zone of the junction between the grafted meniscus and the subchondral bone. However, the junction in the deep zone was completely united after two weeks. Degenerative changes, such as fibrillation or ulceration were not noted on the surface of the grafted meniscus. The chondrocytes of the meniscus survived for as long as 24 weeks. The autogenous meniscus graft appears to be a promising alternative for defects in the articular cartilage.     

Is leptin the missing link between osteoarthritis and obesity?

The contribution of leptin, as a possible link between osteoarthritis (OA) and obesity, was studied in cartilage and synovial fluid samples obtained from osteoarthritic patients. Its effect on cartilage was evaluated in rats after intraarticular injections of leptin. Leptin levels were measured in the synovial fluid samples by enzyme linked immunosorbent assay; leptin concentrations were correlated with the body mass index. Leptin was strongly expressed in osteophytes and OA cartilage, while, in normal cartilage, few chondrocytes produced leptin. The level of leptin expression was related to the grade of cartilage destruction and was in good relation with those of growth factors as IGF1 and TGFb. Studies in rats showed that intraarticular leptin injection stimulated anabolic functions of chondrocytes and induced the synthesis of leptin, IGF1 and TGFB in cartilage at both the chondrocytes and induced the synthesis of leptin, IGF1 and TGFB in cartilage at both the mRNA and protein levels. In conclusion, leptin may be a link between osteoarthritis and obesity, and may play a key role in cartilage metabolism. Leptin may contribute to the pathophysiology of OA.     

“杜仲-当归”介导Wnt/β-catenin信号转导调控MMP-13表达防治关节炎的作用机制研究

目的 研究“杜仲-当归”介导Wnt/β-catenin信号转导调控MMP13表达防治骨性关节炎（osteoarthritis,OA）的作用机制。方法 取SD大鼠,随机分为Sham组、OA组、OA+补肾组（杜仲40 mg·kg^-1）、OA+活血组（当归40 mg·kg^-1）、OA+补肾活血组（杜仲-当归药液40 mg·kg^-1）、OA+阳性药物组（西乐葆10 mg·kg^-1+奥泰灵1.2 mg·kg^-1）共6组。OA模型制备成功后,各组大鼠给予对应药物治疗,连续给药8周。番红O染色检测软骨组织变化,免疫组织化学检测软骨组织中MMP-13表达,ELISA检测大鼠血清IL-6、IL-8含量,Western blotting检测软骨组织中MMP-3、MMP-9、MMP-13、β-catenin蛋白表达。分离正常SD大鼠软骨细胞,IL-1β（10 ng·mL^-1）干预诱导体外OA炎症模型并进行药物干预。番红O染色检测软骨细胞表型变化,ELISA检测软骨细胞IL-6、IL-8含量,免疫荧光染色检测软骨细胞β-catenin表达,qRT-PCR检测软骨细胞中IL-6、IL-8、MMP-3、MMP-9和MMP-13的mRNA表达,Western blotting检测软骨细胞中MMP-3、MMP-9、MMP-13、β-catenin蛋白表达。结果 药物处理对OA导致的软骨组织损伤有不同程度的修复作用;杜仲-当归可下调血清中IL-6、IL-8水平,下调软骨组织中MMP-3、MMP-9、MMP-13、b-catenin的蛋白表达。与IL-1b组相比,杜仲-当归可提高软骨细胞存活率,改善细胞形态,下调软骨细胞IL-6、IL-8水平,降低软骨细胞中b-catenin荧光强度,并下调软骨细胞中IL-6、IL-8、MMP-3、MMP-9、MMP-13的mRNA表达和MMP-3、MMP-9、MMP-13、b-catenin的蛋白表达。结论 体内、体外试验表明补肾活血中药“杜仲-当归”可以通过促进软骨细胞增殖、调控炎症因子水平、改善软骨基质降解、改善软骨病理损伤起到对OA的防治作用,且作用机制可能与介导Wnt/β-catenin信号转导调控MMP-13表达有关。     

Effect of glucosamine hydrochloride in combination with paracetamol on chondrocyte apoptosis under conditions of systemic steroidal arthritis development in rats

The effect of a combination of glucosamine hydrochloride with paracetamol on the apoptosis of chondrocytes in the articular cartilage of rats with experimental steroidal dystrophy (osteoarthritis) has been studied by hystochemical methods. Untreated control rats are characterized by a significant increase in the fraction of chondrocytes involved in the processes of apoptosis. The treatment of animals by a combination of glucosamine hydrocloride with paracetamol substantially reduced the percentage of apoptic chondrocytes. The pronounced antiapoptic effect of the investigated combination differed but little from the effect of glucosamine hydrochloride alone, but significantly exceeded the antiapoptic activity of paracetamol.     

siRNA沉默ASIC1a基因对佐剂性关节炎大鼠关节软骨细胞凋亡的影响研究

目的:探讨小分子干扰RNA(siRNA)技术诱导佐剂性关节炎(adjuvant-induced arthritis,AA)大鼠关节软骨细胞中ASIC1a表达沉默对细胞凋亡的影响。方法:通过化学合成法合成特异性荧光短链ASIC1asiRNA-FAM,使用Lipo-fectamine 2000转染试剂盒将ASIC1asiRNA转染入关节软骨细胞,采用荧光显微镜、流式细胞术、实时荧光定量PCR(q-RT-PCR)及WesternBlot法检测siRNA转染效率及其对ASIC1amRNA和蛋白表达的抑制作用。同时采用An-nexin-V/PI流式细胞术检测各组细胞凋亡情况。结果:ASIC1asiRNA能成功转入软骨细胞,转染后AA大鼠关节软骨细胞中ASIC1amRNA表达显著低于对照组(P<0.01),最大抑制率为85.4%;Western Blot结果显示,转染特异性siRNA后ASIC1a蛋白表达明显低于对照组(P<0.01)。Annexin-V/PI流式细胞术结果表明,与模型组相比,siRNA-3转染引起ASIC1a表达沉默后AA大鼠软骨细胞凋亡明显减少。结论:siRNA介导的AA大鼠关节软骨细胞ASIC1a表达沉默模型是研究酸敏感离子通道对软骨细胞代谢影响的可靠模型,siRNA-3转染对胞外酸化刺激条件下AA大鼠关节软骨细胞凋亡的保护作用可能与其调节的表达有关。     

豆腐果苷对骨关节炎大鼠软骨和滑膜组织影响

目的研究豆腐果苷对骨关节炎大鼠软骨结构和滑膜组织的影响。方法碘乙酸钠注射 SD雄性大鼠膝关节造模成功后,随机区组分组法分为三组,即假手术组、模型组、豆腐果苷 50 mg·kg.1·d.1组。豆腐果苷灌胃 21 d后,取大鼠膝关节制成组织切片, HE染色观察膝关节软骨和滑膜病理变化,并进行评分;番红固绿染色观察大鼠膝关节软骨病理变化,并进行 Mankin评分。研究起止时间为 2019年 12月至 2020年 7月。结果相对于假手术组,模型组大鼠膝关节软骨和滑膜均受到不同程度损伤,滑膜病理评分显著升高［( 6.88±0.83)分比( 0.50±0.53)分］(P<0.01)且软骨结构、软骨细胞和番红固绿染色的 Mankin评分也显著升高［分别是( 3.88±0.83)分比( 0.50±0.53)分,(1.75±0.46)分比(0,.25±0.46)分,(2.38±0.74)分比( 0.38±0.52)分］(P<0.01)。然而,连续给予豆腐果苷灌胃 21 d后,相对于模型组,大鼠的关节软骨结构和滑膜组织损伤程度均有显著改善,膝关滑膜病理评分显著降低［(3.50±0.53)分比(6.88±0.83)分］(P<0.01)且软骨结构、软骨细胞和番红固绿染色的 Mankin评分也显著降低［分别为( 1.63±0.52)分,(1.13±0.64)分,(0.88±0.64)分］(P<0.0,5)。结论豆腐果苷可减轻骨关节炎大鼠膝关节软     

Influence of short-term aluminum exposure on demineralized bone matrix induced bone formation

The effects of aluminum exposure on bone formation employing the demineralized bone matrix (DBM) induced bone development model were studied using 4-week-old Sprague-Dawley rats injected with a saline (control) or an aluminum chloride (experimental) solution. After 2 weeks of aluminum treatment, 20-mg portions of rat DBM were implanted subcutaneously on each side in the thoracic region of the control and experimental rats. Animals were killed 7, 12, or 21 days after implantation of the DBM and the developing plaques removed. No morphological, histochemical, or biochemical differences were apparent between plaques from day 7 control and experimental rats. Plaques from day 12 control and experimental rats exhibited cartilage formation and alkaline phosphatase activity localized in osteochondrogenic cells, chondrocytes, osteoblasts, and extracellular matrix. Unlike the plaques from control rats that contained many osteoblastic mineralizing fronts, the plaques from the 12-day experimental group had a preponderance of cartilaginous tissue, no evidence of mineralization, increased levels of alkaline phosphatase activity, and a reduced calcium content. Plaques developing for 21 days in control animals demonstrated extensive new bone formation and bone marrow development, while those in the experimental rats demonstrated unmineralized osteoid-like matrix with poorly developed bone marrow. Alkaline phosphatase activity of the plaques continued to remain high on day 21 for the control and experimental groups. Calcium levels were significantly reduced in the experimental group. These biochemical changes correlated with histochemical reductions in bone calcification. Thus, aluminum administration to rats appears to alter the differentiation and calcification of developing cartilage and bone in the DBM-induced bone formation model and suggests that aluminum by some mechanism alters the matrix calcification in growing bones.     

吡格列酮可抑制胶原诱导性关节炎大鼠的骨吸收

目的探讨吡格列酮是否可抑制胶原诱导性关节炎(CIA)大鼠的炎症性骨吸收。方法分别用肿瘤坏死因子(TNFα)拮抗剂(注射用重组人Ⅱ型肿瘤坏死因子受体抗体融合蛋白,TNFR Ⅱ-Fc)腹腔注射,低、中、高剂量(3、10、30mg.kg-1.d-1)吡格列酮灌胃治疗CIA大鼠3周。比较各治疗组与正常对照组、模型对照组的病理差异、骨代谢指标——骨保护素(OPG)、核因子κB受体活化因子配体(RANKL)及TNFα的蛋白水平差别。用酶联免疫吸附法(ELISA)、免疫组织化学、蛋白印迹法等方法检测OPG、RANKL及TNFα的蛋白表达。结果模型对照组后踝关节炎性细胞浸润、滑膜组织增生及软骨不同程度破坏;各治疗组关节炎症和滑膜增生不同程度改善,无软骨及骨破坏。相比模型对照组,各治疗组血清及软骨中OPG水平明显增高,而血清中TNFα及软骨中RANKL水平明显降低(P<0.05)。相比低剂量吡格列酮治疗组,高剂量吡格列酮治疗组OPG水平较高,而TNFα及RANKL水平较低(P<0.05)。相比TNFα拮抗剂治疗组,高剂量吡格列酮治疗组软骨中OPG水平较高,而RANKL水平较低(P<0.05)。结论吡格列酮可通过下调CIA大鼠血清中的TNFα及关节软骨中的RANKL,上调关节软骨、滑膜及血清中OPG的蛋白表达,起到抑制CIA大鼠的炎症性骨吸收的作用;并且有随剂量增大而增强的趋势,高剂量吡格列酮治疗时此作用可能稍强于TNFRⅡFc。     

Effects of SL-1010 (sodium hyaluronate with high molecular weight) on experimental osteoarthritis induced by intra-articularly applied papain in guinea pigs]

Effects of SL-1010 on the experimental osteoarthritis (OA) produced by intra-articular injection of papain, proteolytic enzyme, in the knee joint of the guinea pigs were histologically and biochemically investigated. In addition, experimental conditions to produce OA in guinea pig knee joint were also examined, since papain-induced OA has been mainly studied in rabbits. Six weeks after intra-articular injection of papain (1%, 0.1 ml), there were inflammatory reactions of the synovial membrane, degenerative changes in chondrocytes and the matrix of the articular cartilage, a decrease in the Safranin-O staining intensity and lowering of sulfated glycosaminoglycan. Electronmicroscopic observations revealed that the amorphous layer had disappeared and large bundles of unit collagen fibers and larger collagen fibers had appeared in the cartilage matrix. In the OA model, SL-1010 reduced the inflammatory reactions of the synovial membrane, inhibited development of degenerative changes in chondrocytes and the matrix of the articular cartilage and recovered the Safranin-O staining intensity. The sulfated glycosaminoglycan contents in the cartilage was significantly increased in the SL-1010-treated group, compared with the control group. The electromicroscopically observed charges in the papain-injected knee joint of the control group were rarely detected in the SL-1010-treated group. These results suggest that SL-1010 inhibits degenerative changes in the chondrocytes and the matrix probably by reducing synovial inflammation and protection of the cartilage in the OA model of guinea pigs.     

丹参多酚酸对佐剂型关节炎大鼠的治疗作用

目的观察丹参多酚酸(Salvianolic acids)对大鼠佐剂型关节炎的治疗作用。方法大鼠予注射弗氏完全佐剂造模,测量大鼠后足肿胀程度,采用屈、伸关节疼痛试验评分法记录大鼠足趾疼痛指数,HE染色观察关节病理学改变。结果与正常组比较,模型组大鼠继发侧足肿胀程度和足趾疼痛指数明显升高。踝关节关节腔内及周围组织有大量的炎性细胞浸润;关节软骨受损、破坏。与模型组比较,丹参多酚酸连续灌胃治疗后,降低了大鼠继发侧足肿胀程度和足趾疼痛指数,踝关节腔及周围组织炎性浸润减少,关节软骨破坏程度减轻。结论丹参多酚酸能够减轻佐剂关节炎大鼠的足趾肿胀度、降低足趾疼痛指数,改善踝关节病理组织形态。提示丹参多酚酸对佐剂型关节炎大鼠具有一定的治疗作用。     

DLTH通过调节免疫功能和软骨降解从而抑制RA的作用

目的以壳聚糖-甘油-硼砂为载体,制备新型的,可注射的,具有缓释作用的地塞米松温敏凝胶(dexamethasone-loaded thermosensitive hydrogel,DLTH)。观察DLTH对类风湿性关节炎(rheumatoid arthritis,RA)免疫调节和软骨保护作用。方法将30只大鼠分为对照组、模型组和DLTH组。对模型组和DLTH组构建RA模型。从d 12,DLTH组双侧膝关节内给药40μL DLTH(即1 mg·kg^-1地塞米松),每周两次,给药3周后取材。ELISA检测血清细胞因子IL-1β和TNF-α的表达,脾组织切片行HE染色,膝关节切片进行甲苯胺蓝染色和免疫组化分析,PCR检测相关炎症因子和降解酶变化。结果与模型组相比,DLTH组血清炎症因子及脾脏病理性变化明显减轻。DLTH可以显著抑制脾脏炎症因子表达和调整Th1/Th2、Th17/Treg失衡状态。同时,对软骨进行一系列分析发现,DLTH可以显著改善RA引起的软骨破坏现象,抑制软骨细胞中炎症因子和相关降解酶的表达。结论DLTH对RA具有明显的免疫调节和软骨保护作用。     

酸敏感离子通道阻断剂amiloride对佐剂性关节炎大鼠关节软骨损伤的影响

目的探讨酸敏感离子通道(ASICs)阻断剂amiloride对佐剂性关节炎(AA)大鼠关节软骨损伤的影响。方法将大鼠随机分成正常组,AA模型组,amiloride50、100、150mg·kg-1组,地塞米松(0.2mg·kg-1)对照组。弗氏完全佐剂(CFA)致炎后第10天起,AA大鼠出现继发性炎症,此时腹腔注射amiloride、地塞米松,正常组与模型组灌胃等容量的无菌注射用水,连续7d。实验结束后,体外用激光共聚焦显微镜检测细胞Ca2+浓度,分析胞外低pH值和ASICs阻断剂amiloride对关节软骨细胞内钙离子浓度([Ca2+]i)的影响;用足容积法测量继发侧足肿胀度,用免疫组织化学方法分析大鼠关节软骨Ⅱ型胶原的表达,用alcian蓝染色检测大鼠关节软骨蛋白多糖的变化。结果细胞外pH(pH6.5)可使关节软骨细胞内Ca2+水平短暂性升高,amiloride能明显抑制pH6.5诱导的关节软骨胞内Ca2+水平;各用药组能明显升高AA大鼠关节软骨细胞基质成分Ⅱ型胶原和蛋白多糖表达量。结论amiloride可能通过阻断酸敏感离子通道减轻AA大鼠关节软骨破坏,发挥关节保护作用。     

Expression of PDCD5, a novel apoptosis related protein, in human osteoarthritic cartilage

INTRODUCTIONOsteoarthritis (OA) is a degenerative joint diseasecharacterized by the progressive erosion of articularcartilage as well as the thickening of subchondral bone[1].The pathogenesis of OA is poorly understood[2,3], how-ever it is believed that both an imbalance between carti-lage degradation and synthesis that leads to extracellularmatrix damage as well as a severe loss of chondrocytesin the articular cartilage participate in the process. Theloss of chondrocytes is at least pa…