特发性甲状旁腺功能减退症对大鼠牙萌出的影响  

Effects of idiopathic hypoparathyroidism on tooth eruption of rats

作　　者：赵迪芳 关淑元 樊怡[2] 郑黎薇[1] Zhao Difang;Guan Shuyuan;Fan Yi;Zheng Liwei(Department of Pediatric Dentistry,West China Hospital of Stomatology,Sichuan University&State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases,Chengdu 610041,China;Department of Conservative Dentistry and Endodontics,West China Hospital of Stomatology,Sichuan University&State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases,Chengdu 610041,China)

机构地区：[1]四川大学华西口腔医院儿童口腔科,口腔疾病研究国家重点实验室,国家口腔疾病临床医学研究中心,成都610041 [2]四川大学华西口腔医院牙体牙髓病科,口腔疾病研究国家重点实验室,国家口腔疾病临床医学研究中心,成都610041

出　　处：《中华口腔医学杂志》2021年第9期880-891,共12页Chinese Journal of Stomatology

基　　金：国家自然科学基金(81771033,81800928)。

摘　　要：目的通过建立特发性甲状旁腺功能减退症(idiopathic hypoparathyroidism,IHP)动物模型,探究生长发育期甲状旁腺功能减退对牙萌出及牙釉质发育的影响,以及IHP影响牙萌出的作用机制。方法选择出生后第7天(postnatal 7,P7;P14、P25、P38含义以此类推)的SD大鼠共48只,采用随机数字表法分为IHP组和假手术组,每组24只,用纳米碳负显影技术对IHP组大鼠行双侧甲状旁腺切除术(parathyroidectomy,PTX),对假手术组大鼠应用同样技术但不行PTX,术后检测大鼠血清钙、磷、甲状旁腺激素(parathyroid hormone,PTH)浓度,建立IHP模型。P14、P25及P38时分别处死大鼠并收集下颌骨样本,每组每个时点6只,通过显微CT分析下颌第三磨牙根方牙槽骨的骨微结构参数、下颌第三磨牙萌出高度及牙釉质体积。制备组织学石蜡切片,通过免疫组织化学染色检测大鼠第三磨牙周围牙槽骨中成骨标志物Runt相关转录因子2(runt‐related transcription factor 2,RUNX2)、成骨细胞特异性转录因子(osterix,OSX)的分布及表达,抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP)染色检测破骨细胞数量。分离下颌第三磨牙,显微硬度仪检测牙釉质硬度,扫描电镜观察牙釉质显微结构。另收集P14大鼠下颌骨,每组6只,体外分离培养牙囊细胞进行细胞集落形成实验。诱导牙囊细胞成骨向分化后用碱性磷酸酶染色和茜素红染色检测矿化程度。提取下颌骨组织及牙囊细胞mRNA,实时荧光定量PCR检测与成骨、破骨细胞分化和功能有关的基因及甲状旁腺激素受体-1(parathyroid hormone receptor 1,PTH1R)基因的表达。结果通过双侧PTX成功建立大鼠IHP模型,术后IHP组大鼠血清钙及PTH浓度显著降低、血清磷浓度显著升高(P<0.01)。IHP组下颌第三磨牙牙釉质体积[(4.58±0.24)mm^(3)]较假手术组[(5.22±0.46)mm^(3)]显著减小(P<0.05),牙釉质表面釉柱结构排列紊乱,显微硬度[(167.76±21.86)MPa]Objective To explore the effects of reduced parathyroid function in early growth and development on tooth eruption and enamel development by establishing an animal model of idiopathic hypoparathyroidism(IHP)and to explore the mechanism of IHP affecting tooth eruption with a view to provide experimental basis for early diagnosis and clinical treatment of IHP.Methods Forty-eight SD rats at postnatal day 7 were randomly and equally divided into sham operation group and IHP group.The bilateral parathyroidectomy(PTX)was performed by using carbon nanoparticles technique to establish an IHP rat model,while no parathyroids were removed in the sham operation group using the same technique.Serum was extracted after surgery,serum calcium,serum phosphorus,and serum parathyroid hormone(PTH)concentrations were detected in order to verify the success of the modeling.At postnatal day 14,day 25 and day 38(P14,P25 and P38)the rats were sacrificed to collect the mandible samples(six from each group)and to analyze the volume of enamel,the height of the tooth eruption and the bone microarchitecture parameters of the root-oriented alveolar bone of mandibular third molar quantitatively by micro-CT scanning.Histological sections were prepared.The distribution and expression levels of osteoblast differentiation markers runt-related transcription factor 2(RUNX2)and osterix(OSX)in the alveolar bone around the third molar were detected by immunohistochemical staining and the osteoclast activity was detected by tartrate-resistant acid phosphatase(TRAP)staining.After each of the third molars was isolated,the microhardness of the enamel was measure by using a microhardness tester and the enamel microstructure was photographed by using scanning electron microscope.Primary dental follicle stem cells were isolated from other six mandibulars from each group at P14 and cultured in vitro.The cell proliferation activity was tested by cell colony forming units detection.After induction of dental follicle stem cells into osteogenic differentiation,the

关 键 词：受体 甲状旁腺激素 1型 甲状旁腺功能减退症 牙萌出 骨改建 牙囊细胞 

分 类 号：R582.2[医药卫生—内分泌]