慢性不可预见性应激致大鼠髁突软骨组织学变化的自然转归  

Natural reversal of mandibular condylar cartilage histological damage caused by chronic unpredictable moderate stress in rats

作　　者：刘杨 刘晓波 李强[1] 赵雅娟 陈永进 LIU Yang;LIU Xiaobo;LI Qiang;ZHAO Yajuan;CHEN Yongjin(State Key Laboratory of Military Stomatology,National Clinical Research Center for Oral Diseases,Shaanxi International Joint Research Center for Oral Diseases,Department of General Dentistry and Emergency,School of Stomatology,Fourth Military Medical Uni-versity,Xi'an 710032,China;Department of Stomatology,Guangzhou Hospital of Integrated Traditional and West Medicine,Guangzhou 510800,China)

机构地区：[1]军事口腔医学国家重点实验室国家口腔疾病临床医学研究中心陕西省口腔疾病国际联合研究中心第四军医大学口腔医院急诊与综合临床科,陕西西安710032 [2]广州市中西医结合医院口腔科,广东广州510800

出　　处：《口腔疾病防治》2023年第5期312-320,共9页Journal of Prevention and Treatment for Stomatological Diseases

基　　金：国家自然科学基金项目(82071136);军事口腔医学国家重点实验室基金(2019ZA02);陕西省自然科学基础研究计划(2022JQ-785)。

摘　　要：目的探讨慢性不可预见性应激引起的颞下颌关节髁突软骨的组织学受损的转归,为颞下颌关节紊乱病的防治提供实验依据。方法本动物实验经第四军医大学口腔医院实验动物管理伦理委员会批准(批准号:2020伦审字081号)。将60只雄性SD大鼠随机分为空白对照组、应激组、应激去除2周组、应激去除4周组、应激去除8周组。对大鼠施加的慢性不可预见性应激(chronic unpredictable moderate stress,CUMS)包括24 h潮湿垫料、12 h倾斜饲养、4 h噪音、昼夜颠倒、强迫浸水、夹尾、束缚应激,持续8周;在去除应激2周、4周、8周后观察其血清学、行为学以及髁突软骨组织学与超微结构的变化,其中采用酶联免疫法观察大鼠的血清促肾上腺皮质激素(adrenocorticotropic hormone,ACTH)和皮质酮(corticosterone,CORT)水平的变化,采用糖水偏好实验和强迫游泳实验观察大鼠抑郁样情绪的行为学变化,运用免疫组织化学染色法和Western blot法检测髁突软骨白细胞介素-1α(interleukin-1α,IL-1α)和基质金属蛋白酶-3(matrix metalloproteinases-3,MMP-3)的表达。结果应激组在CUMS刺激持续8周末时,与对照组相比大鼠血清中CORT和ACTH水平增高(P<0.01),行为学表现为摄糖减少、强迫游泳实验中“不动”时间延长(P<0.01),说明出现了明显的快感缺失、抑郁、绝望情绪,证明CUMS模型建立成功;并且髁突软骨表现出明显的退行性改变,软骨表面胶原纤维排列紊`乱,蛋白多糖合成减少;髁突中的IL-1α和MMP-3在各层软骨的胞内和细胞外基质中均有表达,且表达水平升高(P<0.01)。应激去除2周后CORT和ACTH血清学水平下降,但高于对照组(P<0.01),行为学检测与对照组相比仍有差异(P<0.01);髁突软骨表面仍可看到松解的胶原纤维,增殖层内可见一些游离细胞区;髁突中的IL-1α和MMP-3在各层软骨的表达较应激组降低,但仍高于对照组(P<0.01)。应激去除4周后,CORT和ACTObjective To investigate the histological damage recovery of temporomandibular joint condylar cartilage caused by chronic unpredictable moderate stress, aiming to provide an experimental basis for the prevention and treatment of temporomandibular disorder.Methods This animal experiment was approved by the Laboratory Animal Ethical Inspection, School of Stomatology, The Fourth Military Medical University(No. 2020081). 60 male SD rats were randomly divided into control group, stress group, and 2-, 4-and 8-week post-stress recovery groups. Rats were subject-ed to chronic unpredictable moderate stress(CUMS) for 8 weeks including damp sawdust for 24 hours, tilted cage for 12hours, noise for 4 hours, light/dark cycle reversal, water immersion, tail clamp, and restraint stress. The serum assess-ment, behavioral tests, histological and ultrastructural observation were performed 2-, 4-and 8-weeks after stress factorswere removed. Serum levels of adrenocorticotropic hormone(ACTH) and corticosterone(CORT) were determined withELISA. The sucrose preference test(SPT) and the forced swim test(FST) were used to assess the depressive-like behav-ior. The expression level of interleukin-1α(IL-1α) and matrix metalloproteinases-3(MMP-3) were determined by Immu-nohistochemistry and Western blot.Results At the end of 8 weeks of CUMS, the serum levels of CORT and ACTHwere significantly higher in stress group compared with control group(P<0.01). The sucrose preference decreased sig-nificantly and the immobility time increased significantly in the stressed rats compared with those in the control group,indicating a successful establishment of CUMS. The condylar cartilage showed significant degenerative changes, withdisorganized collagen fibers and reduced proteoglycan synthesis on the cartilage surface. IL-1α and MMP-3 were ex-pressed in the intracellular and extracellular matrix of the condylar cartilage, and their expression levels were increased(P<0.01). After 2 weeks of stress removal, the serum levels of CORT and ACTH were decrease

关 键 词：心理应激 慢性不可预见性应激 颞下颌关节紊乱症 抑郁样情绪 髁突软骨 白细胞介素-1Α 基质金属蛋白酶-3 自然转归 

分 类 号：R78[医药卫生—口腔医学]