摘要
目的观察过量氟对大鼠骨骼I型胶原mRNA表达的影响和对大鼠骨骼中胶原纤维性状的作用。方法将雄性Wistar大鼠随机分为6组,每组10只,分别为给氟0.5、1、2个月组及相应的对照组。给氟组饮用含221mg/LNaF的含氟水,对照组饮用蒸馏水。制备α1(Ⅰ)胶原cDNA探针,采用cDNA-mRNA原位杂交方法,检测大鼠骨组织中I型胶原mRNA的改变。采用苦味酸-天狼星红偏振光染色法对骨组织中胶原纤维进行观察。结果cDNA-mRNA原位杂交显示,大鼠给氟0.5个月后,I型胶原mRNA水平上升,但在给氟1个月及2个月时,阳性信号减弱。苦昧酸-天狼星红偏振光观察显示在肱骨、股骨、肋骨等骨组织中,胶原纤维发生断裂、变短、变细、排列紊乱,含量下降。结论过量氟对骨I型胶原mRNA表达有短期增强作用,继而抑制I型胶原mRNA合成。胶原mRNA水平下降可能是氟骨症胶原蛋白水平下降的原因之一。过量氟可导致大鼠I型胶原纤维正常结构破坏,交联下降。
Objective To investigate the effects of excessive fluoride on the expression of typeⅠcollagen mRNA and the characteristics of collagenous fibers distribution,cross linking and morphology of collagen fibers in ratsbone.Methods Male Wistar rats were randomly divided into6groups,10rats per group,including0.5-month,1-month and2-month fluoride-exposure group drinking water containing221mg/L NaF and related control group drinking distilled water.TypeⅠcollagenα 1 (Ⅰ)cDNA probe was prepared and cDNA-mRNA in situ hybridization were used to detect the typeⅠcollagen mRNA in ratsbone.Pi-crosirius-polarization method was used to observe the collagen fibers in ratsbone.Results In situ hybridization showed that after0.5-month treatment with fluoride,th e levels ofα 1 (Ⅰ)collagen gene expression in rat bone increased,but decreased after1-month and2-months treatment compared with that without fluoride treatment.In bone tissue of humerus,thigh and rib of fluo-ride-treated rat the collagen fibers became shorter and thinner,the normal order of fibers was damaged,more broken collagen fibers were found.Conclusion In the early stage,typeⅠcollagen gene expression was enhanced by fluoride,but then synthesis of typeⅠcollagen mRNA was inhibited after further fluoride-treatment.The down-regulation of mRNA expression might lead to the decrease of the collagen level in fluorosis of bone.Excessive fluoride could damage the structure of collagen fiber and de-crease cross-linking.
出处
《环境与健康杂志》
CAS
CSCD
北大核心
2003年第4期204-206,共3页
Journal of Environment and Health
基金
国家自然科学基金资助项目(39730390)
关键词
氟化物中毒
骨和骨组织
胶原Ⅰ型
原位杂交
Fluorides poisoning
Bone and bones
Collagen type I
In situ hybridization
