STC1及钙、磷离子在氟中毒致大鼠肾损伤中的作用

摘要

Objective To observe the changes of stanniocalcin 1(STC1) , calcium and phosphorus ions in renal tissue of rats with fluorosis ,and to explore the effects of STC1 on the fluorosis-induced renal injury. Methods 24 male Sprague-Dawley rats were divided into 4 groups:control group(intraperitoneal injection of normal saline) , low-fluoride group (intraperitoneal injection of sodium fluoride 5 mg/kg) ,medium-fluoride group (intraperitoneal injection of sodium fluoride 10 mg/kg) and high-fluoride group (intraperitoneal injection of sodium fluoride 20 mg/kg). Intraperitoneal injection were performed once every 48 h,and the rats were sacrificed 16 weeks after modeling. Immunohistochemistry and reverse transcriptase-polymerase chain reaction(RT-PCR) were employed to detect the protein and mRNA expression of STC1 in renal tissue,respectively. Calcium and phosphorus ions contents in renal tissue were measured. Results STC1 protein was mainly located in the proximal convoluted tubule at the cortico-medullary junction. Protein and mRNA expression levels of STC1 in renal tissue of rats in fluoride exposure groups were all higher than those in control group(P<0. 05) ,and STC1 expression level was increased with the fluoride concentration increasing. Calcium contents in renal tissue of rats in fluoride exposure groups were all higher than those in control group(P<0. 05). Phosphorus contents in renal tissue of rats in low-fluoride group and high-fluoride group were significantly lower than those in control group(P<0. 05), while those in medium-fluoride group demonstrated no significant difference when compared with the control group(P>0. 05) , and were higher than those in low-fluoride group and high-fluoride group(P<0. 05). Conclusion STCl probably participates in the renal injury of rats with fluorosis,and the injury mechanism may be related to calcium and phosphorus ions metabolic imbalance.%目的 观察斯钙素蛋白1(STC1)及钙、磷离子在氟中毒大鼠肾组织中的变化,探讨STC1在氟中毒肾损伤中的作用.方法 将24只雄性Sprague-Dawley大鼠分为4组:对照组(腹腔注射生理盐水)、低氟组(腹腔注射氟化钠5 mg/kg)、中氟组(腹腔注射氟化钠10 mg/kg)及高氟组(腹腔注射氟化钠20 mg/kg),每48 h注射1次,建模16周后处死大鼠.采用免疫组织化学法及逆转录聚合酶链反应(RT-PCR)分别检测肾组织STC1蛋白及mRNA的表达水平,并检测肾组织内钙、磷离子的含量.结果 STC1蛋白主要定位于大鼠皮髓交界的近曲小管,染氟组大鼠肾组织STC1蛋白及mRNA表达水平均显著高于对照组(P<0.05),随着染氟浓度的增加,STC1的表达水平增加;染氟组大鼠肾组织中钙含量均比对照组增多(P<0.05);低氟组及高氟组大鼠肾组织磷含量明显低于对照组(P<0.05),而中氟组大鼠肾组织磷含量较低氟组及高氟组高(P<0.05),且与对照组比较,差异无统计学意义(P>0.05).结论 STC1可能参与了氟中毒大鼠的肾损伤,而该损伤机制可能与钙、磷离子代谢失衡有关.