脊髓损伤大鼠体内P物质变化对成骨细胞分化的影响

目的探讨P物质（SP）对脊髓损伤（SCI）大鼠骨髓间充质干细胞（MSCs）源性成骨细胞分化的影响及机制。方法取SCI大鼠双侧胫骨、股骨冲洗髓腔后收集细胞悬液,进行骨髓MSCs源性成骨细胞诱导培养。观察SP不同浓度（10^-12、10^-10、10^-8、10^-7、10^-6M）、不同作用时间（1、2、3周）对成骨细胞碱性磷酸酶（ALP）活性的影响,观察SP与Spantide（SP抑制剂）、L703606（NK1受体抑制剂）配伍作用后细胞ALP活性。结果与对照组比较,不同浓度的SP作用后细胞ALP活性均明显降低,10^-8M浓度时最低,P均〈0.05;随着作用时间的延长ALP活性降低明显,P〈0.05。与SP单独作用比较,SP与Spantide和L703606配伍后细胞ALP活性均明显升高,P〈0.05。结论SP通过NK1受体对成骨细胞的分化产生影响;SP抑制成骨细胞的分化,使成熟的成骨细胞减少,可导致骨质疏松的发生。

Effects of substance P on the cell differentiation of osteoblasts in spinal cord injury rats

Objective To investigate the effects and mechanism of substance P（SP）on the cell differentiation of osteoblasts derived from mesenchymal stem cells（MSCs） in spinal cord injury（SCI）rats.Methods MSCs from bilateral marrow cavities of tibiae and femurs in SCI rats were cultured under control mediums and induced to become osteoblasts.The ALP activity of osteoblasts were observed after treated with different concentrations（10^-12,10^-10,10^-8,10^-7,10^-6M） of SP and for different time（1,2,3 week）,also were also observed after the treatment of SP and Spantide（SP blocking agent）,L703606（NK1 receptor blocking agent）.Results Compared with the control group,the ALP activity of osteoblasts decreased after treated with different concentrations of SP,and reached the lowest at the concentration of 10^-8 M,all P0.05.The ALP activity decreased significantly with the extension of time,P〈0.05.The decreased cell differentiation induced by SP was inhibited by spantide and L703606 respectively,P0.05.Conclusions NK1 receptors are the target receptors of SP inducing differentiation in osteoblasts.SP can inhibit the differentiation of osteoblasts,decrease the number of mature osteoblasts,and cause osteoporosis.