JNK、p38 MAPK在移植静脉血管重塑过程中的表达研究

The expression and significance of JNK and p38 MAPK in vascular remodeling of autogenous vein graft

目的 研究c Jun氨基末端激酶 (JNK)和p38蛋白激酶 (MAPK)在移植静脉血管重塑过程中的表达。方法 Wistar大鼠 80只 ,建立自体移植静脉模型 ,术后随机分为 6h ,1、3、7,1 4、2 8、4 2、5 6d等 8组 ,于相应时点取材 ,逆转录聚合酶链反应 (RT PCR)检测JNK和p38MAPK的mRNA表达 ,Western蛋白印迹检测JNK和p38的蛋白产物及磷酸化蛋白产物表达 ,原位杂交和免疫组化方法定位mRNA及蛋白产物表达 ,脱氧核苷酸转移酶末端标记法 (TUNEL)检测血管平滑肌细胞 (VSMC)凋亡的变化。结果 移植静脉术后 6h ,JNK和p38的mRNA表达增强 ,在术后 1 4d达到高峰 ,表达值分别为(2 6± 1 0 ) %和 (5 9± 2 6 ) %,与各时点比较差异有统计学意义 (P <0. 0 1 )。JNK、p38的蛋白产物表达在1 4～ 2 8d达高峰 ,在 5 6d时仍维持一定表达量 (1 .4～ 1 . 2 )。原位杂交及免疫组化提示阳性表达多位于移植血管中层或增生内膜中的血管平滑肌细胞 (VSMC) ,p38与凋亡呈正相关 (r =0 . 892 2 ,P <0. 0 1 )。结论 JNK和p38MAPK通路的激活是移植静脉内膜增生以及血管重塑的关键环节 ,可能成为新的治疗靶点。

Objective To investigate the expression of c-Jun N-terminal kinase (JNK) and p38MAPK in autogenous vein graft during vascular remodeling. Methods Autogenous vein graft model was established in 80 Wistar rats. Vein graft samples were harvested at 6th hour, day 1, day 3, day 7, day 14, day 28, day 42 and day 56. Gene expression of JNK and p38MAPK were measured by reverse transcription-PCR and in situ hybridization. Western blot and immunohistochemistry were used to detect the protein expression and phosphorylation of JNK and p38 MAPK. Apoptosis of VSMCs was studied by TUNEL. Results The expression of JNK mRNA and p38 mRNA reached the highest level on the second week (26±10)% and (59±26)% respectively, P<0.01 when compared to other groups). The expression of JNK and p38 reached the peak during days 14 to 28 and decreased gradually. The positive cells were mostly vascular smooth muscle cells located in media and intimal hyperplasia of vein graft. There was a positive relationship between p38 and apoptosis (r=0.8922, P<0.01). Conclusion JNK and p38 MAPK system were activated in autogenous vein graft.