单侧后牙缺失对大鼠髁突软骨中蛋白激酶C-δ和caspase-12表达的影响

Effect of unilateral posterior tooth loss on expression of protein kinase C-δand caspase-12 in condylar cartilage in rats

目的探讨大鼠单侧后牙缺失后,髁突软骨细胞中蛋白激酶C-δ和caspase-12的表达变化及其在凋亡反应中的作用。方法3周龄雄性SD大鼠96只,随机分为实验组、对照组各4组,实验组拔除左侧所有磨牙,对照组无拔牙处理,于拔牙后第1天、7天、14天、28天处死并取材髁突软骨。HE染色观察髁突软骨细胞的病理改变,RT-PCR法检测蛋白激酶C-δ和caspase-12在软骨细胞中的表达。结果HE染色显示拔牙后,实验组髁突软骨出现细胞排列紊乱,纤维断裂,细胞核固缩,核空泡性变等退行性改变。RT-PCR结果显示,实验组左、右侧的蛋白激酶C-δ和caspase-12含量均高于对照组,实验组右侧蛋白激酶C-δ和caspase-12含量逐渐降低。结论单侧后牙缺失导致大鼠双侧髁突受力不均,诱导软骨细胞启动凋亡反应,蛋白激酶C-δ被激活,caspase-12的表达增强。

Objective To investigate the expression of protein kinase C-δand caspase-12 in condylar cartilage after loss of unilateral posterior tooth in rats and their role in apoptosis.Methods Ninety-six three-week-old SD rats were randomly divided into 4 experiment groups and 4 control groups.The rats in the experimental groups were extracted all of the left posterior teeth,and that in control groups received no treatment.The rats were killed after 1 day,7 days,14 days,28 days.The condylar cartilage was taken completely.HE staining was used to observe the pathological change of condylar cartilage.The expression of protein kinase C-δand caspase-12 in articular cartilage was detected by RT-PCR.Results HE staining showed that condylar cartilage of the experimental group showed degenerative changes such as disordered cell arrangement,fiber fracture,nuclear contraction and vacuolar degeneration of the nucleus after tooth extraction.The expression of protein kinase C-δand caspase-12 in both sides of experimental group is higher than that of control group.RT-PCR showed that the content of protein kinase C-δand caspase-12 of right condyle cartilages in experimental groups reduced.Conclusion The loss of unilateral posterior tooth resulted in uneven stress on the condylar on both sides of the rats and induced apoptosis response.The protein kinase C-δwas activated and the expression of Caspase-12 was promoted.