目的:探讨不同剂量尼古丁对大鼠正畸牙移动过程中牙周组织内前列腺素-2(PGE-2)表达的影响。方法:将100只SD大鼠(SPF级)随机分为A、B、C、D 4组(n=25),统一用50 g力牵拉一侧上颌第一磨牙向近中移动,A组每日腹腔注射0.1 mL生理盐水,B、C、D 3组每天分别腹腔注射0.5、0.75、1 mg/kg尼古丁酒石酸溶液;分别于加力1、3、5、7、14 d各时间点,从每组中各随机抽取5只大鼠,处死后取其上颌骨组织块制作石蜡切片,HE染色观察牙周组织变化并进行破骨细胞计数,免疫组化染色法检测PGE-2在牙周组织中的表达水平。结果:与对照组相比,3种不同剂量尼古丁组的破骨细胞数均明显增高,且随着尼古丁剂量的增大而增加,各组间两两相比P<0.05,加力5 d时各组破骨细胞数均达到峰值;免疫组化染色显示,各剂量尼古丁干预组的PGE-2水平均明显升高,且随着尼古丁剂量的增大而增强,相同加力条件下,各组间两两相比P<0.05,加力5 d时各组的PGE-2表达量均达到峰值。结论:尼古丁可剂量依赖性地促进正畸移动牙牙周组织中PGE-2的表达,并使破骨细胞数增加。 Objective: To investigate the effect of different doses of nicotine on the expression of prostaglandin-2 (PGE-2) in periodontal tissues during orthodontic tooth movement in rats. Methods: One hundred SD rats (SPF grade) were randomly divided into A, B, C, D 4 groups (n = 25) The rats in group B, C and D were intraperitoneally injected with 0.5, 0.75, 1 mg / kg nicotine tartaric acid solution respectively at each time points of 1, 3, 5, 7, Five rats were randomly selected from each group. After sacrifice, the paraffin sections of the maxillary tissue were made. The changes of periodontal tissues were observed by HE staining and the osteoclast counts were counted. The expression of PGE-2 in periodontal tissues In the expression level. RESULTS: Compared with the control group, the numbers of osteoclasts in three different doses of nicotine group were significantly increased, and with the increase of nicotine dosage, each group compared P <0.05, The number of osteoclasts in each group reached the peak value. Immunohistochemical staining showed that the PGE-2 levels of nicotine intervention group were significantly increased, and with the increase of nicotine dosage, Compared with P <0.05, the expression of PGE-2 in each group reached the peak value at 5 d. CONCLUSION: Nicotine can promote the expression of PGE-2 in periodontal tissues and increase the number of osteoclasts in a dose-dependent manner.