AFMK对大鼠牙本质生长的影响

Effects of AFMK on dentine development in rats

目的观察N1-乙酰基-N2-甲酰基-5-甲氧基犬尿氨酸(AFMK)对新生SD大鼠牙本质生长的影响。方法选取出生后1d的SD乳鼠10只,随机分为AFMK组和对照组,AFMK组于出生第4,5,6,7天腹腔注射AFMK(10mg/kg),对照组腹腔注射相同剂量的生理盐水。各组新生鼠均于出生第2,6,10天腹腔注射盐酸四环素(25mg/kg),出生第4,8天腹腔注射钙黄绿素(10mg/kg),第16天取大鼠下颌切牙,10%甲酸部分脱钙制作冰冻切片,荧光显微镜下观察牙本质荧光标记线,测量相邻两荧光标记线之间的距离(荧光线间距)。结果AFMK组新生鼠出生后第4天~第6天和第6天~第8天牙本质生长量明显少于对照组(P<0.05),第2天~第4天和第8天~第10天与对照组生长量比较,差异无统计学意义(P>0.05)。AFMK组新生鼠总的牙本质生长量明显少于对照组(P<0.05),并且总牙本质生长量唇侧明显大于舌侧(P<0.05)。结论AFMK可抑制SD乳鼠早期牙本质的生长。

Objective To determine whether N1-acetyl-N2-formyl-5-methoxykynu-ramine(AFMK)affects the dentine formation of SD rats.Methods Ten 1-day-postnatal SD rat were randomly divided into AFMK group and controls.The AFMK group rats were received an AFMK intraperitoneal injection(10mg/kg,BW,i.p.)once a day on day 4,5,6 and 7,while the control group rats were injected with physiological saline.To detect the incremental line of dentine of mandibular incisor,all rats were received tetracycline injections(25mg/kg,BW,i.p.)on day 2,6 and 10,and calcein were injected(10mg/kg,BW,i.p.)on day 4 and 8.On day 16,the mandibular incisors were excised.Then the sections were observed by fluorescence microscope.The width between the fluorescence-labeled line were measured.Results For neonatal SD rat,the newly formed dentine of AFMK-treated rats was significantly less than the control group on day 4 to 6 and day 6 to 8(P<0.05),but on day 2 to 4 and day 8 to 10,there were no significant difference between them(P>0.05).However,total new dentine formation after AFMK treatments were still less than the control group(P<0.05),and total new dentine formation of the labial were more than the lingual(P<0.05).Conclusion AFMK inhibited the dentine development of rats at early stage.