中文摘要：

目的：探讨高脂饮食和Ⅱ型糖尿病对大鼠牙龈组织中二肽基肽酶Ⅳ（DPP—Ⅳ／CD26）表达的影响。方法：将实验动物分为高脂饮食组（HF）、Ⅱ型糖尿病组（DM）和对照组（正常饮食），根据葡萄糖耐量试验异常确定Ⅱ型糖尿病动物模型成功。采用RT—PCR半定量和Western blot测定DPP—Ⅳ／CD26在大鼠肠（回肠）、肝脏、肾脏和牙龈组织中的表达情况。结果 与对照组比较，RT—PCR半定量测定HF组大鼠小肠、肾脏及牙龈组织内DPP—Ⅳ mRNA表达明显增加（151．58％，239．73％，169．7％，P〈0．05），肝脏的DPP—Ⅳ无明显变化；DM组大鼠小肠、肾脏、肝脏和牙龈组织DPP—Ⅳ mRNA表达均明显增加（242．36％，324．93％，190．57％，267．4％，P〈0．01）。Western blot证实HF组大鼠DPP—Ⅳ蛋白表达在小肠、肾脏、牙龈组织内中度增加（152．37％，154．17％，157．8％，P〈0．05），而在肝脏无明显增加；DM组大鼠DPP—Ⅳ蛋白表达在小肠、。肾脏、肝脏和牙龈组织均明显增加（222．5％，210．82％，225．43％，254．7％，P〈0．01）。结论：在高脂饮食和Ⅱ型糖尿病时牙龈组织中DPP—Ⅳ表达上调，而这种上调可能是Ⅱ型糖尿病影响牙周炎发生发展的机制之一。

英文摘要：

AIM： To explore the expression of DPP - Ⅳ in intestine, kidney, liver and gingiva of rat in high fat diet and Type Ⅱ diabetes mellitus . METHODS ： Rats were devided into control, high fat diet （ HF ） and HF plus streptozotocin for type Ⅱ diabetes mellitus （DM） groups. Type Ⅱ diabetes mellitus rats were monitored with plasma glucose and insulin for 12 weeks and confirmed by the glucose/insulin tolerance test. The expressions of DPP - Ⅳ/ CD26 in the intestine, liver, kidney and gingiva in three groups were evaluated in mRNA and protein levels with RT - PCR and Western blotting. RESULTS： Compared to rats on the normal diet , the rats with a high fat diet significantly increased the expressions of DPP -Ⅳ（ mRNA / protein） 151.58% / 152.37% in the intestine; 239.73%/154.17% in the kidney and 169.7%/157.8% in the gingiva （ P 〈 0.05 ） , but there was no chang in the liver. The rats treated with high fat diet plus streptozotocin showed an increase in the expressions of DPP- Ⅳ（mRNA/protein） 242.36%/ 222.5% in intestine; 324.93% / 210.82% in kidney; 190.57% / 225.43% in liver and 267.4%/254.7% in gingiva （ P 〈 0.05 ）. CONCLUSION ： This study reports that an increase in the expressions of DPP - Ⅳ in gingiva is associated with high fat diet and Type Ⅱ diabetes mellitus . The evidence in this study suggests a hypothesis that the upregulation of the expressions of DPP - Ⅳ would contribute to a role in the development of gingivitis.