中文摘要：

目的 观察哺乳期大鼠甲状腺组织促甲状腺激素受体（TSHR）蛋白和mRNA表达.方法 选择成年Wistar大鼠80只,其中雌性60只,雄性20只,体质量为210～ 250 g.按体质量,采用随机数字表法将雌性大鼠分为6组：正常未孕组、哺乳第5、10、15、20天组和断乳第5天组,每组10只.常规饲料喂养,自由饮用自来水.将除正常未孕组外的其他5组雌鼠与雄鼠按3∶1合笼交配,分别在哺乳第5、10、15、20天和断乳第5天时股动脉取血处死动物,取甲状腺组织,采用免疫组织化学实验和实时荧光定量PCR法检测TSHR蛋白和mRNA表达.结果 光镜下,TSHR蛋白表达于大鼠甲状腺滤泡细胞胞质及胞膜上.各组大鼠甲状腺TSHR蛋白表达水平比较,差异有统计学意义（x2=11.227,P＜0.05）.其中,哺乳第5天组（弱阳性7例、中阳性3例）与正常未孕组（弱阳性2例、中阳性5例、强阳性3例）比较,差异有统计学意义（x2=5.895,P＜0.05）;其余各组与正常未孕组比较,差异均无统计学意义（P均＞ 0.05）.各组大鼠甲状腺TSHR mRNA表达水平比较,差异有统计学意义（F=2.970,P＜0.05）.其中哺乳第5天组（0.74±0.13）较正常未孕组（1.02±0.24）明显降低（P＜0.05）;其余各组与正常未孕组比较,差异均无统计学意义（P均＞0.05）.结论 TSHR广泛表达于哺乳期大鼠甲状腺组织中,但哺乳早期甲状腺TSHR表达水平较低.

英文摘要：

Objective To observe the expressions of thyroid-stimulating hormone receptor （TSHR） protein and mRNA in thyroid gland of lactating rats.Methods Eighty adult Wistar rats （60 females and 20 males）,weighting 210-250 g were selected.The 60 female Wistar rats were divided into 6 groups according to their body weight by means of random number table：normal non-pregnant group,lactating for 5,10,15 and 20 days groups and weaning for 5 days group,10 rats in each group.All rats were fed with conventional fodder and tap water freely,and the rats of lactating groups except the normal non-pregnant group cohabited with male rats （3 ∶ 1）.Then all rats were killed on the 5th,10th,15th and 20th day after lactation and on the 5th day after weaning to get thyroid tissues.The expressions of TSHR protein and mRNA were determined by immunohistochemical staining and realtime quantitative PCR.Results TSHR protein was expressed in cytoplasm and membrane of rat thyroid follicular cells.The expression of TSHR protein in thyroid gland was significant different statistically between groups （x2 =11.227,P ＜ 0.05）; the staining intensity of rat thyroid tissues in the normal non-pregnant gruop （weak,n =2; moderate,n =5; strong,n =3） was stronger than that of rats lactating for 5 days （weak,n =7; moderate,n =3; x2 =5.895,P ＜ 0.05）.But the expression of TSHR protein in thyroid tissues in the normal non-pregnant group was not significantly different statistically compared with the expression of TSHR protein in other groups （lactating for 10,15and 20 days） and weaning for 5 days group （all P ＞ 0.05）.The expression of TSHR mRNA in thyroid gland was significantly different statistically between groups （F =2.970,P ＜ 0.05）; the expression of TSHR mRNA in lactating for 5 days group （0.74 ± 0.13） was lower than that of the non-pregnant group （1.02 ± 0.24,P ＜ 0.05）; and the expression of TSHR mRNA in the normal non-pregnant group was not significantly different statistically compared with those of