TSH-THSR-cAMP-PKA信号通路在哺乳期大鼠乳腺摄碘过程中的作用  

The role of TSH-THSR-cAMP-PKA signal pathway in the process of iodine uptake in lactating rat mammary gland

作　　者：薛靓 文达 史新竹 金星 王丹丹 刘丽香 申红梅 Xue Liang;Wen Da;Shi Xinzhu;Jin Xing;Wang Dandan;Liu Lixiang;Shen Hongmei(Institute for Iodine Deficiency Disorders Control,Center for Endemic Disease Control,Chinese Center for Disease Control and Prevention,Key Laboratory of Etiology and Epidemiology,National Health Commission&Education Bureau of Heilongjiang Province,Harbin Medical University,Harbin 150081,China)

机构地区：[1]哈尔滨医科大学中国疾病预防控制中心地方病控制中心碘缺乏病防治研究所国家卫生健康委病因流行病学重点实验室黑龙江省普通高校病因流行病学重点实验室,哈尔滨150081

出　　处：《中华地方病学杂志》2022年第7期532-539,共8页Chinese Journal of Endemiology

基　　金：国家自然科学基金(81273012)。

摘　　要：目的:观察不同碘营养水平哺乳期大鼠乳腺组织促甲状腺激素受体(TSHR)、蛋白激酶A(PKA)、钠碘转运体(NIS)mRNA和蛋白的表达,探讨促甲状腺激素(TSH)-THSR-环磷酸腺苷(cAMP)-PKA信号通路在哺乳期乳腺摄碘过程中的作用。方法:采用成组设计,按体质量(80~100 g)采用随机数字表法将110只雌性Wistar大鼠分为适碘(NI)组、重度低碘(SID)组、中度低碘(MID)组、中度高碘(MIE)组、重度高碘(SIE)组,每组22只。另选取22只雄性Wistar大鼠,喂养情况与NI组一致。饲养3个月时,收集雌鼠24 h尿样,并将雌鼠与雄鼠合笼(5∶1),交配后,每只雌鼠单独喂养,在生育10 d时,处死哺乳期大鼠取甲状腺、乳腺组织。采用砷铈催化分光光度法测定尿碘;HE染色观察甲状腺和乳腺组织形态学改变;实时荧光定量PCR(real-time PCR)法检测甲状腺和乳腺组织TSHR、PKA及NIS mRNA表达水平;蛋白免疫印迹法(Western blot)检测乳腺组织TSHR、PKA、磷酸化PKA(p-PKA)及NIS蛋白表达水平。结果:与NI组比较(162.59μg/L),SID、MID组雌鼠尿碘中位数(3.16、6.36μg/L)均较低,MIE、SIE组雌鼠尿碘中位数(2356.27、11507.29μg/L)均较高(P均<0.01)。HE染色可见,不同摄碘水平对甲状腺滤泡产生不同的影响:NI组多为均匀的圆形或椭圆形滤泡;MID组小滤泡增多,上皮细胞呈单层柱状或立方,滤泡腔变小,胶质减少;SID组滤泡变小,上皮细胞呈柱状或高柱状,滤泡腔内胶质减少或缺如;SIE、MIE组甲状腺滤泡出现多形性变化,既有部分滤泡明显增大,又有部分小滤泡增生。不同摄碘水平对乳腺大导管也产生不同的影响:与NI组相比,SID、MID组乳腺大导管周围的结缔组织呈明显的纤维化,而MIE、SIE组纤维化明显减轻。real-time PCR结果显示,不同碘营养水平哺乳期大鼠甲状腺组织TSHR、PKA、NIS mRNA表达水平比较,差异均有统计学意义(F=10.73、92.37、115.75,P均<0.01);乳腺组织TSHR、PKA、NIS mRNA表达水平�Objective To observe the mRNA and protein expression levels of thyroid stimulating hormone receptor(TSHR),protein kinase A(PKA)and sodium iodine transporter(NIS)in mammary gland tissue of lactating rats with different iodine nutrition levels,and to explore the role of thyroid stimulating hormone(TSH)-THSR-cyclic adenosine monophosphate(cAMP)-PKA signal pathway in the process of mammary iodine uptake during lactation.Methods Using a group design,according to body weight(80-100 g),110 Wistar female rats were randomly divided into normal iodine(NI)group,severe iodine deficiency(SID)group,moderately iodine deficiency(MID)group,moderately iodine excess(MIE)group and severe iodine excess(SIE)group,with 22 rats in each group.Another 22 Wistar male rats were selected,and the feeding situation was consistent with that of NI group.After 3 months of feeding,24-hour urine samples of female rats were collected,and the female rats were caged with the male rats(5∶1).After mating,each female rat was fed separately.At 10 days of childbirth,the lactating rats were sacrificed and thyroid and mammary gland tissues were taken.The urinary iodine was determined by arsenic cerium catalytic spectrophotometry.The morphological changes of thyroid and mammary gland tissues were observed by HE staining.The mRNA expression levels of TSHR,PKA and NIS in thyroid and mammary gland tissues were measured by real-time PCR;the protein expression levels of TSHR,PKA,phosphorylated PKA(p-PKA),and NIS in mammary gland tissue were measured by Western blotting.Results Compared with NI group(162.59μg/L),the median urinary iodine of female rats in SID and MID groups(3.16,6.36μg/L)was lower,and the median urinary iodine of female rats in MIE and SIE groups(2356.27,11507.29μg/L)was higher(P<0.01).HE staining showed that different levels of iodine uptake had different effects on thyroid follicles:most of the follicles in NI group were uniform round or oval;in MID group,the number of small follicles increased,the epithelial cells were monolayer columnar or

关 键 词：碘 促甲状腺激素受体 蛋白激酶A 钠碘转运体 大鼠 哺乳期 乳腺 信号通路 

分 类 号：R153.1[医药卫生—营养与食品卫生学]