摘要目的 探讨孕期和哺乳期大鼠甲状腺球蛋白(Tg)和甲状腺过氧化物酶(TPO)mRNA及蛋白的表达变化.方法 选择SPF/VAF级成年Wistar大鼠96只,其中雌性84只,雄性12只,体质量为220 ～ 260 g.将雌性大鼠按体质量采用随机数字表法分为7组:对照组,孕早、中、晚期组(7、14、21 d)和哺乳早、中、晚期组(7、14、21 d),每组12只.常规饲料喂养,自由饮用去离子水.除对照组外,将其他6组雌鼠与雄性大鼠按1∶1合笼交配,分别于孕期和哺乳期7、14、21 d分离甲状腺组织,采用实时荧光定量PCR(qRT-PCR)和蛋白免疫印迹法(Western Blot)检测Tg、TPO的mRNA和蛋白表达.结果 对照组,孕早、中、晚期组和哺乳早、中、晚期组大鼠甲状腺组织的Tg mRNA表达(1.05±0.01、3.20±0.23、1.88±0.12、2.69±0.20、1.53±0.19、2.37±0.31、2.23±0.12)组间比较差异有统计学意义(F=42.864,P＜0.05),孕期和哺乳期各组均高于对照组(P均＜0.05);Tg蛋白的表达(0.15±0.01、0.38±0.01、0.32±0.02、0.37±0.01、0.21±0.01、0.35±0.01、0.44±0.01)组间比较差异有统计学意义(F=232.250,P＜ 0.05),且孕期和哺乳期各组均高于对照组(P均＜0.05).对照组,孕早、中、晚期组和哺乳早、中、晚期组大鼠甲状腺组织的TPO mRNA的表达(0.57±0.01、0.74±0.03、0.78±0.13、1.08±0.10、0.98±0.10、1.00±0.07、0.76±0.05)组间比较差异有统计学意义(F=15.448,P＜0.05),孕期和哺乳期各组与对照组比较差异有统计学意义(P均＜ 0.05);TPO蛋白在对照组,孕早、中、晚期组和哺乳早、中、晚期组的表达(0.23±0.01、0.41±0.01、0.72±0.02、0.78±0.01、0.49±0.01、0.52±0.01、0.45±0.02)组间比较差异有统计学意义(F=563.692,P＜ 0.05),且孕期和哺乳期各组与对照组比较差异均有统计学意义(P均＜0.05).结论 孕期和哺乳期大鼠甲状腺Tg、TPO mRNA及蛋白表达上升,可能与大鼠甲状腺激素相对不足,甲状腺功能呈现轻度低下有关.

abstractsObjective To observe the mRNA and protein expression of thyroglobulin (Tg) and thyroid peroxidase (TPO) in each trimester of pregnant and lactating Wistar rats.Methods Ninety-six SPFNAF Wistar rats (84 female and 12 male),weighting 220-260 g were involved.All female Wistar rats were randomly divided into 7 groups according to their body mass via the random number table method:control group,early pregnancy group (7 d),midpregnancy group (14 d),late pregnancy group (21 d),early lactation group (7 d),midlactation group (14 d) and late lactation group (21 d),12 rats in each group.The rats were fed with conventional feed and drank deionized water freely.Female rats of the last 6 groups were mated with male rats.Thyroids were collected on the 7 d,14 d and 21 d of their pregnancy and lactation,respectively.The mRNA expression levels of Tg and TPO were detected by quantitative real-time PCR,and the protein expression levels of Tg and TPO were detected by Western blotting.Results The expression levels of Tg mRNA in thyroid tissue in the control group,early,middle and late pregnancy and early,middle and late lactation (1.05 ± 0.01,3.20 ± 0.23,1.88 ± 0.12,2.69 ± 0.20,1.53 ± 0.19,2.37 ± 0.31,2.23 ± 0.12) were significantly different between groups (F =42.864,P ＜ 0.05),and those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression levels of Tg protein were 0.15 ± 0.01,0.38 ± 0.01,0.32 ± 0.02,0.37 ± 0.01,0.21 ± 0.01,0.35 ± 0.01,0.44 ± 0.01,respectively.The differences between groups were statistically significant (F =232.250,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression levels of TPO mRNA in thyroid tissue in the control group,early,middle and late pregnancy and early,middle and late lactation (0.57 ± 0.01,0.74 ± 0.03,0.78 ± 0.13,1.08 ± 0.10,0.98 ± 0.10,1.00 ± 0.07,0.76 ± 0.05) were significantly different between groups (F =15.448,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression of TPO protein were 0.23 ± 0.01,0.41 ± 0.01,0.72 ± 0.02,0.78 ± 0.01,0.49 ± 0.01,0.52 ± 0.01,0.45 ± 0.02,respectively.The differences between groups were statistically significant (F =563.692,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).Conclusions The mRNA and protein expression levels of TPO and Tg have increased in pregnant and lactating rats.This performance may be raleted to thyroid hormone deficiency and mild hypothyroidism.