Effect of excessive iodine intake on sodium-iodide symporter mRNA and protein expression of breast in lactating rats
- VernacularTitle:碘过量对哺乳期母鼠乳腺钠碘转运体mRNA和蛋白表达的影响
- Author:
Lai-xiang, LIN
;
Yi-na, SUN
;
Yan, YE
;
Jin-ru, DONG
;
Rui, YAN
;
Yu-qing, YAN
;
Zu-pei, CHEN
- Publication Type:Journal Article
- Keywords:
Iodine;
Mammary glands.animal;
Sodium-iodide symporter
- From:Chinese Journal of Endemiology
2008;27(3):247-250
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study effect of excessive iodine intake on sodium-iodide symporter(NIS)mRNA and protein expression of breast in lactating rats.Methods60 Wistar rats,having been weaned for one month,were randomly divided into three groups according to their body weights,I.e,①normal iodine(NI,30 rats);②ten fold high iodine(10 HI,15 rats);③one hundred fold high iodine(100 HI,15 rats).Eating food containing iodine of 300μg/L and drinking water of iodine at 5,1845,20 295μg/L,respectively.After fed for 3 months,the rats mated and had offspring,and urine and milk iodine of lactating rats were determined by As-Ce-catalytic spectrophotometric method.Their marmnary glands were sampled at lactation day 10.Then NIS mRNA expression by RT-PCR was determined and NIS protein by immunohistochemistry(SABC)was observed.Results The urine iodine of 10 HI group(3597.5μg/L)and 100HI group(25 404.3μg/L)increased obviously compared with that of NI group(344.7μg/L).The milk iodine of 10HI group(27.1×103μg/L)and 100HI group(191.0×1μg/L)was higher than that of NI group(6.0×103μg/L),but the increased fold of milk iodine was not paralleled with that of urine iodine.Difference of NIS mRNA expression was significant(F=24.19,P<0.01)among the groups,and the NIS mRNA expression in 10HI(1.250±0.034)and 100HI(1.272±0.039)group were less than that in NI (1.532±0.044)group(P<0.01).The breast NIS mRNA expression in lactating rats(1.532±0.044)was significantly higher than that in unlactating rats(0.879±0.018,P<0.01).With the increasing iodine uptake,NIS protein expression decreased.Conclusions The NIS mRNA and protein in rat breasts is down-regulated by excessive iodine intake.So increasing extent of milk iodine concentration is inhibited,which is important to prevent off-spring from getting excessive iodine intake from parental generation.