ObjectiveTo compare the intervention mechanism of Ha izao Yuhu Decoctio n（Sargassum Jade Flask Decoction） and its decomposed recipes for goiter caused by iodine deficiency from anti-oxidative stress.MethodsTotally 150 4-week-old Wistar rats were selected.Thirty randomly-selected rats were taken into normal control group

and others were used to make the models of goiter caused by iodine de ficiency

the rats were devided into model control（MC） group

Haizao Yuhu Decoction group（HZ group）

Haizao Yuhu Decoction decomposed recipe group A（HZA group） and Haizao Yuhu Decoction decomposed recipe group B（HZB group） with 30 in each group.The rats were killed after modeling and 8 weeks later respectively.The median of urinary iod ine（MUI）

thyroid stimulating hormone（TSH）

total triiodothyronine（TT3） and t otal thyroxine（TT4） was measured.The quantitative observation of thyroid morph ology was conducted under optical microscope and the ultrastructure of thyroid c ells was observed under electron microscopy.The contents of serum glutathione p eroxidase（GSH-Px）

xanthineoxidase（XOD）

superoxide dismutase（SOD）

malondia l dehyde（MDA） and hydrogen peroxide（H2O2） were detected.The expression of 4-hy d roxynonenal（4-HNE） in the thyroid was detected by the immunohistochemistry met h od.The expression of peroxide oxidation reduction enzyme5（PRDX5） in the th yroi d was detected by the Western blotting and immunohistochemistry method. ResultsAfter 8 weeks of treatment

MUI was decreased in the MC group and HZA group

while MUI was increased in the HZ group and HZB group.TSH value was significantly decreased in the three treated groups as compared with the MC group（P

<

0.05）.TT3 value in the HZ group was obviously decreased as compared with the NC group（P

<

0.01）.TT3 value in the HZA group was obviously increased as compared with the MC gr oup and HZ group（P

<

0.05）.TT4 value in the HZ group and HZB group was signifi cantly higher than that in the NC group and MC group（P

<

0.05 or P

<

0.01）.TT4 value in the HZA group was significantly lower than that in the HZ group（P

<

0.05）.The relative thyroid weight in the HZ group and HZB group was significantly lo wer than that in the MC group（P

<

0.01）.The relative thyroid weight in the HZA group was significantly higher than that in the NC group（P

<

0.05）.The activity of SOD in the HZ group increased significantly as compared with the N C group and HZB group（P

<

0.05）.The activity of GSH-Px in the HZ group and HZA group increased significantly as compared with the HZB group（P

<

0.05）.The content of H

2

O

2

in the HZ group increased significantly as compared with the NC group（P

<

0.05）.The content of MDA in the HZA group was significantly higher th an that in the NC group（P

<

0.05）.The activity of XOD increased significantly in all the treatment groups as compared with the NC group and the MC group（P

<

0.01）

espe cially in the HZA group

significantly different as compared with the HZ group and HZB group（P

<

0.01）.The expression of 4-HNE in the HZ group was significantly lower than that in other groups（P

<

0.05）.The expression of PRDX5 in the HZ group was increased significantly as compared with the NC group （P

<

0.01）.ConclusionHaizao Yuhu Decoction has bet ter antioxidation effect than its decomposed recipes.It could make goiter recovery completely without the damage of thyroid cell.