[Intervention of selenium on injured type 1 deiodinase by excessive iodine in mice].

OBJECTIVE:To study the mechanism of the damage resulted from iodine excess and to seek suitable selenium intervention dosage. METHOD:160 BALB/c mice were divided into eight groups, the normal control group, the excessive iodine group (drunk the water containing potassium iodate 3000 microg/L) and six selenium groups (drunk the water containing potassium iodate 3000 microg/L and selenium 0.1, 0.2, 0.3, 0.4, 0.5 and 0.75 mg/L). The type 1 deiodinase (D1) activities and the levels of mRNA in liver, kidney and thyroid were determined by RT-PCR. RESULTS:The mRNA levels of D1 restored to normal levels in all of the IS groups, while only 0.1-0.4 mg/L selenium supplement groups had normal activities of D1 in liver, kidney and thyroid. CONCLUSION:Decline of D1 activities in liver, kidney and thyroid seems to be one of the reasons of the damage and should be chosen for effective intervention.