[Studies on comparing the toxicity between sodium selenite and selenomethionine in rats].
OBJECTIVE
To compare the toxicity between sodium selenite and selenomethionine (SeM) and to investigate the indicators of selenium toxicity.


METHODS
Weanling Wistar rats of both sexes were randomly divided into seven groups, 14 rats each group. One group was fed basal diet and the others were fed basal diets containing 3, 6, 10 mg greater than that of SeM and female rats were more sensitive to excessive selenium than male rats. Se/kg added as sodium selenite or SeM for 12 weeks.


RESULTS
Histopathological changes of the liver were observed in rats on Se 3 mg/kg diets while the decreasing of body weight occurred in rats on 6 Se mg/kg diet. Among the rats fed Se 6, 10 mg/kg diet, the body weight of rats in selenite-treated groups was lower than that of rats in SeM-treated groups. At the 3 or 6 mg/kg Se level, the rats fed SeM suffered slighter hepatic damage than those fed sodium selenite and in male rats slighter than female rats. The abnormal change of ratio of liver weight to body weight was found to be more obvious both in female rats and in selenite-treated rats. GPX activity in liver of female rats reduced with the increase of Se level in diets. However, GPX activity in RBC, plasma, kidneys and liver showed an ascending tendency with the increasing level of dietary Se.


CONCLUSIONS
The minimum dose of intoxication of Se in diet may be around 3 mg/kg. The toxicity of selenite is greater than that of SeM and female rats were more sensitive to excessive selenium than male rats.
Mu
Weipeng
W
Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Tian
Yuan
Y
Piao
Jianhua
J
Gu
Lüzhen
L
Yang
Xiaoguang
X
D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008297:Male; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012645:Selenomethionine / Q000633:toxicity*; D018038:Sodium Selenite / Q000633:toxicity*
D012645:Selenomethionine; D005979:Glutathione Peroxidase; D018038:Sodium Selenite