| ICR rat water |
Subchronic (30-90 days) |
After one week initial adjustment period, rats were randomly divided into four groups based on body weight and each group had five males and five females. Chronic fluorosis process was established by adding sodium fluoride into distilled water at different concentrations. Low fluoride exposure group was treated by drinking water containing NaF at a level of 5 mg/kg body weight; medium fluoride exposure group was treated by drinking water containing NaF at a level of 10 mg/kg body weight; high fluoride exposure group was treated by drinking water containing NaF at a level of 20 mg/kg body weight; and the control group was treated by drinking distilled water only. Rats were fed with standard animal food during the test period and the room temperature was maintained between 18 to 22°C. The water (with and without NaF) was prepared on a daily basis. The body weight of rats were measured every week with empty stomach, which values were used to adjust dosing levels. The exposure period lasted 90 days.; Forty clean SD rats, whose weights were between 80 and 120g and with a 1:1 female to male ratio, were provided by the Laboratory Animal Center of Xinjiang Medical University. Tested animals could drink and eat food freely. |