Collection of rats’ urine and blood : A urinary sample was collected from each rat over 24 hr using metabolic cage on day 0 and day 28 and a blood sample was collected by cardiac puncture on the last day of the experiment after the rats were anesthetized intraperitoneally with sodium phenobarbital solution. After perfusion of the whole animal with physiological saline via the portal vein, the kidneys and livers were removed, washed with physiological saline solution and fixed in 10% neutral-buffered formalin for 48 hr for histopathological examination.