The experiment utilized a total of 54 five-week-old Sprague-Dawley rats, each weighing approximately 100 grams. These rats were randomly divided into 9 groups, consisting of 27 female and 27 male rats. Based on the intervention dose of cadmium (Cd), the rats were further randomly assigned into 3 main groups, each containing 18 rats: the control group received 1 milliliter of sodium chloride solution daily; the low-dose group received 1 milliliter of cadmium chloride (CdCl₂) solution at a concentration of 30 micrograms per kilogram (μg/kg) daily; and the high-dose group received 1 milliliter of cadmium chloride (CdCl₂) solution at a concentration of 1 milligram per kilogram (mg/kg) daily. Cadmium exposure was administered via oral gavage. Each dose group (control group, low-dose group, and high-dose group) was intervened at three different time points: 2 weeks, 4 weeks, and 8 weeks. At each intervention time point, 6 rats were randomly selected from each dose group for euthanasia, and their prefrontal brain tissues were collected for subsequent analysis. During the experiment, some rats died: 2 rats in the control group died at 2 weeks, and 1 rat in the high-dose group died at 4 weeks and 8 weeks, respectively. The experimental design ensured a systematic evaluation of the effects of cadmium exposure on rats under different doses and time points, while recording the mortality during the experiment for further analysis.