Purpose: To study the use of different doses to irradiate the head of rats, select the appropriate dose to establish an animal model of cognitive impairment caused by ionizing radiation, and to study the mechanism of cognitive impairment caused by ionizing radiation.
Methods: Twenty male SPF rats were randomly divided into control group (C group), 10Gy irradiation group (10GyIR group), 20Gy irradiation group (20GyIR group) and 30Gy irradiation group (30GyIR group), and 5 C group still Received treatment, while the other three groups used 10 Gy, 20 Gy and 30 Gy electron beams to irradiate the heads of SD rats in different groups at once. Animal mortality was calculated 30 days after irradiation. The Morris water maze is used to test the spatial memory ability of rats. Using chemical colorimetry can reduce glutathione (GSH) in rat cerebral cortex homogenate? Detection of malondialdehyde (MDA) and enzyme-conjugated immunosorbent assay (enzyme-conjugated immunosorbent assay). Deoxyguanosine (8-hydroxydeoxyguanosine, 8-OHdG) content can detect 8 hydroxyl groups to detect and observe HE-stained pathological sections.
Results: The 30GyIR group had irregular hairs, salivation and other symptoms. Symptoms: 30 days after the photo, there was no animal mortality in the C group. The animal mortality in the 10GyIR and 20GyIR groups was 20%, and the animal mortality was 20%. This is 40% of the 30GyIR group. The results of the Morris water maze positioning and navigation experiment showed that the 30 GyIR group had 1-5 days. During training, the incubation period was longer than the other three groups, and the difference was statistically significant (P\u003c0.05); in the space exploration experiment, the 30 GyIR group was in the original platform quadrant than the other groups. We found that our stay time was obvious Shortened (P\u003c0.05); the number of platform crossings was significantly reduced (P\u003c0.05); 10GyIR group, 20GyIR group, 30GyIR group, the meta-quadrant was significantly shorter than C group (P\u003c0.05). The test results of oxidative stress-related indicators showed that compared with the C group, the 30 GyIR group had a higher GSH-8 content. -OHdG? The difference in MDA concentration is statistically significant (P\u003c0.05), and the difference in MDA concentration between the 20GyIR group and the C group is statistically significant (P\u003c0.05); it is found that the damage is greater than that of the 10 GyIR group, whether there are obvious pathological changes such as Seriously, tissue cell apoptosis? Necrosis?
Conclusion: The results of this experiment show that a single irradiation of 30 Gy on the head can successfully establish an animal model of cognitive impairment in rats?