Objective: To observe histopathologic changes of irradiated guinea pigs' nasal mucosa treated with intranasal corticosteroids and to study the radioprotective effect of intranasal corticosteroids.
Method: Fifty health guinea pigs nasal parts were performed irradiation by the WDVE-6MeV linear accelerator. They had accepted 5 Gy one time per week for three weeks through X-ray irradiating to establish the animal irradiation injury model. After that, they were divided into 2 groups randomly: the control group and the administration group and each group had 25 guinea pigs. The administration group received intranasal corticosteroids on the second day after three weeks irradiation, 5 animals per one group were sacrificed randomly at 1 W, 1 M, 2 M, 3 M, 4 M after administration, the histopathologic changes were observed under optical, scanning electron and transmission electron microscope respectively.
Result: Using intranasal corticosteroids after irradiation, the early inflammatory reaction of the administration group was milder than the control group. With the drug being given constantly, the recovery of epithelial cell with irradiated damage was accelerated and the coverage rate of cilia went up obviously; After four months, the coverage rate of cilia had risen to 72.9%; But, for the control group, the coverage rate of cilia is only 50.2%. The atrophy of submucosal glandular organ was lessened and they displayed some extent secretory function. The reparation was accelerated as time went by.
Conclusion: Irradiation brought about serious injury on guinea pigs' nasal mucosa. But, the injury was lessen after using intranasal corticosteroids. Intranasal corticosteroids play the role of radioprotection for the irradiated nasal mucosa.