动物造模 z-bio 2022-05-06 432

　　Objective: To observe the changes in the structure and function of the immune system in naturally aged SD rats, and to explore the possible mechanisms?

　　Methods: Sixty SD rats were reared in SPF environment and 10 animals were comforted at the age of 6-12-18-24 months respectively. Lymphocyte function was determined by lymphocyte transformation test and NK cell killing test; Peripheral blood lymphocyte subsets? CBA method was used to detect serum cytokine levels, colorimetric method to detect serum superoxide dismutase (SOD) and malondialdehyde (MDA)? And the thymus and spleen were histopathologically observed.

　　Results: With the increase of age, the transformation ability of lymphocytes decreased? The number of CD8 positive T cells decreased? The killing ability of spleen cells to NK target cells decreased? The amount of IL-2 in serum decreased, and the content of IL-6 and IL-10 increased. SOD decreased, MDA increased? Thymus organ coefficient decreased? Thymus atrophy, spleen medullary sinus expansion, lymphoid follicle atrophy, extramedullary hematopoiesis increased? Mainly present in the medulla, and positive cells gradually increase from the cortex to the medulla?

　　Conclusion: It is suggested that the aging degeneration of the immune system is related to the accumulation of oxidative damage, which provides an experimental basis for the theory of aging immune damage.