Regeneration Potential of Lymphoid Tissue of Small Intestine in Mice after Exposure to Low-Intensity Radiation

Abstract

Number and size of aggregated lymphoid nodules in the small intestine of mice exposed to radiation using a γ-irradiation unit GOBO-60 with ¹³⁷Cs source were measured using the methods of visual microscopy and morphometry. Morphological status of the nodules was estimated on days 4, 28, 60, and 90 after the exposure. Significant changes were observed in the lymphoid system of the small intestine after exposure to low-intensity radiation. The size of aggregated lymphoid nodules decreased and the relative number of cells with degenerative changes increased. Regenerative processes were observed as soon as on day 4 of the rehabilitation period. However, the number and sizes of aggregated lymphoid nodules (length, width, and section area), and the ratio of lymphoid nodules with germinal center were still lower than in the control. The number of cells forming lymphoid interstitial plaques was close to the control on days 28-90 of the rehabilitation process.