PARENT SESSION
Reproductive Immunology

-RADIATION INDUCES FOLLICULAR DEGENERATION BY APOPTOSIS AND INFLAMMATION IN MICE OVARY.

Lee, Chang Joo¹, Song, Kang Won ¹, Lee, Kyung Hee¹, Kim, Jin Kyu², Yoon, Yong-Dal¹, ^{1 2}

ABSTRACT- This study was undertaken to evaluate the morphological changes of the ovarian follicles in prepubertal mice irradiated by a half lethal dose (LD50) of -radiation. At day 0 before, and day 1, 2, and 3 after the -irradiation, left ovaries were collected and fixed in glutaraldehyde for the histological and electron microscopical observations. The ratios (%) of atretic or polymorphonuclear leukocytes (neutrophil)-containing follicles in the largest cross sections were calculated. In the early atretic follicle of the control mice ovary, both apoptotic and mitotic cells were observed and, occasionally, neutrophils were infiltrated into the follicle cavity. In the severely atretic follicles 2 days post-irradiation, numerous cell fragments, apoptotic cells and bodies, and, especially, neutrophils were observed. In the non-irradiated control, the atretic ratios were 58.0±8.6 and 27.3±11.2 (mean±SEM, n=5) in antral and preantral follicles, respectively. The ratios of the number of antral and preantral follicles with one or more neutrophils to the total number of atretic follicles were 29.3±12.0 (p<0.05). At 2 days post-irradiation, the atretic ratios were increased to 94.0±3.4 and 86.9±7.6 in antral and preantral follicles, respectively. The ratios of neutrophil-containing follicle among the atretic one were increased to 65.9±11.5 and 57.8±15.4 at 2 and 3 days after the irradiation, respectively (p<0.05). Taken together, the present results show that LD50 of -radiation induce the apoptotic and inflammatory degeneration of mouse ovarian follicles. Besides, neutrophils may be involved in the acute atretic degeneration in -irradiated mouse ovarian follicles.

KEY WORDS: ovarian follicle, apoptosis, radiation, neutrophil, mouse