Immunohistochemical study on the atretic and the growing follicles after experimental superovulation in rats 2. Atresia and growing of follicles

Kwak, Soo-dong; Koh, Phil-ok; Kim, Chong-sup

Korean Journal of Veterinary Research 1997;37(1):79-86.

Soo-dong Kwak, Phil-ok Koh, Chong-sup Kim

Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University

과배란 유기된 rat 난소에 퇴축난포와 성장난포에 대한 면역조직화학적 연구 2. 동원된 난포의 퇴축과 성장에 대하여

곽수동, 고필옥, 김종섭

경상대학교 수의과대학 동물의학연구소

Abstract

This study was designed to investigate the effects of superovulation on the growing and mature follicles following gonadotrophin treatments in mature rat by immunohistochemical methods. Eighteen mature rats (Sprague-Duwely, 190~230gm) were randomly alloted into 3 groups. One group was control group, another FSH-treated group was injected intramuscularly with 0.5 units of follicular stimulating hormone(FSH) / rat, and third PMS and HCG-treated group was injected intramuscularly with 20~25IU of pregnant mare serum(PMS) / rat and then at the 48 hrs later, with 20~25IU of human chorionic gonadotropin(HCG) / rat. Half the number of rats were administrated intraperitoneally with bromodeoxyuridine(Brdur, 0.2mg/gm BW once) at 2 hours before exanguination and the remainder of rats were sacrified without Brdur administration. The investigation by immunohistochemical methods using paraffin sections of ovaries was performed by using anti-Brdur antibody and PCNA(proliferating cell nuclear antigen) antibody for labeling proliferating cells in follicles. In immunohistochemical findings, follicles squeezed by peripheral corpus luteum or follicles large follicles with loosly and irregularly distributed granulosa cells and although with compacted granulosa cells, middle follicles with dilated round or oval follicular antrum were confirmed as atretic follicles. The proportions of atretic follicles in control group were 29.8%, 21.7% and 14.2% respectivley at large, middle and small follicles and mean proportions of these all 3 grade follicles were 26.7%. The proportions of atretic follicles in FSH-treated group were 35.4%, 24.9% and 10.4% respectively at large, middle and small follicles and mean proportions of these all 3 grade follicles were 28.1%. The proportions of atretic follicles in PMS and HCG-treated group were 44.7%, 24.0% and 12.7% respectively at large, middle and small follicles, and mean proportions of these all 3 grade follicles were 29.7%. The above findings reveal that the group with higher proportion of atretic follicles were ordered as large, middle and small follicles in size, and these proportions were increased in hormone treated two groups with more number of more growing and mature follicles when compared with control group.

Key Words: superovulation, atretic follicles, ovary, rat, immunohistochemistry