Study on the Cyclic Change of Leptin and Its Receptor Expression during the Estrous Cycle of Rat = 흰쥐의 발정주기동안 난소내 Leptin 및 Leptin 수용체 발현의 주기적 변화에 관한 연구

국문 초록 (Abstract)

비만유전자 산물인 leptin은 비만뿐만 아니라 여성의 생식 생리와 관련이 있는 것으로 보이나, 아직 이러한 leptin이 난소에 직접적으로 작용하는지 정확하게 밝혀지지 않고 있다. 따라서 본 연구에서는 흰쥐 난소에서 leptin과 leptin 수용체의 발현을 면역조직화학방법으로 확인하고 발정주기에 따른 leptin과 leptin 수용체의 발현 양상을 RT-PCR 방법으로 조사하고자 하였다. 면역조직화학적 염색방법 결과 흰쥐 난소내에서 leptin은 협

다국어 초록 (Multilingual Abstract)

Leptin, a product of the obese gene, is associated not only with obesity but also with female reproductive function, but it has not yet been ascertained whether leptin acts directly on the ovary or indirectly via the hypothalamus-pituitary pathway. Therefore, the object of this study was to investigate the expession of leptin and its receptor in the rat ovary by immunohistochemistry and RT-PCR during the estrous cycle. Immunohistochemistry results showed that leptin was stained in the theca cells and in part of granulosa cells in atretic follicles, whereas leptin receptor was localized in the interstitial cells and ova in preantral follicies. In particular, leptin and its receptor in atretic follicles displayed more intensive staining compared to those in normal follicles. During the estrous cycle, the mRNA expression of leptin and its receptor in the ovary was detected by RT-PCR and estradiol, progesterone, and leptin levels in the serum was measured by ELISA. The leptin level in the serum on metestrous phase was significantly higher than that on estrous phase. Similar to leptin level, progesterone level increased on metestrous phase. Leptin mRNA was not detected throughout the estrous cycle, whereas leptin receptor mRNA was expressed on all phases of estrous cycle excepting the diestrous phase. These results suggest that leptin might be directly involved in the regulation of ovarian function in rat.