Differential Expression and Regulation of Angiopoietin-1 in Mouse Ovary during Sexual Maturation and Luteal Development

Angiogenesis, the development of new blood vessels from preexistent vasculature, is recognized to play important roles during follicular development and atresia, ovulation, and the subsequent development and regression of corpus luteum. However, as an important angiogenic factor, the effect of Angiopoietin-1 (Ang-1) in the process of mouse ovary angiogenesis is still not defined in detail so far. The aim of this study was to examine the expression and regulation of Ang-1 in mouse ovary during sexual maturation, follicular development induced by eCG, ovulation induced by hCG and corpus luteum formation and regression by reverse transcription polymerase chain reaction (RT-PCR). The results showed that Ang-1 mRNA expression level was lower on days 10 and 20 after birth, but it was sharply increased on day 25 after birth, while generally decreased. Ang-1 mRNA expression reached the peak level at 48 hours after injection of eCG. At 3, 5 and 9 hours after injection of hCG, Ang-1 mRNA expression decreased, while at 0.5 and 7 hours after injection of hCG, Ang-1 mRNA expression level was higher. Ang-1 mRNA was expressed on days 1-15 after injection of hCG, and Ang-1 expression increased gradually on days 5-15 after injection of hCG, while Ang-1 expression level reached maximum on day 15 after injection of hCG. These results suggest that Ang-1 may play a role during the process of mouse follicular development, ovulation and corpus luteum formation and regression.