The major focus of this study is to analyze the expression of bovine MMPs and to monitor their activity during the estrus cycle and pregnancy. During pregnancy, MMP-2 expression was detectable around 30 days but became insignificant by 60 days, then started to increase again around 90 days and reached the maximum at 250 days. The activity of MMP-2 protein changed in accordance with its expression level. As expected, the level of TIMP-2 exhibited a reverse pattern. About MMP-9, high level expression was observed as early as 30 days and gradually increase until 90 days. Then started to decrease after 250 days. Again, the sites of MMP-9 expression were similar to those of MMP-2. On the other hand, expression of TIMP-3 remained low until 90 days but showed a small and temporal increase around 250 days. In summary, expression of different MMPs were differentially regulated during estrus cycle and pregnancy. While the expression of MMP-2 was high in estrus cycle, MMP-9 slowly takes over with the progression of pregnancy. These results indicated that the luteal tissue perform distinct functions during pregnancy and estrus. Perhaps the activity of MMP-2 is required for the structural remodeling of luteum, resulting the suppression of P4 inflow from blood. On the other hand, steady maintenance of MMP-9 throughout luteal development is important for the activation of cell proliferation, maturation and angiogenesis.

The aim of this study was to evaluate the changes of protein patterns in granulosa cells and corpus luteum during the estrus cycle in bovine ovary by proteomics ^techniques. Our study was devided into five steps for follicular, ovulatory, early-lteal, midluteal and late-luteal. The protein was extracted from glanulosa cell and corpus luteum proteins by using M-PER Mammalian Protein Extraction Reagent. Proteins were refined by clean-up kit and quantified by Bradford method until total protein was 700 μg. Immobilized pH gradient (IPG) strip was used 18 cm and 3 11 NL. SDS-PAGE was used 10% acrylamide gel. The protein spots were visualized by Coomassie Brilliant Blue (CBB) staining, analyzed by MALDI mass spectrometry and searched on NCIBlnr. As the result, 61 spots of total 85 spots were repeated on follicular stage and 51 spots of total 114 spots were repeated on ovulatory stage. 40 spots of total 129 were repeated on early-luteal and 49 spots of total 104 spots were repeated on mid-luteal stage. Also 41 spots of total 60 spots were repeated on last-luteal stage. There were differences in the ovulation (follicular∼ovultory stage) in which the spots of follicular stage 19 was only and in ovulation stage was 10 spots. The difference between the luteinization (ovultory∼mid-luteal stage) was the spots counted in each stage. The spots of ovulatory stage was 1, early-luteal stage was 1 and in mid-luteal stage was 2. Eleven spots were found in mid-luteal stage and 2 spots were found in last-luteal stage. In conclusion, we confirmed that there were 7 spots in ovulation, 4 spots in luteinization and 2 spots in luteolysis. Spot No. 89-93 from ovulation were transferrin, and spot No.94 and 95 were HSP60. Spot No. 103 were Dusty PK, spot No. 135 were OGDC-E2, and spot No. 175, 176 were Rab GDI beta from luteinization. Spot No. 178 and 179 from luteolysis were vimentin.