The present study was performed to identify changes of plasminogen activator (PA) and plasminogen activator inhibitor (PAI) in porcine oviduct epithelial cells (POECs) during the estrous cycle. POECs obtained from ovary in pre‐ovulatory (Pre‐Ov), early to mid‐luteal stage (Early‐mid L) and post‐ovulatory stage (Post‐Ov). For the examine of PA activity, 1×105 fresh cells of POECs were cultured in DMEM/Ham F‐12 containing 10% FBS and 0.2% amphotericin under humidified atmosphere of 5% CO2 in air and 38℃. The urokinase‐type PA (uPA) was observed at 7 days of POECs culture. PA activity was measured with culture prolonged of 0, 3, 6, 12 and 24 hafter culture of 7 days. The PA activity were high significantly (p<0.05) at 12 h of culture, but PA activity were decreased with culture periods increased. The PA activity in POECs of Post‐Ov stage were higher significantly (p<0.05) than that of Early‐mid L and Pre‐Ov stage. When PAI‐1 and PAI‐2 were added during the POECs culture, the PA were observed significant low activity (p<0.05). The PA activity and protein expression were decreased by PA inhibitor. This results suggest that PAI‐1 and PAI‐2 have a suppressive action on change of PA activity uring the estrous cycle of pigs. Specifically, this study using PA inhibitor was effect the PA activity and PAI expression in oviduct epithelial cells in pigs.

This study was conducted to investigate the effect of periods of sperm preincubation, concentrations and storage periods of miniature pig sperm on in vitro penetration of porcine follicular oocytes. High concentration (1×105, 2.5×105, 5×105, 1×106, 5×106 and 1×107) did support sperm penetration than low concentrations (P<0.05). However, polyspermic oocyte rates were increased with high concentrations of sperm. On the other hand, sperm preincubated during 1, 2 or 5h could be penetrated than sperm preincubated during 0, 3 or 4h (P<0.05). When sperm were storaged with different periods, in vitro pentration rates were significantly higher 0～2 days than 3～4 days of sperm storage (p<0.05). These results indicate that sperm treatment factors can effect in vitro penetration in miniature pig.