title: Increased expression and localization of a serine protease inhibitor, protease nexin-1 (PN-1), in the ovary and uterus during implantation in rat.
abstract: Protease nexin-1 (PN-1) is a serine protease inhibitor (serpin) that inactivates several proteases, including thrombin, urokinase, plasminogen activators (PA), and plasmin. It also plays a role in regulating proteolytic activity generated by PA system. PN-1 is known to be involved in tissue remodeling, cellular invasiveness, matrix degradation, and tumor growth. However, the role of PN-1 in female reproductive tracts, such as the uterus, ovary, and oviduct, during pregnancy is not known. The present study was designed to investigate the changes of PN-1 mRNA level and localization in the tracts during implantation and early pregnancy by using reverse transcription (RT)-polymerase chain reaction (PCR) and in situ hybridization. We found that PN-1 mRNA levels were coordinately regulated during early pregnancy in a stage- and tissue-specific manner, such that an increased expression of PN-1 gene appeared at the time of the implantation period in the uterus and ovary. Both the uterus and ovary synthesized PN-1 mRNA and their maximal PN-1 expression occurred on Day 6.5 postcoitum (p.c.). On 13.5 days of pregnancy, PN-1 level was low in the uterus and ovary. On the other hand, PN-1 mRNA in the oviduct did not show after 6.5 days of pregnancy. It appears that PN-1 mRNA in the uterus and ovary was highly regulated during early pregnancy, which might have an important role in implantation of rat blastocysts. PN-1 was localized in endometrial stromal cells of the uterus and in granulosa cells of the unstimulated primary follicles in the ovary during periimplantation period. Also, PN-1 mRNA expression was higher at implantation period than that at nonimplantation period of pregnancy. In conclusion, PN-1 is expressed in female reproductive tracts and highly regulated during implantation and early pregnancy.
authors.affiliation: Department of Biochemistry and Institute for Clinical Research, College of Medicine, Pochon CHA University, 351 Yatap-dong, Pundang-ku, Sungnam 463-712, South Korea. nkkim@netsgo.com
authors.forename: N K
authors.initials: NK
authors.lastname: Kim
authors.forename: M J
authors.initials: MJ
authors.lastname: Choi
authors.forename: H M
authors.initials: HM
authors.lastname: Chung
authors.forename: T J
authors.initials: TJ
authors.lastname: Sohn
authors.forename: S G
authors.initials: SG
authors.lastname: Hwang
authors.forename: D
authors.initials: D
authors.lastname: Oh
authors.forename: H H
authors.initials: HH
authors.lastname: Lee
authors.forename: Y H
authors.initials: YH
authors.lastname: Lee
authors.forename: J J
authors.initials: JJ
authors.lastname: Ko
mesh_terms: D016564:Amyloid beta-Protein Precursor; D000818:Animals; D002352:Carrier Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D010064:Embryo Implantation; D004717:Endometrium / Q000201:enzymology; D004790:Enzyme Induction; D005260:Female; D005865:Gestational Age; D006107:Granulosa Cells / Q000201:enzymology; D017403:In Situ Hybridization; D008297:Male; D009928:Organ Specificity; D010053:Ovary / Q000201:enzymology*; D011247:Pregnancy; D058255:Protease Nexins; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011956:Receptors, Cell Surface; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017154:Stromal Cells / Q000201:enzymology; D014599:Uterus / Q000201:enzymology*
chemical_list: D016564:Amyloid beta-Protein Precursor; D002352:Carrier Proteins; D058255:Protease Nexins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface