MATRIX METALLOPROTEINASE EXPRESSION DURING MOUSE PERIIMPLANTATION DEVELOPMENT

PROBLEM: The purpose oi this study was to define the temporal expressi on and to quantitate the mRNA levels of collagenase, 72 kDa. 92 kDa, a nd membrane-type matrix metalloproteinases during the peri-implantatio n period of pregnancy in the mouse uterus. Embryonic expression of 72 kDa and 92 kDa matrix metalloproteinases, as well as interleukin 1 alp ha, was also investigated, METHODS: Uterine matrix metalloproteinases we detected using gelatin substrate gel electrophoresis (zymography) a nd reverse-transcription polymerase chain reaction methodology was use d to detect and quantitate different mRNA species in the mouse uterus and blastocyst. RESULTS: Collagenase, 72 kDa, and 92 kDa matrix metall oproteinases are developmentally regulated during the peri-implantatio n period of pregnancy, but membrane-type matrix metalloproteinase appe ars to be expressed constitutively. Matrix metalloproteinase mRNA leve ls have been quantitated and confirm the observed developmental expres sion patterns. Prominent expression of both 92 kDa matrix metalloprote inase and interleukin 1 alpha was observed in blastocysts during outgr owth while weak expression of the 72 kDa matrix metalloproteinase was detected. CONCLUSIONS: The data provide evidence of matrix metalloprot einase expression in vivo and substantiate their potential role in tis sue remodeling prior to and during blastocyst implantation. Expression of interleukin 1 alpha, 92 kDa, and 72 kDa matrix metalloproteinases suggest that these proteins are important or trophoblast invasion asso ciated with implantation of the early embryo.