Reference ranges of matrix metalloproteinase-1, -2, -9 and tissue inhibitor of matrix metalloproteinases-1 concentrations in amniotic fluid in physiological pregnancy

The aim of this study was to determine reference values of matrix metalloproteinase-1 (MMP-1), MMP-2, MMP-9 and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) in the amniotic fluid at the first stage of labor in physiological pregnancy. 89 women at the first stage of term labor have been examined. Samples of amniotic fluid were taken at the first period of labor by vaginal amniotomy. Concentrations ofMMP-1, MMP-2, MMP-9, and TIMP-1 were investigated in amniotic fluid by ELISA kits. We have determined normal concentration ranges for MMP-1, MMP-2, MMP-9, TIMP-1, and ratios of concentrations of MMPs and TIMP-1 (MMP-1/TIMP-1, MMP-2/TIMP-1, MMP-9/TIMP-1) in the amniotic fluid at the first period of labor in physiological pregnancy. These included: MMP-1 - 5.1-16.8 pg/mg of protein, MMP-2 - 238.3-374.1 pg/mg of protein, MMP-9 - 66.1-113.3 pg/mg of protein, TIMP-1 - 4.7-13.6 pg/mg of protein, ratio of MMP-1/TIMP-1 - 0.1-2.2, ratio of MMP-2/TIMP-1 - 19.9-55.7, ratio of MMP-9/TIMP-1 - 4.2-17.2.