THE PRESENCE OF PROLIDASE ACTIVITY IN AMNIOTIC-FLUID AND ITS EVALUATION AS A MATURITY TEST

Prolidase (EC: 3.4.13.9) catalyses the hydrolysis of the peptide bond involving the imino nitrogen of proline or hydroxyproline. Because of the high proportion of imino acids in collagen, this enzyme plays an i mportant role in its degradation. Since collagen turnover rate is expe cted to be high during fetal growth, the level of prolidase activity m ay reflect the degree of fetal maturation. In this study, amniotic flu id prolidase I activity was measured in term and preterm pregnancies. Lecithin concentration, which has been widely used for predicting feta l lung maturity, was also measured. Prolidase I activity was positivel y correlated with lecithin levels (n = 30; r = 0.42; p < 0.02), and al so with birth weight of the babies (n = 30; r = 0.52; p < 0.01) in the term-mature group. Dysmature babies had significantly lower prolidase I activity in the amniotic fluid which was thought to be indicative o f growth retardation.