Activity of Placental β‐N‐Acetyl‐Glucosaminidase in Cows with and without Retained Fetal Membranes

Abstract

Contentsβ‐N‐acetyl‐glucosaminidase (Nagase) is one of the enzymes responsible for the metabolism of proteoglycans. It may take part in cell‐to‐cell adhesion processes and might be involved in creating the attachment between the maternal and fetal parts of the bovine placenta. The aim of the following study was the determination of Nagase activity in bovine placental tissues and the comparison of this activity between animals releasing and retaining fetal membranes. The experiment was performed on animals divided into six groups as follows: A, caesarian section before term without retained fetal membranes (n = 14); B, caesarian section before term with retained fetal membranes (n = 14); C, caesarian section at term without retained fetal membranes (n = 15); D, caesarian section at term with retained fetal membranes (n = 8); E, spontaneous delivery at term without retained fetal membranes (n = 16); F, spontaneous delivery at term with retained fetal membranes (n = 10). The enzyme activity was determined spectrofluorimetrically and expressed in nkat/mg protein. Nagase activity increased during last few days before parturition. The activity in general was lower in the fetal than in the maternal part of placenta (in five out of six) of the examined groups of animals. In the maternal part of term placenta, enzyme activity was statistically significantly higher in cases of retained fetal membranes than in control cows. In the fetal part of term placenta the opposite relationship was observed. The results obtained may indicate the involvement of Nagase in the processes of releasing/retaining bovine fetal membranes. Further experiments are necessary in order to explain the mechanisms and substances responsible for controlling the enzyme activity in the placenta.