Changes of the uterine proteoglycan distribution at term pregnancy and during labour

Abstract

Objective: To characterise uterine proteoglycans and changes therein during pregnancy and labour. Study Design: Uterine samples were collected from 6 non-pregnant, 10 term-pregnant and from 10 women in active labour. The proteoglycans were extracted by 4M guanidine hydrochloride and precipitated with Alcian Blue. They were separated by electrophoresis and identified by Western blotting. Results: Decorin was the dominating proteoglycan and smaller amounts of biglycan was found. A considerable amount of heparan sulphate proteoglycans was also detected. Decorin and biglycan decreased by 40% until term. The amount of heparan sulphate proteoglycans increased by 46% during active labour. Conclusion: Our data indicate that a considerable remodelling of the uterine connective tissue occurs during pregnancy and labour. The decrease of decorin and biglycan and the increase of heparan sulphate proteoglycans may be important for normal myometrial contractions during labour.