[Structural and enzyme-histochemical changes of villous trophoblast during pregnancy].

A critical examination of chorion epithel of terminal villi is made on 80 placentas between 8 and 28 as well as 37 and 41 weeks of gestation after a normal pregnancy (clinical and anamnestical) with structural (Carbohydrates, albumines, nucleid-acids) and enzymhistochemical methods. The results of reactions signifies an incontinual morphological and functional differentiation of trophoblast between 16 and 28 weeks. The reduction of Langhanscells and transformation of their predominant degree of differentiation result simultaneously. These changes are discussed in connection with the well known structural and ultra-structural formation processes as well as the functional capacity of plasmodium. This functional-morphological transformation of trophoblasts has reached a qualitative condition by the 28 week, which is corresponding to the placentas of 37 upto 41 weeks by prepondering "ripe" plasmodium and "differentiated" Langhans-cells. Changes with occur in villous-epithel of normal placentas between 28 and 36 week should be predominantly of quantitative nature. The significance of proved Sialic-acid by principal absence of Glykoseaminoglycans in the human placenta will be discussed in connection with the introductions of immunogenity and immunological competence of organs.