An ultrahistochemical study of the distribution of acid and alkaline phosphatases in placentae from normal and complicated pregnancies
An ultrahistochemical study of the distribution of acid and alkaline phosphatases in placentae from normal and complicated pregnancies
复制标题
正常和复杂妊娠胎盘中酸性和碱性磷酸酶分布的超组织化学研究
作者：
Carolyn J. P. Jones;H. Fox
酸性和碱性磷酸酶的亚细胞定位已在正常和复杂妊娠的胎盘滋养层中进行了研究。在无并发症妊娠的胎盘中，随着妊娠的进行，含有滋养层酸性磷酸酶的细胞器的数量逐渐减少，而碱性磷酸酶活性虽然在足月时丰富，但在妊娠早期无法表现出来。含有酸性磷酸酶的细胞器有两种类型：一个是小圆形体，可能是溶酶体，而另一个是多泡体。碱性磷酸酶主要分布在合胞体微绒毛和质膜上。有人认为，妊娠早期显着的溶酶体活性与胎盘在此期间的结构重塑有关，并且滋养层中存在两种与磷酸酶相关的转移系统，一种依赖于含有酸性磷酸酶的多泡体并在妊娠早期使用，另一种依赖于碱性磷酸酶并在妊娠后半期占主导地位。在长期妊娠的胎盘中，滋养层酸性磷酸酶进一步下降，而碱性磷酸酶活性通常持续增加。在低出生体重婴儿的胎盘中，这种趋势有时会逆转，碱性磷酸酶活性要么消失，要么其反应产物扩散到整个合胞体；这通常伴随着含酸性磷酸酶的多泡体数量的显着增加。先兆子痫女性的胎盘未显示碱性磷酸酶活性丧失，但其特征是溶酶体数量增加。
The subcellular localisation of acid and alkaline phosphatase has been studied in the trophoblast of placentae from both normal and complicated pregnancies. In placentae from uncomplicated pregnancies the number of trophoblastic acid-phosphatase-containing organelles decreases progressively as gestation proceeds whilst alkaline-phosphatase activity, although abundant at term, could not be demonstrated during the early stages of pregnancy. The acid-phosphatase-containing organelles are of two types; one is a small round body which is probably a lysosome whilst the other is a multivesicular body. The alkaline phosphatase is distributed mainly on the syncytial microvilli and plasma-membrane. It is suggested that the marked lysosomal activity during early pregnancy is related to the architectural refashioning of the placenta during this period and that there are two phosphatase-linked transfer systems in the trophoblast, one dependent upon acid-phosphatase-containing multivesicular bodies and being utilised during early pregnancy and the other reliant upon alkaline phosphatase and dominating during the second half of gestation. In placentae from prolonged pregnancies there is a further decrease in trophoblastic acid phosphatase and, usually, a continuing increase in alkaline-phosphatase activity. In placentae from babies of low birth weight this trend is sometimes reversed and alkaline-phosphatase activity either disappears or its reaction product diffuses throughout the syncytium; this is usually accompanied by a marked increase in the number of acid-phosphatase-containing multivesicular bodies. Placentae from women with pre-eclampsia show no loss of alkaline-phosphatase activity but are characterised by an increased number of lysosomal bodies.