Some properties of human endometrial alkaline phosphatase

A study of some biochemical properties of alkaline phosphatase derived from human endometrium has been undertaken. The endometrial enzyme has been shown to be different from alkaline phosphatases obtained from placenta and small intestine. Endometrial alkaline phosphatase is inhibited by sodium deoxycholate but not by L-phenylalanine; it is completely inhibited by 3 M urea. Magnesium ions have no significant effect on the endometrial enzyme. No differences in biochemical properties were observed when alkaline phosphatase from follicular phase endometrium was compared with that from luteal phase tissue. Acrylamide gel electrophoresis showed a single, constant band of enzyme at all stages of the cycle. It is concluded that, despite the cyclic appearance of alkaline phosphatase in endometrial glands and the constant presence of the enzyme in blood vessels, there is but one variety of alkaline phosphatase in human endometrium.