A Study of Localization of Alkaline Phosphatase Activity in Endometrium of Mouse Uterus During Estrous Cycle

This study has been done in order to verify the localization of alkaline phosphatase(ALP) activity, in connection with the mechanism of seceretion and absorption of luminal fluid in the mouse uterus during estrous cycle. The localization of ALP has been carried out by using a modified Ernst(1972)¹²⁾ method. The results of these experiments were as followings: The reaction product by ALP activity was localized in general at the luminal and glandular epithelia, and the wall of blood vessels of endometrium. At diestrus stage, luminal surface and basal lamina of the epithelia showed a moderate reaction products by ALP activity. However, the intensity of ALP activity was not even according to the region. As the cyclic stage transited from proesturs to estrus the reaction product at the basal lamina region and on the luminal surface, which showed a lot of well developed microvilli, appeared gradually heavier to be come maximum at estrus stage. It is implying that the most active transport of luminal fluid occurs at these region during estrus stage. At metaestus stage, the reactive product at the same sites as estrus stage appeared light with some symptomes of degeneration. Some of secretory cells on the luminal epithelium had mitochondria with dense granules in their matrix. Therefore, from the above result it is strongly suggested that the chages in the localization and intensity of ALP activity on the luminal and glandular epithelia, and blood vessels might be closely correlated with the secretion and absorption of the luminal fluid in the uterus during estrous cycle.