抄録
We performed ultracytochemical studies of Mg-ATPase and TPPase activities in circumventricular capillaries at the developmental stage of rats, from 17 gestational days to 8 postnatal weeks, comparing with hippocampal capillaries. During the course of perinatal development, the predominant localization of both enzymatic activities, particularly Mg-ATPase, in circumventricular capillaries was shifted from the luminal cell membrane to the antiluminal cell membrane. In all hippocampal capillaries observed, the predominant localization of both enzymatic activities was the antiluminal cell membrane. It was suggested that immaturity of circumventriculr capillaries may be one of the causative factors inducing intraventricular and subependymal hemorrhages in neonates.
