Abstract
To determine the ultracytochemical localization of alkaline and acid phosphatase activities of normal rat choroidal epithelium, the lead citrate method after Mayahara, for the former and the Gomori's method for the latter were used.
The electron dense reaction products of alkaline phosphatase activity are found only along the basal plasmalemma and in the wall of capillary endothelium in the choroid plexus. The activity of acid phosphatase is limited to the lysosomes and the inner cisternae of the Golgi lamellae.
The possible function of these two enzymes was briefly discussed.
