Expression of plasma membrane alkaline phosphatase in normal and regenerating choriocapillaris in the rabbit

Ultrastructural histochemistry for plasma membrane nonspecific alkaline phosphatase was performed on the normal and regenerating choriocapillaris (CC) of rabbits. In normal animals the CC endothelium expressed little or no staining, whereas in regenerating CC the endothelium exhibited staining. The staining was most intense at the unfenestrated plasma membrane. As the capillaries matured and the fenestrated plasma membrane became more extensive, the staining was reduced and eventually eliminated. Pericytes did not stain in normal or regenerating CC.