Developmental changes of K+-dependent para-nitrophenylphosphatase (Na+-K+-ATPase) distribution in the synaptic regions in the cerebral cortex of rats

Using Mayahara's method, the distribution of K+-dependent p-nitrophenylphosphatase activity was examined electron microscopically in the synaptic regions of the cerebral cortex of 10, 15 and 60-day-old Wistar rats. The enzyme achieved gradually its characteristic localization and uniform distribution. The main developmental changes were associated with the establishment of the postsynaptic density's activity. The controls with ouabain revealed activity only on the postsynaptic densities.