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-nitropheny lphosphatase activity was examined electron microscopically in the syn aptic regions of the cerebral cortex of 10, 15 and 60-day-old Wistar r ats. 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 con trols with ouabain revealed activity only on the postsynaptic densitie s.