Replication of centrioles and differentiation of neurons in hippocampal slice cultures and olfactory neuroepithelium in the rat.

The role of centrioles in the development of neurons was investigated. During the first 2 weeks of cultivation of hippocampal neurons, the number of centrioles increased to 13 +/- 4 per cell (mean +/- SEM). After 3 weeks, the number decreased and neurons only rarely contained more than four centrioles. Multiple centrioles aggregated into a compact single ellipsoid with long and short axes of 4.1 +/- 0.1 microns and 2.2 +/- 0.2 microns. Thus, replication and accumulation of centrioles preceded neurite extension, which occurred from the 20th day onward. The data suggest that centrioles organize the rearrangement of the microtubule network, thus driving neuronal differentiation and especially axon and dendrite formation.