[The postnatal development of synapses at the dendrites of rabbit mitral cells]

Olfactory bulbs from 4 specimen of the 1st, 4th, 6th, 9th and 60th postnatal day were used. Relative mature unidirectional and reciprocal synapses are present at the mitral cell dendrites already at the first day. During postnatal development the amount of electrondense postsynaptic material increase. The vesicles were always spheric; their number increase significantly with age only at granule cell side of the reciprocal synapses. Length and width of the synaptic cleft do not change with age.