Sinapsi dendro-dendritiche ed altre sinapsi in sferule riaggregate e coltivate in vitro di bulbi olfattori di embrione di pollo

Stefanelli, Alberto ; Cataldi, Emilia ; Ieradi, Luisanna

Atti della Accademia nazionale dei Lincei. Rendiconti della Classe di scienze fisiche, matematiche e naturali, Série 8, Tome 61 (1976) no. 6, pp. 653-660

Résumé

Well differentiated neurons and glial cells are visible within globular structures of about $200 \mu$ diameter, obtained from a aggregation of disaggregated olfactory bulbs of chicken embryos, 10 days' incubation old, and cultivated in the “rotating shaker” for 20 days. Particularly recognizable are mitral cells and granule cells (amacrine). Electron microscopy reveals different kinds of synaptic profiles: axo-dendritic, axo-somatic and dendro-dendritic. Of particular interest is the finding in the cultivated globules of this last type of synapse between mitral cell dendrites and dendrites of the granule cell, because it is clearly evident that this type of synapse is not produced here by any excitement derived from peripheric input (from fila olfactoria) in this case completely lacking, as it is proposed by physiological works, but is the expression of an intrinsic capability of the coupled neurons, acquired at the moment of the specific hystogenetic determination at an embryonal stage, earlier than the stage of disaggregation. Many peculiar morphological data of these dendro-dentritic synapses are described and discussed.