Genesis, structure and transit of dense bodies in rat neocerebellar cortical cells, namely Purkinje neurons: an ultrastructural study.
This work is an attempt to shed some light on a controversial matter that has divided the opinion of neuroscientists concerned with the genesis of dense bodies. Our opinion supports the mitochondrial origin of dense bodies not only in Purkinje cells, but in the common granule cells of the granular layer and in regional astrocytes of the Purkinje cell layer (the Bergmann cells) as well. In a second stage, other organelles (namely lysosomes) seem to become incorporated into structures which progressively increase their size and their heterogeneity. Additionally, two distinct types of dense bodies were observed in Bergmann cells; the hypothesis of one type being endogenous (i.e., of local production) and the other exogenous (i.e., imported from Purkinje cells) as well as the possibility of dense body discharge from the glia towards endothelia is thoroughly discussed. Finally, some physiological implications in connection with lipofuscin accumulation are analysed.
Monteiro
R A
RA
Department of Microscopical Morphology, University of Oporto, Portugal.
D000375:Aging; D000818:Animals; D002525:Cerebellar Cortex / Q000254:growth & development / Q000648:ultrastructure*; D005260:Female; D008561:Membrane Fusion; D008854:Microscopy, Electron; D008928:Mitochondria / Q000648:ultrastructure; D015388:Organelles / Q000502:physiology / Q000648:ultrastructure*; D011689:Purkinje Cells / Q000502:physiology / Q000648:ultrastructure*; D051381:Rats; D011919:Rats, Inbred Strains