Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Neurono-glial synaptoid contacts in the median eminence of the rat: ultrastructure, staining properties and distribution on tanycytes
Ist Teil von
Brain research, 1973-10, Vol.61, p.217-234
Ort / Verlag
Netherlands: Elsevier B.V
Erscheinungsjahr
1973
Link zum Volltext
Quelle
Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)
Beschreibungen/Notizen
In the median eminence the existence of neurono-glial synaptoid contacts was confirmed by 3-dimensional reconstructions of electron micrographs. The contacts occur on tanycytes and astrocytes showing a similar ultrastructure. The clear vesicles are ZIO-positive, and the dense projections are impregnated by PTA and BIUL staining. The synaptic cleft is only slightly stained by PTA, but strongly stained by PTAUL and BIUL. E-PTAUL and BIUL staining give similar results. The approximate number and the arrangement of the dense projections were studied. The synaptic contacts differ from most interneuronal synapses in that there are no postsynaptic dense structures. Nevertheless, the presynaptic elements seem to adhere rather strongly to the glial surface. A reconstruction of a part of a tanycyte demonstrated that the ‘active sites’ of presynaptic elements are randomly distributed from the basal parts of the perikaryon to the vascular endfoot. The number of synaptoid contacts on this glial cell was calculated as at least 100. Their structural similarities to and differences from interneuronal synapses and their distribution and functional significance are discussed.