Ultrastructural organization of normal and transplanted rat fascia dentata: I. A qualitative analysis of intracerebral and intraocular grafts

摘要: Few studies have dealt with the general ultrastructure and synaptic organization of grafted brain tissue. This study was therefore performed to extend current light microscopic observations on intracerebral intraocular grafts hippocampal tissue ultrastructural level. Blocks containing hippocampus fascia dentata from day 21 embryonic rats were into developing adult anterior eye chamber rats. After 100 or 200 days survival recipient rat brains eyes processed for electron microscopy. Tissue graft dentate molecular layer adjacent granule cell selected analysis, together a few samples hilus CA3. Normal analyzed as control. At level most displayed an organotypic clearly recognizable neuropil layers. Under microscope cells had normal-appearing dendrites bearing normal types spines forming synapses. case even in absence major extrinsic afferents like perforant path. The formed axons terminals characteristics mossy fiber system CA3, addition aberrant supragranular known transplants. Abnormal structures included dendritic growth cones increased occurrence polyribosomes spines. Their indicates ongoing plasticity after transplantation. There also density glial elements, particularly grafts. In some these immature traits terms nuclear indentations. Dentate interneurons basket type present both grafts. We conclude that cells, different surroundings without normal, path input, can develop basically cellular morphology, which includes synapses, fibers its terminals.