The formation of capillary basement membranes during internal vascularization of the rat's cerebral cortex.

摘要: The vascularization of the parietal-temporal region cerebral hemispheres has been studied in a total 50 rats from day 11 gestation up to adults. first extracerebral vessels constituting primary perineural vascular network and intracerebral on 12–14 show sinusoid characteristics, i.e. irregular thickness endothelial wall perforated by fenestrations or small holes showing, if at all, beginning accumulation basement membrane (BM) material. No paired have observed which would be expected internal cortical anlage starts penetrating loops. Immature capillaries developing sprouting (and) preexistent begin appear about 15 gestation. further differentiation terminal bed establishing definitive architecture is accompanied maturation tissue, diminution extracellular spaces, perivascular, astroglial neuronal elements including development synapses. continuous process BM-formation appearance until postnatal thickening described four successive stages: Stage 1. Local accumulations fine filamentous material between endothelium opposite perivascular surfaces sinusoids sprouts. 2. Delicate networks filaments attached endothelial, pericytal adjacent glial plasma membranes (PM) immature capillaries, plaques lamina densa narrow clefts. 3. A thin adapted PM; its are arranged parallel cell surface. In this plane they run randomly. rara only few PM mainly perpendicular: stage capillaries. 4. Thickened densa, condensed pattern; zone rara: mature Coincidental with rapid BM 3rd–4th week characteristics capillary growth change: intensive finished length increases nearly proportionally tissue volume later on. It suggested that plays role regulating mitotic division cells.