[Astroglia formation in the neocortex of mice after temporary prenatal serotonin depletion]

Time-course of astrocyte appearance in the neocortex of F1 (CBA/C57B1) mice after prenatal serotonin depletion was studied. To suppress serotonin synthesis, para-chlorophenylalanine was administered to females once at the early postimplantation stage of gestation. To visualize differentiating astrocytes, the immunohistochemical method for demonstration of astrocyte intermediate filament protein--glial fibrillary acidic protein (GFAP) was used, which allowed not only to label the cells, but also to evaluate the starting point, extent and time-course of their differentiation. The results obtained have shown that in all the neocortical areas studied (area cingularis, area occipitalis, area parietalis, area insularis, area praepiriformis, area piriformis, area entorhinalis and area subiculum), normally, GFAP-positive cells appeared in the layer I at postnatal week 1. In the course of development, the process of astrocyte differentiation was shown to become progressively more intensive. At the same time, the process of barrier structures formation took place. During the first days of postnatal development astrocytes and their processes were shown to appear close to the blood vessels and lateral ventricle walls. In the neocortex of animals that developed during the serotonin depletion, GFAP-positive cells were formed in decreased numbers, in particular, in the white matter, at all the stages of postnatal development studied.