Effect of fluorodeoxyuridine on neurons and non-neuronal cells in cerebral explants

Abstract

Fetal rat brain neurons are reported to show enhanced neurite development when treated with the mitotic inhibitors fluorodeoxyuridine (FUdR) or cytosine arabinoside (AraC). For AraC-treated rat cerebral explants, increased neurite growth occurs along with a change in the composition of the non-neuronal cell population and diminished non-neuronal cell proliferation. FUdR-treated rat cerebral explants were therefore cultured in an attempt to determine whether FUdR encourages neurite outgrowth by changing the composition and number of non-neuronal cells. Quantitative morphological analyses revealed a significant decrease in the incidence of non-neuronal cells, and an increase in neurite outgrowth for the FUdR-treated explants. These explants also exhibited an increased proportion of protoplasmic astrocytic-epithelial cells and a decreased proportion of fibroblastic-reactive microglial cells. Thus, FUdR may encourage neurite outgrowth through a curtailment of non-neuronal cell proliferation (primarily by fibroblastic-reactive microglial cells) and through the creation of a non-neuronal cell environment consisting almost entirely of protoplasmic astrocytes.