Ten daily doses of ethanol exposure reduced neurogenesis in hippocampal dentate gyrus during combined ethanol and LPS treatments. Male C57BL/6J mice were treated intragastrically with ethanol (5 g/kg, i.g.) for either 1 day or 10 days and injected intraperitoneally (i.p.) with LPS (3 mg/kg, i.p.) 24 hrs after ethanol treatment. Mice were sacrificed 1 hr following saline or LPS administration. Brain sections were fixed and stained with anti-mouse PCNA (a marker for proliferation of neural progenitor cells) and anti-goat doublecortin (a marker for immature or newly born neurons) antibodies. (A) Ethanol (5 g/kg, i.g., 1 day) pre-treated group, LPS did not show a decrease in the number of PCNA and doublecortin-IR cells. (B) Ethanol (5 g/kg, i.g., 10 days) pre-treated mice, LPS significantly decreased PCNA and doublecortin-IR cells, suggesting that 10 daily doses of ethanol inhibits neurogenesis during combined ethanol and LPS treatments. (C) The pictures represent PCNA-IR cells in control (upper panel) and ETOH-LPS treated (lower panel) dentate gyri of the hippocampus. (D) Representative pictures of doublecortin (DCX) immunoreactivity. DCX expression was shown in control brain (upper panel) and ETOH-LPS treated brain (lower panel).