Mice: 16alpha-Bromoepiandrosterone (HE2000) or vehicle (0.1 ml) was delivered by various routes (s.c. injection, oral gavage or buccal administration) 24 h before and 1 h after bacterial challenge. When mice (three to five per group) treated orally with HE2000 (40 mg/kg given) were challenged with LPS, the numbers of infiltrating cells in BAL at 48 h were reduced significantly. HE2000 (120 mg/kg) increased significantly numbers of lymphocytes in the PLN 7 days after the footpad was injected with the compound and a nonsensitizing dose of TNP–OVA.

16alpha-Bromoepiandrosterone (HE2000) inhibits nitric oxide production by LPS-stimulated RAW 264·7 cells. HE2000 (0.03–3 uM) had no significant effect on either cell proliferation or NO production by resting (unstimulated) RAW264·7 cells. HE2000 alone did not effect cell proliferation in LPS-stimulated cultures. When HE2000 was cultured with LPS-stimulated RAW264·7 cells for 6, 28 h or 48 h, a dose-dependent inhibition of NO production was observed. Optimal inhibition was observed at the 24-h time point. HE2000 appears to limit NO production with an inhibitory concentration 50% (IC50) of approximately 1 uM.