Figure 3

LTB ₄ via i.c.v. suppresses antigen-induced eosinophil infiltration in lung tissue. A-D are representative histopathological pictures of lung. Compared with NS-vehicle (A), there is a marked infiltration of eosinophil cells in the peribronchiolar space and perivascular space in the OVA-vehicle group (B). LTB₄, 30 ng via i.c.v. injection, significantly inhibited OVA-induced eosinophil cell infiltration (C). U75302 (100 ng pretreatment via i.c.v.) blocked the inhibitory effect of LTB₄on eosinophil cell infiltration (D). Eosinophil cell infiltration was scored based on the severity of inflammation (E). A non-parametric test, the Mann--Whitney U-test, was used to compare differences in eosinophil cell infiltration in lung tissues. Data are expressed as mean ± S.E.M. (n = 8 per group). ^##P < 0.01 vs. the NS-vehicle group;**P < 0.01 vs. the OVA-vehicle group; ^††P < 0.01 vs. the OVA-LTB₄ 30 ng group. OVA, ovalbumin; NS, saline.