RT Journal Article SR Electronic T1 The effects of LY293111Na, a leukotriene B4 receptor antagonist, on the pulmonary neutrophilia and CD11b expression caused by inhalation of a leukotriene B4 aerosol in rhesus monkeys. JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 341 OP 349 VO 277 IS 1 A1 D L Allen A1 W P Hoffman A1 P Marder A1 M R Matchett A1 P A Leiter A1 D L Abbott A1 R K Wolff YR 1996 UL http://jpet.aspetjournals.org/content/277/1/341.abstract AB The dose-response relationship between aerosolized leukotriene B4 (LTB4 and pulmonary neutrohilia was examined in a group of five rhesus monkeys. The effects of an oral dose of LY293111Na on LTB4-aerosol-induced pulmonary neutrophilia were also examined. Ex vivo expression of CD11b receptors on polymorphonuclear leukocytes from bronchoalveolar lavage fluid and peripheral whole blood were also assessed. Up-regulation of CD11b adhesion receptors by LTB4 was assessed ex vivo on the peripheral whole blood. Pulmonary neutrophilia was linearly associated with dose of inhaled LTB4. LY293111Na, at 10 mg/kg, significantly blocked the profound bronchoalveolar lavage neutrophilia produced by LTB4 aerosol inhalation. A large (48%), but not statistically significant, reduction was seen for CD11b expression on bronchoalveolar lavage polymorphonuclear leukocytes after pretreatment with LY293111Na. LY293111Na did not significantly change the number of white blood cells in peripheral blood. LY293111Na did significantly attenuate the LTB4-induced up-regulation of CD11b receptors on peripheral blood neutrophils. We conclude that LY293111Na may be an effective oral treatment for diseases that involve neutrophilic inflammation.