Effect of azelastine on activation and release stages of allergic histamine secretion in rabbit basophils.
In this study the effect of azelastine on the activation (antigen-dependent, Ca(2+)-dependent, Stage I) and release (antigen-independent, Ca(2+)-dependent, Stage II) phases of allergen-induced histamine secretion in rabbit mixed leukocytes (basophils) was investigated. Azelastine (5 microM, 10-min) and diltiazem (5 microM: a Ca2+ antagonist, 10 min) inhibited ragweed extract-induced histamine secretion during the Stage II (release) phase. Theophylline (100 microM), a phosphodiesterase inhibitor, added immediately before antigen challenge, inhibited allergic histamine secretion during the Stage I (activation) phase. The data obtained in this study suggest that diltiazem and azelastine act on the Ca(2+)-dependent and antigen-independent phase (Stage II) of allergic histamine secretion in rabbit basophils.
Chand
N
N
Department of Pharmacology, Wallace Laboratories Division of Carter-Wallace, Inc., Cranbury, New Jersey 08512.
Pillar
J
J
Diamantis
W
W
Sofia
R D
RD
D000818:Animals; D001491:Basophils / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000502:physiology; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D006636:Histamine Release / Q000187:drug effects*; D049673:History, 20th Century; D006967:Hypersensitivity / Q000378:metabolism*; D010793:Phthalazines / Q000494:pharmacology*; D011817:Rabbits
D006634:Histamine H1 Antagonists; D010793:Phthalazines; D002118:Calcium; C020976:azelastine