Antiallergic agent, azelastine, inhibits (45)Ca uptake and histamine release in rat mast cells stimulated by antigen

The effect of antiallergic agent, azelastine, was examined in immunogical secretory process of mast cells. 1. Azelastine significantly inhibited (45)Ca uptake by mast cells stimulated by antigen, and the maximum inhibition was attained at a concentration of 50 μg/ml showing approximately 30.5 % inhibition. 2. Azelastine also inhibite the release of histamine from mast cells by antigen. The maximal inhibitory rate was 38.1%. The effect of azelastine on (45)Ca uptake and histamine release was dose-dependent, and compatible at employed cocentration of the agent. 3. Tachpylaxis to azelastine was not found in this experimental system.

抗原刺激時の,ラット腹腔肥満細胞のCa(2+) uptakeおよびヒスタミン遊離に対する,抗アレルギー薬アゼラスチンの抑制効果について検討を加えた｡その結果,1.アゼラスチンは抗原刺激時の肥満細胞のCa(2+) uptakeに対して濃度依存性の抑制効果を示した｡2.同様に,抗原刺激時の肥満細胞からのヒスタミン遊離に対しても,濃度依存性の抑制効果を示した｡3.アゼラスチンの再暴露による抑制効果の減弱傾向は見られず,アゼラスチンでは　tachyphylaxisは観察されなかった｡