Effect of azelastine on the down regulation of beta-adrenoceptors in guinea pig lung.
The new antiallergic drug azelastine (E-0659, Azeptin; CAS 58581-89-8) is used in the treatment of rhinitis and bronchial asthma. In the present study, the effect of azelastine on the regulation of the beta-adrenoceptors and the down regulation of beta-adrenoceptors by terbutaline, a beta-agonist, was investigated using guinea pig lungs. Guinea pigs were divided into four groups; (1) the control (saline-treated) group, (2) the terbutaline-treated group, (3) the azelastine-treated group, (4) terbutaline plus azelastine-treated group. Guinea pigs intramuscularly injected with each agent three times a day for successive 7 days. In the terbutaline-treated group, a 26% reduction in the number of beta-adrenoceptors compared with those of the control group was observed. In the azelastine-treated group, the number of beta-adrenoceptors increased by 24% compared with those of the control group. The number of the beta-adrenoceptors in the terbutaline plus azelastine-treated group was significantly increased compared with that of the terbutaline-treated group. These results suggest that azelastine may prevent the down regulation observed during beta-agonist administration by increasing the number of beta-adrenoceptors.
Department of Internal Medicine, 1st Affiliated Hospital of Nanjing Medical College, People's Republic of China.
K S
KS
Yin
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K
Hayashi
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F
Taki
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Watanabe
K
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Takagi
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T
Satake
D000818:Animals; D004082:Dihydroalprenolol; D015536:Down-Regulation / Q000187:drug effects*; D006168:Guinea Pigs; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008566:Membranes / Q000187:drug effects / Q000378:metabolism; D010793:Phthalazines / Q000494:pharmacology*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*
D006634:Histamine H1 Antagonists; D010793:Phthalazines; D011943:Receptors, Adrenergic, beta; D004082:Dihydroalprenolol; C020976:azelastine