Evaluation of antiasthmatic activity of 7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one in combination with ambroxol in Guinea pigs

In the present study, the antiasthmatic activity of a 7,8,9,10-tetrahydro azepino[2,1-b]-quinazolin-12(6H)-one (TAZQ) and established mucolytic agent ambroxol, alone and in combination, in ovalbumin induced asthma in guinea pigs. TAZQ turned to be a potent bronchodilator when studied in in vitro tracheal strip preparation of sensitized guinea pigs against antigen induced contraction accompanied with notable antioxidant and anti-inflammatory activity at both 10 and 20 mg/kg doses. Ambroxol at the dose of 50 and 100 mg/kg found to possess potent antioxidant activity but devoid of any effect when studied for in vitro bronchodilatory or antigen induced bronchial hyper-responsiveness. The title compound in low dose combination with ambroxol significantly inhibited ovalbumin-induced airway hyper-responsiveness. The combination of two notably reduced eosinophilic infiltrations into lung and bronchoalveolar lavage fluid of sensitized animals signified the synergistic anti-inflammatory activity without any increase in bronchodilator activity of TAZQ. For relief in asthma attacks, presently studied bronchodilator mucolytic combination may be an effective treatment of choice that will take care of bronchoconstriction, bronchial inflammation, and restricted bronchial airflow due to mucus plugging into the bronchioles in acute and chronic asthma.