Abstract
It has been postulated that beta-adrenergic stimulation leads to an increase in intracellular cyclic AMP level and induces the relaxation of tracheobronchial smooth muscle, and that alphaadrenergic stimulation causes bronchoconstriction.
The present investigation was conducted to explore the effect of pretreatment of asthmatic patients using imidalin, an alpha-adrenoreceptor blocking agent, on salbutamol-induced improvement in various pulmonary bronchoconstriction.
The present investigation was conducted to explore the effect of pretreatment of asthmatic patients using imidalin, an alphaadrenoreceptor blocking agent, on salbutamol-induced improvement in various pulmonary function tests and the increase of plasma cyclic AMP levels.
1) Comparing the pulmonary function tests between the control group in which salbutamol alone was administered and the imidalin group in which salbutamol was administered after pretreatment with imidalin, R.r., FEV1.0 and V05 showed significant improvement in both groups and the extent of improvement in the imidalin group was greater than that in the control group.
2) The pulmonary function tests in the control group and in the imidalin group showed the greatest improvement 80min after the oral administration of salbutamol, and the extent of improvement in the imidalin group was greater than that in the control group
3) The plasma cyclic AMP level increased significantly after the oral administration of salbutamol alone, but the extent of the increase became more dominant after imidalin pretreatment, .
4) As for side effects in the salbufamol-only group five cases complained of palpitation, headache and giddiness but these side effects were not seen after pretreatment with imidalin.
The above results may suggest that imidalin, an alpha-adrenergic blocking agent, can be used for the treatment of bronchial asthma in combination with various beta-adrenergic stimulating agents.
