Histamine dihydrochloride 10−6 g/ml for 5 minutes,
Ca-ionophore 5 × 10−6 g/ml for 5 minutes, or
Leukotriene LTC4 (10−9 - 10−8) g/ml for 10 minutes,
To the bath and recording the contractile force at its maximal level. Following 20 minutes, equilibration pe-riod resulted, the spasmogen is administrated again, 5 minutes thereafter, and the test compound is added in cumulative dose from 10 −8 - 10−4 g/ml at 5 or 10 minutes intervals. The contractile response is determined isomet-riccally [18].