Abstract In the search for new positive inotropic agents we have investigated a series of 3- dimethylamino-1, 2, 3, 4-tetrahydroquinolines with various substituents on the nitrogen of the quinoline ring. The N-isobutyryl derivative 20 (S903) was selected as the most interesting compound. Interestingly, while cardiac contractility was increased in vitro, heart rate was unchanged or slightly decreased. The positive inotropic activity was partly dependent on ...
