[Comparative sensitivity of the sympathetic and parasympathetic ganglia to ganglionic blockaders]

Pharmacological tests in vitro on the cat isolated superior cervical and ciliary ganglia identified the IEM-1194 as a selective parasympathetic ganglion-blocking agent. The ganglion-blocking activity of this drug was three times as high in parasympathetic ganglion (EC50 = 1.15 +/- 0.34 M/1 x 10(-5)) as in sympathetic one (EC50 = 3.2 +/- 0.2 M/1 x 10(-5)). I. v. administration of the IEM-1194 in a dose effectively (50%) blocking responses of the heart (bradycardia) and duodenum (peristaltics) to vagal stimulation, did not lower arterial blood pressure.