Effects of brovincamine on the autonomic nervous function in the dog and rat

Effects of brovincamine (BV) on peripheral nerves were studied in dogs and rats. 1) In pentobarbital-anesthetized dogs, BV (6.4 mg/kg) administered i.v. did not affect the changes of blood pressure and heart rate induced by noradrenaline and adrenaline, but slightly inhibited the hypotensive effect of acetylcholine. BV had no effect on the hypertension elicited by carotid sinus reflex, but diminished the bradycardia by vagus nerve stimulation. BV did not influence the tachycardia elicited by stimulation of the postganglionic nerve to stellate ganglion, but slightly inhibited that by the preganglionic stimulation. 2) In spinal dogs, BV (6.4 mg/kg) given i.v. slightly inhibited the increases of blood pressure and heart rate induced by i.v. dimethylphenylpiperazinium (DMPP). When i.v. administered in divided doses of 2 and 4 mg/kg, BV induced a slight but stepwise inhibition of the tachycardia elicited by direct administration of DMPP, bethanechol (BCH) and angiotension II (AT II) to the cardiac sympathetic ganglia via the subclavian artery. 3) In rat isolated diaphragm nerve preparations, BV at 10(-5) and 10(-4) g/ml dose-dependently reduced the twitch response to nerve stimulation. 4) In conclusion, BV does not affect the sympathetic activities but inhibits the cholinergic function in the autonomic nervous system.