[On the cholinolytic activity of pramiverine]

Pharmacological experiments with the spasmolytic 4,4-diphenyl-N-isopropyl-cyclohexylamine hydrochloride (pramiverine, Sistalgin) are reported. The anticholinergic and spasmolytic action was tested in vitro on segments of abdominal organs in comparison with atropin, hyoscin-N-butylbromide and Eupaverin. Acetylcholine, arecoline, carbachol and pilocarpine were used as cholinergic agonists. Besides, neostigmine was applied. Pramiverine is distinguished by a strong anticholinergic and a papaverine-like spasmolytic component. In vitro the anticholinergic action of pramiverine on the small intestine (guinea pig, rabbit), gall bladder (guinea pig) and uterus (guinea pig, rat) was equally strong as the effect of atropine, but on the urinary bladder (guinea pig) the effect was 5 times weaker. The anticholinergic effect was also demonstrated in other models: intestinal spasms after neostigmine injection in the guinea pig; hypotensive effect after acetylcholine administration in rabbits, cats and dogs; salivation after pilocarpine administration in rabbits; tremorine test in rats. The gastric secretion in the Shay rat and the gastrointestinal passage were reduced or inhibited by pramiverine. The test substance was also active on oral application.