Protective effect of bis-pyridinium compounds on the rat brain acetylcholinesterase inhibition by carbamate in vitro.

The inhibition of the rat brain acetylcholinesterase by quaternary bis-pyridinium compounds and the protection against acetylcholinesterase inhibition by 3-diethyl-aminophenyl-N-methylcarbamate methiodide was studied with three bis-pyridinium compounds. These compounds have two pyridinium rings connected by a dimethylether link and alkyl groups in position 4 of both pyridinium rings. Toxogonin was used as a reference compound. Bis-pyridinium compounds studied are weak reversible inhibitors of acetylcholinesterase (I50 from 10(-4) to 10(-3) M) and exert also the ability to protect acetylcholinesterase against inhibition by 3-diethyl-aminophenyl-N-methylcarbamate methiodide in vitro at a concentration of 0.1 mM. Negligible protection was obtained with Toxogonin.