Protective effect of some pyridinium salts on acetylcholinesterase against organophosphate inhibition.

The protective effect of ten new synthetized mono- and bis-pyridinium salts on acetylcholinesterase (AChE) against DFP, Chlorphenvinphos, DDVP, IPO 62 and IPO 63 inhibition in vitro and in mice i.p. was studied. Moreover, abolition of tetanic block of the tibialis anterior muscle in rats after intoxication with DDVP by these salts was tested. An increase of the therapeutic effect of atropine after DFP poisoning in mice and a rise of LD50 values from 1.4 (PAN-W-15) to 5.1 times (PAN-W-14) was noted. The effect of PAN-W-14 and PAN-W-18 after inhibition by other organophosphates was found to be highest in human erythrocytes in vitro. In addition, prophylactic administration of PAN-W-14 prevented the tetanic block of the muscle in situ after DDVP intoxication.