Toth_1987_Neurotoxicol_8_507

A preparation of rat brain synaptosomes, partially permeabilized by the cholesterol-specific detergent digitonin, was developed to study the effects of the heavy metals Pb+2 and Cd+2 and of other divalent cations on acetylcholine release from nerve terminals. Consistent with the cation specificities of the transmitter release process in intact nerve terminals, 100 microM free Ba+2, Sr+2 and Ca+2 each induced a release of acetylcholine (ACh) while Ni+2, Co+2 and Mn+2 did not. 100 microM Pb+2 and Cd+2 also induced a release of ACh from the permeabilized synaptosomes. This suggests that, similar to Ba+2 and Sr+2, both Pb+2 and Cd+2 may induce transmitter release through a direct action on the transmitter release apparatus.