Mode of action of lindane, dieldrin and related insecticides in the central nervous system

A mode of action for lindane, dieldrin and related chlorinated hydrocarbon insecticides is proposed. The available evidence suggests that these insecticides act upon neurons in a global manner. Their primary target is the synapse, and they act there to intensify synaptic activity, primarily by enhancing transmitter release from the presynaptic terminal. All neurons appear to be affected. There is no apparent predilection for excitatory or inhibitory systems in the nervous system nor is there evidence for a specific action upon a single neurotransmitter or neurotransmitter system. It is proposed that the modifications that occur in behavior are based upon this same mode of action. A simplified model of brain plasticity, the kindled seizure model, is described as a potential tool for further investigation.