Rotenone interference with neuronal transmission in hippocampus

Abstract

Rotenone is a pesticide and insecticide, which causes behavioral, biochemical, and neuropathologic changes in rats that closely resembles PD symptoms in humans. It is known that this pesticide inhibits mitochondrial complex-I, which has an important role in cellular energy production. The object of the current research is to investigate the effect of rotenone on synaptic transmission between neurons in hippocampus, especially its effect on the glutamergic transmission. For this purpose, CA1 pyramidal neuronal response upon low frequency stimulation of Schaffer collateral (0.1 Hz) was recorded by patch clamp tight-seal whole cell recording technique from CA1 pyramidal neuron of rat hippocampus. Different rotenone concentrations were tested on glutamate current; it was observed that rotenone effect on the amplitude of glutamergic currents is dependent on its concentration. To eliminate the rotenone induced cytoplasmic second messenger system effect, ATP was excluded from intra-cellular solution in experiments. Thus, observed effects of rotenone on glutamergic currents occur via its direct effect on cell membrane receptors rather than rotenone-induced intracellular enzymatic or mitochondrial activities.|Keywords: Rotenone, Hippocampus, CA1 pyramidal neuron, Synaptic transmission, Glutamergic Currents, Patch Clamp Tight-Seal Whole Cell Recording Technique.