Increased seizure susceptibility following trimethyltin administration in rats

Acute treatment with trimethyltin (TMT) produces a multitude of behavioral effects including spontaneous convulsions in some animals. The present study used several different experimental seizure models to investigate seizure susceptibility in TMT-treated rats. Rats surgically implanted with electrodes in the amygdala and treated with TMT kindled more rapidly than saline-treated controls. Similarly, rats implanted with electrodes in the dorsal hippocampus kindled more rapidly than controls. Although TMT did not alter the properties of hippocampal afterdischarges, the threshold for production of after discharges was increased in both hippocampal and amygdaloid kindled rats, probably due to cell loss. TMT also increased the sensitivity of rats to pentylenetetrazol, thus suggesting that the increased seizure susceptibility was not limited to the limbic system.