The adenosine binding enhancer, PD 81,723, inhibits epileptiform bursting in the hippocampal brain slice.

The effects of adenosine and the adenosine binding enhancer, PD 81,723, on low magnesium-induced bursting in the in vitro hippocampal slice were examined. Extracellular recordings were obtained from the CA3 pyramidal cell layer while electrically stimulating in the stratum radiatum under low magnesium perfusion. Adenosine (6-100 microM) reduced the duration of epileptiform bursting in a dose-related manner, which was reversible upon washout of adenosine. Application of PD 81,723 (50-100 microM) also resulted in a dose-dependent reduction in the duration of the triggered burst, which was irreversible. These results demonstrate anticonvulsant activity of adenosine and the adenosine binding enhancer, PD 81,723, in the low magnesium model of epilepsy.