Glutamate metabotropic receptors modulate the expression of in vitro epileptiform activity in rat hippocampal slices

The effects of the mixed class I and II mGLUR agonist (+) 1S,3R-trans-amino-cyclopentane-1,3-dicarboxylic acid (ACPD) and antagonists (+) alpha-methyl-4-carboxyphenylglycine (MCPG) and L-2-amino-3-phosphonopropionic acid (L-AP3) on the basal neuronal excitability and on the expression of in vitro epileptiform activity produced by the convulsant drugs picrotoxin and penicillin were investigated in rat hippocampal slices. The duration of the CA1 epileptiform bursting produced by 0.05 mM picrotoxin or 1 mM penicillin or 0.075 mM ACPD was significantly (p<0.05) and dose-dependently decreased by 0.3-0.5 mM MCPG or L-AP3, but not by 0.05 mM ACPD. The data demonstrate an involvement of class I and II mGLURs in the basal neuronal excitability and in the expression of in vitro epileptiform activity produced by some convulsants.