Blockade of metabotropic glutamate receptors prevents long-term memory consolidation.

Metabotropic glutamate receptor activation has been shown to be essential for establishment of long-term potentiation, a phenomenon increasingly thought to be associated with the laying down of permanent memory. However, these receptors may also play a part in the initiation of protein kinase C activity, which has been demonstrated to be involved in prelong-term memory processes. Blockade of the metabotropic glutamate receptors by the specific antagonist, (RS)-alpha-Methyl-4-carboxyphenylglycine (500 microM) is shown to induce amnesia during a long-term memory stage in day-old chicks trained on a passive avoidance task, and to have no effect on prelong-term stages. The results suggest a specific role for these receptors in a possibly LTP associated mechanism of memory processing.