Enhancement of performance by methyl beta-carboline-3-carboxylate, in learning and memory tasks.

Benzodiazepines are known to induce a profound anterograde amnesia in man. In this report, it is shown that methyl beta-carboline-3-carboxylate (beta-CCM), an inverse agonist of the benzodiazepine receptor, has the opposite effect; it enhances performance in learning and memory tasks. Three different learning models were used: habituation to a new environment and passive avoidance in mice and imprinting in chicks. The opposite effects of both beta-CCM and the benzodiazepine diazepam were blocked by administration of the benzodiazepine receptor antagonist Ro 15-1788, providing evidence that the benzodiazepine receptor is involved in these effects.