Benzodiazepines have been useful tools for investigating mechanisms underlying learning and memory. The present set of experiments investigates the role of hippocampal GABA[subscript A]/benzodiazepine receptors in memory consolidation using Pavlovian fear conditioning. Rats were prepared with cannulae aimed at the dorsal hippocampus and trained with a series of white noise--shock pairings. In the first experiment, animals received intrahippocampal infusion of midazolam or vehicle immediately or 3 h after training. Then, 24 h later, freezing to the training context and the white noise were measured independently. Results show infusion of midazolam immediately, but not 3 h, after training selectively attenuates contextual fear conditioning. In the second experiment, animals received intrahippocampal infusions of an antisense oligodeoxynucleotide (ODN) targeting the [alpha]5 subunit of the GABA[subscript A] receptor or a missense control for several days prior to training and testing. Immediately after training, animals received an infusion of either midazolam or vehicle. Western blots conducted after testing showed a significant decrease in [alpha]5-containing GABA[subscript A] receptor protein. This reduction did not alter the effectiveness of midazolam immediately after training at impairing context fear memory. Therefore, [alpha]5-containing GABA[subscript A] receptors may not contribute to the effects of midazolam on context fear conditioning when given immediately post-training. (Contains 3 figures.)