THE NEUROANATOMICAL SPECIFICITY OF THE ANXIOLYTIC EFFECTS OF INTRA-SEPTAL INFUSIONS OF MIDAZOLAM (VOL 710, PG 161, 1996)

Microinfusions of the benzodiazepine anxiolytic midazolam into the lat eral but not the medial septum suppressed fear reactions in two tests of rat 'anxiety'. Midazolam infusions into the lateral septal nuclei i ncreased open-arm exploration in the elevated plus-maze test, and bloc ked burying behavior in the shock-probe test, whereas midazolam infusi ons into the medial septum produced neither of these anxiolytic effect s. The anxiolytic effects of midazolam in the lateral septum were part ially blocked by pre-infusion of the benzodiazepine receptor antagonis t Ro 15-1788, which had no intrinsic effects by itself. These results suggest that the anxiolytic effects of intra-septal midazolam occur, a t least in part, at GABA(A)-benzodiazepine receptor sites located in t he lateral septal nuclei.