The anxiolytic effects of intra-hippocampal midazolam are antagonized by intra-septal L-glutamate.
According to Gray [The Neuropsychology of Anxiety: An Enquiry into the Functions of the Septo-hippocampal System, Oxford University Press, New York, 1982], the hippocampus and the septum act in concert to control anxiety. We found that micro-infusion of midazolam into the dorsal hippocampus increased rats' open-arm exploration in the elevated plus-maze. Co-infusion of L-glutamate into the septum suppressed this anxiolytic effect. However, intra-hippocampal midazolam failed to alter rats' burying behavior in the shock-probe test. These findings suggest that the hippocampus and septum work together to regulate rats' behaviors in some (plus-maze) but not all (burying) animal tests of anxiety.
Menard
J
J
Douglas Hospital Research Center, 6875 LaSalle Boulevard, H4H 1R3, Montreal, PQ, Canada.
Treit
D
D
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001007:Anxiety / Q000188:drug therapy* / Q000378:metabolism; D001522:Behavior, Animal / Q000187:drug effects; D018698:Glutamic Acid / Q000494:pharmacology*; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008845:Microinjections; D008874:Midazolam / Q000494:pharmacology*; D009434:Neural Pathways; D051381:Rats; D017207:Rats, Sprague-Dawley; D020665:Septum of Brain / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
D014151:Anti-Anxiety Agents; D018698:Glutamic Acid; D008874:Midazolam