ANI inactivation: unconditioned anxiolytic effects of anisomycin in the ventral hippocampus.
Although hippocampal function is typically described in terms of memory, recent evidence suggests a differentiation along its dorsal/ventral axis, with dorsal regions serving memory and ventral regions serving emotion. While long-term memory is thought to be dependent on de novo protein synthesis because it is blocked by translational inhibitors such as anisomycin (ANI), online (moment-to-moment) functions of the hippocampus (such as unconditioned emotional responding) should not be sensitive to such manipulations since they are unlikely to involve neuroplasticity. However, ANI has recently been shown to suppress neural activity which suggests (1) that protein synthesis is critical for neural function and (2) that paradigms using ANI are confounded by its inactivating effects. We tested this idea using a neurobehavioral assay which compared the influence of intrahippocampal infusions of ANI at dorsal and ventral sites on unconditioned emotional behavior of rats. We show that ANI infusions in ventral, but not dorsal, hippocampus produced a suppression of anxiety-related responses in two well-established rodent tests: the elevated plus maze and shock-probe burying tests. These results are similar to those previously observed when ventral hippocampal activity is directly suppressed (e.g., by using sodium channel blockers). The present study offers compelling behavioral evidence for the proposal that ANI adversely affects ongoing neural function and therefore its influence is not simply limited to impairing the consolidation of long-term memories
['Greenberg|Anastasia|A|', 'Ward-Flanagan|Rachel|R|', 'Dickson|Clayton T|CT|', 'Treit|Dallas|D|']
D000818:Animals D000841:Anisomycin D014151:Anti-Anxiety Agents D001007:Anxiety D002408:Catheters, Indwelling D004597:Electroshock D005106:Exploratory Behavior D006624:Hippocampus D008297:Male D009483:Neuropsychological Tests D010784:Photomicrography D011500:Protein Synthesis Inhibitors D017207:Rats, Sprague-Dawley
elevated plus maze anxiety dorsal hippocampus protein synthesis inhibition shock-probe test