Chronic flumazenil (Ro 15-1788) facilitates acquisition and retention of a swim-escape response in rats.
Since chronic flumazenil treatment was previously found to stimulate exploratory behavior in rodents, the aim of this study was to test the effect of chronic exposure to flumazenil on acquisition and retention of escape behavior. Adult rats were treated with flumazenil (Ro 15-1788; 4 mg/kg/day in drinking water) for 21 days (experiment 1) and for 17 days (experiment 2). In experiment 1 (a round water tank with one escape rope) conducted 24 h after drug/vehicle withdrawal, the time the animals needed to resolve a swim-escape task was significantly shorter in the drug group, compared to the controls. In the retention trial, 24 h later, the control group matched the performance of the drug group. In experiment 2, a water T-maze was used which was equipped with two ropes, one anchored to the bottom and the other unanchored and therefore was more difficult to climb. On day 14 of flumazenil/vehicle treatment, there were no differences between the groups in the time needed to escape from the maze. However, on day 15 and 16 of drug/vehicle treatment, the drug group made highly significant progress, while the control group showed no improvement of the escape behavior. The possible mechanisms of flumazenil-induced facilitation of escape behavior have been discussed.
Urbancic
M
M
Department of Pharmacology, University of Illinois, Chicago.
Gadek
M
M
Marczynski
T J
TJ
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D005442:Flumazenil / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012153:Retention, Psychology / Q000187:drug effects; D013550:Swimming; D013647:Task Performance and Analysis
D005442:Flumazenil