Relations between open-field- elevated plus-maze- and emergence tests in C57BL and 6J and BALB and c mice injected with GABA- and 5HT-anxiolytic agents-

Authors
R. Lalonde, C. Strazielle.

Lab
Centre Hospitalier de l'université de Montréal/St-Luc, Unité de Recherche en Sciences Neurologiques, Montréal, Québec, Canada.

Journal
Fundamental and clinical pharmacology

Abstract
Two 5HT(1A) receptor agonists and chlordiazepoxide were examined in open-field, elevated plus maze, and emergence tests. At doses with no effect in the open-field, chlordiazepoxide increased open and open/total arm visits as well as open arm duration in the elevated plus maze, whereas 5HT(1A) receptor agonists showed an anxiolytic response on a single measure. The anxiolytic action of chlordiazepoxide was limited to the less active BALB/c strain. Unlike the 5HT(1A) receptor agonists, chlordiazepoxide was also anxiolytic in the emergence test, once again only in BALB/c and not C57BL/6J mice. Significant correlations were found between emergence latencies and specific indicators of anxiety in the elevated plus-maze in chlordiazepoxide-treated but not in mice treated with buspirone and 8-OH-DPAT. These results indicate that elevated plus-maze and emergence tests depend on benzodiazepine receptors. In contrast, 5HT(1A) receptor agonists were ineffective in the emergence test and no correlation was found between emergence latencies and specific indicators of anxiety in the elevated plus-maze. Though superficially similar, the emergence test seems to tap into a partially separate facet of anxiety.

BIOSEB Instruments Used:
Infrared Actimeter (LE8815)