BEHAVIORAL-EFFECTS IN MICE OF SUBCHRONIC CHLORDIAZEPOXIDE, MAPROTILINE AND FLUVOXAMINE .2. THE ELEVATED PLUS-MAZE

In view of apparent commonalities in the aetiology, symptomatology, an d pharmacotherapy of anxiety and depressive disorders, the present stu dy compares the effects of the benzodiazepine, chlordiazepoxide (1.0-8 .0 mg/kg), the selective noradrenaline (NA) reuptake inhibitor, maprot iline (0.5-10.0 mg/kg), and the serotonin (5-HT)-selective reuptake in hibitor, fluvoxamine (2.0-8.0 mg/kg), on the behaviour of mice in the elevated plus-maze test of anxiety. To more accurately reflect the cli nical situation, subjects were treated dairy for 21 days prior to test ing, and comprehensive behavioural profiles were obtained through the application of an ethological scoring technique. Results show that sub chronic treatment with chlordiazepoxide produced clear anxiolytic-like effects at the highest dose tested, coupled with an inhibition of ris k assessment over the entire dose range. With the exception of risk as sessment measures, anxiolytic-like effects were also seen with a low d ose (0.5 mg/kg) of maprotiline; these effects were lost at higher dose s. In contrast to these data, fluvoxamine produced minimal behavioural change under present test conditions. Findings are discussed in relat ion to the relative efficacy of selective monoamine reuptake inhibitor s in the treatment of anxiety disorders, and the nature of anxiety evo ked in mice by exposure to the elevated plus-maze. (C) 1997 Elsevier S cience Inc.