Effects of chlordiazepoxide, buspirone and the 5-HT3 receptor antagonist, BRL 46470, on the behaviour of oestrous and dioestrous female mice when encountering male partners.
Ethological procedures were employed to examine the differences in behaviour between oestrous and dioestrous control mice, and to investigate the changes to behavioural responsiveness in oestrous and dioestrous mice induced by treatment with the anxiolytic compounds, chlordiazepoxide (CDP, 21.5 mg/l), buspirone (12.8 mg/l) and the 5-HT3 receptor antagonist, BRL 46470 (40 micrograms/l). Compounds were given in drinking fluid for 6-8 days prior to behavioural observations (average daily intake: CDP--5 mg/kg; buspirone--2.5 mg/kg; BRL 46470--10 micrograms/kg). Behaviour of the females was examined in the "approach-avoidance" situation of 5 min encounters with an unfamiliar male in a neutral cage. Oestrous controls spent more time in social investigation, sniffing of the substrate and scanning than dioestrous controls and spent less time in digging and exploration. Each of the anxiolytic compounds, CDP, buspirone and BRL 46470, significantly raised the duration of social investigation both in oestrous and dioestrous females. Each of these compounds also increased the duration of "digging" by oestrous females, and duration of the social element "investigate" in dioestrous females. Effects on the occurrence of other individual elements within each behavioural category depended on the anxiolytic compound administered and the stage of the ovarian cycle at the time of testing. There were few significant differences between the behaviour of the male partners in each group. It is concluded that in this paradigm both oestrous and dioestrous females are sensitive to the enhancement of social investigation by anxiolytic compounds and that the use of female mice in this test situation may provide a potentially useful method in drug screening.
Gao
B
B
Department of Biological Sciences, Glasgow Caledonian University, Scotland.
Cutler
M G
MG
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002065:Buspirone / Q000494:pharmacology; D002707:Chlordiazepoxide / Q000494:pharmacology; D004031:Diestrus / Q000502:physiology*; D004971:Estrus / Q000502:physiology*; D005260:Female; D007211:Indoles / Q000494:pharmacology; D008297:Male; D051379:Mice; D012702:Serotonin Antagonists; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D012919:Social Behavior
D014151:Anti-Anxiety Agents; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D007211:Indoles; D012702:Serotonin Antagonists; C075685:BRL 46470; D002707:Chlordiazepoxide; D002065:Buspirone