Comparative studies on the anti-punishment effects of chlordiazepoxide, buspirone and ritanserin in the pigeon, Geller-Seifter and Vogel conflict procedures.

The studies presented here compared the responsiveness to clinically effective anxiolytics of two major conflict procedures in rat (i.e. the Geller-Seifter and Vogel procedures) and of the newly introduced pigeon conflict procedure. The compounds studied were the prototypical benzodiazepine chlordiazepoxide and the non-benzodiazepine anxiolytics buspirone and ritanserin. Chlordiazepoxide produced reliable anti-punishment effects in all three procedures, but only the pigeon conflict procedure also revealed statistically significant effects on punished responding with buspirone and ritanserin. The data thus constitute the first confirmation of findings from another laboratory that these two non-benzodiazepine compounds exert robust disinhibitory effects on punished behavior in the pigeon. Further, the quantification of drug effects on punished and on unpunished responding in the pigeon. Further, the allowed the effects of the three compounds to be differentiated. The pigeon conflict procedure may be unique among available animal models of anxiety in combining the following two features. Firstly, the procedure allows the behavioral response to be highly defined and permits the experimenter to control rigidly the stimulus events which act in a conflicting manner to increase and decrease response frequency. Secondly, [??084] behavior in this procedure is responsive to benzodiazepines, but also to anxiolytic drugs the effects of which are not mediated by benzodiazepine receptors. It is proposed that the pigeon conflict procedure be used in extensive parametric studies, in an effort to examine the independent variables which may perhaps explain the widely varying and often paradoxical effects that drugs can produce in available animal models of anxiety.