Behavioral and neurochemical studies on the anticonflict actions of buspirone

A series of behavioral and neurochemical studies were performed in order to determine if buspirone (or an active metabolite of this compound) could perturb a component of the γ‐aminobutyric (GABA)‐benzodiazepine receptor‐chloride ionophore complex. In confirmation of previous findings, buspirone was shown to have anticonflict actions in both the rat and monkey. However, in these tests, buspirone was not as efficacious as benzodiazepines in producing an anticonflict action. The benzodiazepine receptor antagonists CGS 8216 and Ro 15–1788 did not reverse the anticonflict actions of buspirone. Small but statistically significant increases in the binding of [³H]diazepam to brain were observed in vivo after doses of buspirone which are active in the “thirsty rat conflict” test. However, a similar change was not observed in the ex vivo binding of [³H]flunitrazepam. These observations suggest that a metabolite of buspirone may perturb some component of the GABA‐benzodiazepine receptor‐chloride ionophore complex in an indirect fashion. Further work is necessary to determine whether a causal relationship exists between the changes in [³H]diazepam binding observed in vivo and the anticonflict actions of buspirone.