Gert Paschelke

Does the reversal of the anticonflict effect of phenobarbital by β-CCE and FG 7142 indicate benzodiazepine receptor-mediated anxiogenic properties?

In mice and rats, the high affinity ligand for brain benzodiazepine (BZ) receptors beta-CCE, and the more stable congener FG 7142, failed to exert anticonflict activity in conflict situations but instead reversed the anticonflict effect of lorazepam. In contrast to Ro 15-1788, beta-CCE and FG 7142 also antagonized the anticonflict effect of phenobarbital in rats. This effect suggests that beta-CCE and FG 7142 may produce anxiety by either inducing a conformational change in the BZ receptors which is directly opposite to that induced by the benzodiazepines, or binding to a particular subclass of BZ receptors.