Are "peripheral-type" binding sites for benzodiazepines in brain related to the convulsant actions of Ro 5-4864?

Previous studies have shown that Ro 5-4864 is a potent convulsant. Investigation of a series of compounds structurally related to Ro-4864 revealed a good correlation (r = .93, p less than 0.01) between their potencies as convulsants and their abilities to displace [35S]t-butylbicyclophosphorothionate from sites associated with the chloride ionophore. In contrast, there appears to be no direct relationship between the convulsant potencies of these compounds and their affinities for "peripheral-type" binding sites for benzodiazepines. These data suggest that "peripheral-type" binding sites for benzodiazepines are not directly involved in the convulsant actions of Ro 5-4864 and related compounds nonetheless, several lines of evidence suggest that "peripheral-type" binding sites for benzodiazepines may be indirectly involved in the convulsant properties of Ro 5-4864.