In vivo interactions between the benzodiazepine antagonist Ro 15-1788 and the steroid anaesthetic althesin in rats.

Althesin and delta 16-alphaxalone have been used alone and in combination with the benzodiazepine antagonist Ro 15-1788 to investigate any protective effect these drugs might have against bicuculline-induced convulsions in rats. We found that Althesin provided good protection against bicuculline-induced convulsions which was enhanced when Ro 15-1788 was also present. delta 16-Alphaxalone lacks the anaesthetic properties of Althesin, but did have some activity in preventing bicuculline-induced convulsions, although it was less effective than Althesin. Its action was not enhanced by treatment with Ro 15-1788. Although we have no definitive explanation of these results, it is possible that when Ro 15-1788 is used clinically, it may interact with other drugs not related chemically to the benzodiazepines.