Abstract
The benzodiazepine Ro 5-4864 (60 mg/kg) produced convulsions in mice that could be antagonised either by diazepam (2–4 mg/kg) or by Ro 15-1788 (10–20 mg/kg). In mice and rats subconvulsant doses of Ro 5-4864 were proconvulsant when combined with subconvulsant doses of picrotoxin or pentylenetetrazole. Ro 15-1788 antagonised the tonic convulsions triggered by the drug combinations when it was given at the same time as Ro 5-4864; this antagonism was not observed when the drugs were injected at different times. In contrast to a previous report, we could find no evidence that Ro 5-4864 antagonised seizures induced by electroshock. Using two different ligand-binding techniques, no evidence was seen for the existence in rat brain of the previously reported “micromolar” benzodiazepine receptor, a suggested site of action of Ro 5-4864.
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File, S.E., Green, A.R., Nutt, D.J. et al. On the convulsant action of Ro 5-4864 and the existence of a micromolar benzodiazepine binding site in rat brain. Psychopharmacology 82, 199–202 (1984). https://doi.org/10.1007/BF00427773
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DOI: https://doi.org/10.1007/BF00427773