Studies on some pharmacological activities of 7-nitro-2-amino-5-phenyl-3H-1,5-benzodiazepine (CP 1414 S) in the rat. A comparison with diazepam.

Brain distribution and various pharmacological effects of 7-nitro-2-amino-5-phenyl-1,5-benzodiazepine (CP 1414 S) and diazepam were studied in rats. Injected at 10 mg/kg i.p., the compounds reached brain peak concentrations 15 min after administration and showed an apparent half-life of about 50 min. CP 1414 S was about ten times less potent than diazepam in protecting rats from pentetrazole convulsions, increasing punished responses in a "conflict" test and disrupting rotarod performance. At the lowest doses effective in these tests diazepam, but not CP 1414 S, caused significant reduction of spontaneous locomotor activity in rats. On the basis of the test selected, it is concluded that CP 1414 S causes effects similar to those shown by diazepam in the same conditions, although with less potency. It causes less depression of motor behaviour than diazepam, at least at the lowest doses and in rats.