Benzodiazepines modify evoked action potentials of the rat sciatic nerve in vitro

✍ Scribed by Piet Mantel; Johan van Hamme; Tom Piek; Remy S. Leeuwin

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 968 KB
• Volume: 22
• Category: Article
• ISSN: 0893-6609
• DOI: 10.1002/(sici)1520-6769(199805/06)22:3<163::aid-nrc5>3.0.co;2-t

✦ Synopsis

Diazepam, midazolam and clonazepam were examined at concentrations varying from 3.10m5 to 3.1W4 M. In the isolated rat sciatic nerve preparation all compounds produced significant time-and concentrationdependent inhibition of evoked action potentials. With increasing time intervals the response became increasingly concentration-dependent. Concentrations of 3.10e5 M of midazolam or clonazepam -and diazepam, at the time intervals up to 24 min, to a lesser extent -produced a slight increase of the amplitude. The time-response curves of diazepam tended to flatten between 24 and 60 min. Clonazepam, after eliciting intitial increase at 6.10s5 M, reduced the action potentials only in the range of l.lo-4 to 3.10-4 M. The latter reduction was time-dependent in a significant way at concentrations of 3.10m4 M. The Emax values of the benzodiazepines were increased progressively with the exposure time, i.e. that of diazepam > midazolam > clonazepam. It is concluded that, in the concentrations studied, benzodiazepines have direct time-dependent blocking actions on nerve conduction in isolated motor nerves -involving ion channel currentsthose of diazepam being the most potent.