Is the muscle relaxant effect of diazepam in spastic mutant rats mediated through GABA-independent benzodiazepine receptors?
Diazepam (0.4-0.8 mg/kg i.p.) reduced the spontaneous activity in the electromyogram (EMG) recorded from the gastrocnemius-soleus muscle of spastic mutant Han--Wistar rats in a dose-dependent manner. The depressant effect of diazepam (0.8 mg/kg) on the EMG activity was antagonized by Ro 15-1788 (5 mg/kg i.p.) and by picrotoxin (2 mg/kg i.p.), but not by bicuculline (2 mg/kg i.p.). These results suggest that diazepam depresses EMG activity of mutant rats by mechanisms related to the interaction of the drug with GABA-independent benzodiazepine receptors.
D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology; D001640:Bicuculline / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology*; D004576:Electromyography; D005260:Female; D005442:Flumazenil; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D010852:Picrotoxin / Q000494:pharmacology; D051381:Rats; D011922:Rats, Mutant Strains; D011956:Receptors, Cell Surface / Q000187:drug effects*; D011963:Receptors, GABA-A
D001570:Benzodiazepinones; D001640:Bicuculline; D003975:Diazepam; D005442:Flumazenil; D010852:Picrotoxin; D011956:Receptors, Cell Surface; D011963:Receptors, GABA-A