TY - JOUR T1 - The effect of the cytochrome P-450 suicide inactivator, 1-aminobenzotriazole, on the in vivo metabolism and pharmacologic activity of flurazepam. JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 190 LP - 196 VL - 18 IS - 2 AU - S Capello AU - L Henderson AU - F DeGrazia AU - D Liberato AU - W Garland AU - C Town Y1 - 1990/03/01 UR - http://dmd.aspetjournals.org/content/18/2/190.abstract N2 - Flurazepam (F) is an extensively prescribed hypnotic (Dalmane) whose in vivo activity has been suggested to be due to its primary metabolites, hydroxyethyl flurazepam (HEF) and N-desalkylflurazepam (DAF). In order to determine the intrinsic pharmacologic activity of F, mice were administered various doses of the cytochrome P-450 suicide inactivator, 1-aminobenzotriazole (ABT), 1 hr before the ip administration of 1 mg/kg 14C-F. One hr after 14C-F, 70 mg/kg pentylenetetrazole was administered iv and the mice were observed for convulsions. F alone offered no protection from convulsion (mean brain concentrations were 3.9, 32, and 11 ng/g for F, DAF, and HEF, respectively). F with 25 mg/kg ABT also offered no protection despite a 6-fold increase in brain concentrations of F. F with 100 mg/kg ABT offered a 57% protection from convulsions (mean brain concentrations were 99, 62, and 41 ng/g for F, DAF, and HEF, respectively). One mg/kg F with 400 mg/kg ABT offered 100% protection from convulsions (brain concentrations were 190, 47, and 18 ng/g for F, DAF, and HEF, respectively). These data indicate that F has intrinsic pharmacologic activity which must be considered when evaluating the pharmacodynamics of F. ER -