Pharmacokinetics of [~(125)I]Huwentoxin-1 after epidural and intravenous administration to rhesus monkeys / 中国药理学通报

ABSTRACT

96% and with the same bio-activity as unlabeled Huwen toxin-1; Radioactivity detected in epidural space was 38% of injected radioacti vity at 10 min after epidural injection, which demonstrated successful administr ation into epidural space; The maximum serum concentration after epidural or iv administration of [ 125 I]labeled Huwentoxin-1 were determined to be (0 70?0 04) MBq?L -1 and (4 98?0 58) MBq?L -1 , respectively, a t the maximum serum concentration times of 30 min and 2 min. Terminal T 1/2 after epidural or iv administration were (10 36?0 27) h or (11 03?1 16) h, respectively. Cls was (1 29?0 07) L?h -1 ?kg -1 or (1 25? 0 23) L?h -1 ?kg -1 , respectively. Bioavailability after epidural a dministration was(95?5)%. CONCLUSION Concentration-time cur ves of [ 125 I] labeled Huwentoxin-1 after two routes were different. The degradation profiles after epidural and iv injection supported the using of HWTX-1 as analgesic by epidural administration.