Systemic administration of the potential countermeasure huperzine reversibly inhibits central and peripheral acetylcholinesterase activity without adverse cognitive-behavioral effects.
Huperzine A is potentially superior to pyridostigmine bromide as a pretreatment for nerve agent intoxication because it inhibits acetylcholinesterase both peripherally and centrally, unlike pyridostigmine, which acts only peripherally. Using rhesus monkeys, we evaluated the time course of acetylcholinesterase and butyrylcholinesterase inhibition following four different doses of -(-)huperzine A: 5, 10, 20, and 40 microg/kg. Acetylcholinesterase inhibition peaked 30 min after intramuscular injection and varied dose dependently, ranging from about 30% to 75%. Subsequently, cognitive-behavioral functioning was also evaluated at each dose of huperzine A using a six-item serial-probe recognition task that assessed attention, motivation, and working memory. Huperzine did not impair performance, but physostigmine did. The results demonstrate that huperzine A can selectively and reversibly inhibit acetylcholinesterase without cognitive-behavioral side effects, thus warranting further study.
Myers
Todd M
TM
United States Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010, USA. todd.myers2@us.army.mil
Sun
Wei
W
Saxena
Ashima
A
Doctor
Bhupendra P
BP
Bonvillain
Andrew J
AJ
Clark
Matthew G
MG
D000110:Acetylcholinesterase / Q000187:drug effects*; D000470:Alkaloids; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology; D003071:Cognition / Q000187:drug effects*; D008253:Macaca mulatta; D012717:Sesquiterpenes / Q000008:administration & dosage* / Q000494:pharmacology
D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D012717:Sesquiterpenes; C050426:huperzine A; D000110:Acetylcholinesterase