Huperzine-A is mainly an anticholinesterase, It DOES seem to bind within the NMDAr ion channel rather than as a competitive antagonist, or buggering around at polyamine/glycine sites. But I've tried it (at high end nootropic doses, without dissociative effects), as a nootropic, and I can more or less guarantee that the most pleasant effect of trying to take it to a dissociative recreational level would be SLUDGE, if not full blown nerve agent poisoning. A pukefest from multiple orifices one isn't even aware previously existed would be a definite extreme probability.
http://onlinelibrary.wiley.com/doi/...sCustomisedMessage=&userIsAuthenticated=false
DOI: 10.1002/jat.805
Journal of applied toxicology
The NMDA receptor ion channel: a site for binding of huperzine A.
Unless there are binding sites we know nothing of, then its within the channel/PCP site. Can anyone get the fulltext?
It seems to rule out glutamate1 and glutamate2 (low and high affinity glutamate sites), polyamine (what DOES the polyamine site do? control phosphorylation/dephosphorylation via protein kinases, and its not binding to glycine site either as I can see from the abstract.
I'd love to see the fulltext though, it would be interesting to try and develop a pharmacophore for this structural backbone that had less cholinesterase inhibitor activity and concentrated on finding psychoactive NMDAr antagonists.
I think the current compound, huperzine-A itself is a great nootropic, although galantamine, another anticholinesterase, although also an alpha7 NAChR agonist, providing an additional mode of nootropic action, increasing BDNF secretion amongst other things. Although I'll admit, BDNF, and Trk-b modulators of that kind are complex little fuckers at the best of times), but it IS a potent anticholinesterase, which are in effect, pharmaceutical nerve agents, and huperzine-A is active fully at 1-1.5-2mg at most, taking 2mg without building up a few hundred mikes a time is really likely to make you choke your GI tract up out through your eustachian tubes, its active in the microgram range, so I'd guess its actually MORE toxic, on a mcg/mg for mcg/mg basis than tabun and sarin. OD is treatable easily enough, but I've heard tales of heavy sweating, urination, lachrymation, keck-beshittance and some nightmarish sounding muscle spasms and SEVERE projectile vomiting+GI upset from large doses. Although how much will vary per person. I built up relatively fast to up to 5mg, and loved it, although still I will always like galantamine better