Reference

Effects of huperzine A and B on skeletal muscle and electroencephalogram

Effects of huperzine A and B on skeletal muscle and electroencephalogram. Yan, Xiaofang; Lu, Weihua; Lou, Weijian; Tang, Xican (Shanghai Inst. Mater. Med., Chin. Acad. Sci., Shanghai 200031, Peop. Rep. China). Zhongguo Yaoli Xuebao, 8(2), 117-23 (Chinese) 1987. CODEN: CYLPDN. ISSN: 0253-9756. 102518-79-6 and 103548-82-9 are also in the experiment. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) The effect of huperzine A [102518-79-6] and huperzine B [103548-82-9] on skeletal muscle and EEG was compared with that of clin. used cholinesterase inhibitors in mice, rats, and rabbits, using nerve-muscle prepns. in vitro and in situ. Results indicated that huperzine A and B may have therapeutic value for some diseases with functional deficiency of peripheral and central cholinergic systems; after i.v. administration, the order of potentiation of muscle contraction and anticurare activity was neostigmine > huperzine A > physostigmine > huperzine B > galanthamine; however, huperzine A and B caused less salivation than did neostigmine and physostigmine. .

Structure of acetylcholinesterase complexed with the nootropic alkaloid, (-)-huperzine A

Structure of acetylcholinesterase complexed with the nootropic alkaloid, (-)-huperzine A. Raves, Mia L.; Harel, Michal; Pang, Yuan-Ping; Silman, Israel; Kozikowski, Alan P.; Sussman, Joel L. (Dep. Structural Biol., Weizmann Inst. Sci., Rehovot 76100, Israel). Nature Structural Biology, 4(1), 57-63 (English) 1997 Nature Publishing Co. CODEN: NSBIEW. ISSN: 1072-8368. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) Section cross-reference(s): 75 (-)-Huperzine A (HupA) is found in an ext. from a club moss that has been used for centuries in Chinese folk medicine. Its action has been attributed to its ability to strongly inhibit acetylcholinesterase (AChE). The crystal structure of the complex of AChE with optically pure HupA at 2.5 ? resoln. shows an unexpected orientation for the inhibitor with surprisingly few strong direct interactions with protein residues to explain its high affinity. This structure is compared to the native structure of AChE devoid of any inhibitor as detd. to the same resoln. An anal. 9000-81-1 and 102518-79-6 are just another two chemicals used in this study. of the affinities of structural analogs of HupA, correlated with their interactions with the protein, shows the importance of individual hydrophobic interactions between HupA and arom. residues in the active-site gorge of AChE. .