[Anti-cholinesterase activity of fordine]

The inhibitory effect of fordine on human true cholinesterase (ChE) was found to be 55386 times larger than on pseudo ChE in vitro. There was a marked difference in the inhibition of fordine on pseudo ChE of different species. The order of the decrease of potency of fordine on true ChE of different species was man, dog, rabbit, cat, rat and mouse. The order of the decrease of potency on pseudo ChE was rabbit, rat, dog, cat, mouse and man. In vivo, it was shown that ChE in blood and brain was strongly inhibited by fordine, and the duration of the inhibitory action was comparatively long. The ChE activity inhibited by fordine may recover spontaneously.