[Blocking effect of anisodamine on acetylcholine receptor channels]

Anisodamine, an analog of atropine, was isolated first in China. Patch-clamp technique was used to study the inhibitory effect of anisodamine (Ani) on acetylcholine receptor on the membrane of muscle innervated by neuron. Neural tube in embryo of Xenopus laevis were cultured. By whole-cell clamp and outside-out patch, we found that the inhibitory effect of Ani was obvious on both miniature end-plate currents (MEPC) and single channel. This effect was reversible and the minimal concentration for complete inhibition was 60 mumol.L-1, vs 1 and 0.5 mmol.L-1 for atropine and scopolamine, respectively. Our results indicate that Ani blocks both M-ACh and N-ACh receptors.