Inhibitory effect on gastric motility of chloroquine and mepacrine

Measured on isolated rat-stomach fundus strips, the isolated cervical sympathetic trunk, and on the superior cervical ganglion, chloroquine and mepacrine have parasympatholytic, spasmolytic, ganglionic blocking and local anaesthetic effects. On rising the doses these manifest themselves in a given sequence. On the basis of this fact it is concluded that the inhibition of gastric motility by chloroquine and mepacrine in the rat, is based on the parasympatholytic property of the drugs in question.