Nicotinic stimulant, DMPP(1,1-dimethyl-4-phenylpiperazinium iodide) on the isolated bronchial smooth muscle preparation of guinea-pig.

Contractile responses of the isolated bronchial preparation of guinea-pig to DMPP, a nicotinic stimulant, were inhibited by ganglion blockers but not influenced by atropine, suggesting that DMPP did not bring about a contribution by stimulation of cholinergic ganglion cells. The fact that tetrodotoxin did not influence the response to DMPP suggests that a possible site of action of DMPP is not on the nerve cells.