Ethylcholine mustard aziridinium ion (AF64A) impairs cholinergic neuromuscular transmission in the guinea-pig ileum and urinary bladder, and cholinergic neuromodulation in the enteric nervous system of the guinea-pig distal colon.

AF64A was examined for its ability to impair cholinergic neurotransmission in the autonomic nervous system. In the guinea-pig ileum AF64A impaired cholinergic neuromuscular transmission. In the guinea-pig urinary bladder AF64A selectivity impaired the cholinergic but not the purinergic component of neuromuscular transmission. In the guinea-pig colon circular muscle AF64A impaired cholinergic neuromodulation of the inhibitory transmission but not the inhibitory transmission itself. The nature of impairment of cholinergic transmission by AF64A is discussed.