Nereistoxin (NTX)

Nereistoxin (NTX; 4-N,N-dimethylamino-1,2-dithiolane) is previously reported to block both muscle and neuronal nicotinic acetylcholine receptors, and reversibly inhibit radioligand binding to Torpedo nicotinic receptors.

NTX blocked retinal responses to the nicotinic agonist dimethylphenylpiperazinium (300 microM, 2 sec) with an IC50 of 3.5 microM. NTX inhibition was selective for nicotinic receptors, long lasting and not reversible upon washing. The nonselective oxidizing compound dithiobis(nitrobenzoic acid) (1 mM) transiently and repetitively reversed NTX (100 microM) inhibition (85% recovery). After application of the alkylating agent bromoacetylcholine (2 or 100 microM, with 2 microM neostigmine), dithiobis(nitrobenzoic acid) could no longer restore nicotinic function.