Pharmacological Effects of Imidacloprid and Its Related Compounds on the Nicotinic Acetylcholine Receptor with Its Ion Channel from the Torpedo Electric Organ

Abstract

Effect of various ligands which include imidacloprid related compounds, on the binding of [3H]phencyclidine (PCP) known as a probe for the allosteric site located in the receptor's ion channel and [3H]a-bungarotoxin (a-BGT) known as a probe for the acetylcholine (ACh) recognition site of the nicotinic acetylcholine receptor with its ion channel from the Torpedo electric organ, was examined. Nicotine and anabasine showed a strong agonistic action like carbachol and cytisine, whereas imidacloprid, 6-C1-PMNI, acetamiprid, NMTHT, nitenpyram and MTENI were weakly agonistic. NMTHT, nitenpyram and MTENI were also noncompetitive blockers like coniine, DMPP, nereistoxin and d-tubocurarine which interacted with both the ACh recognition site and the allosteric site. PCP, TCP, ketamine, chlorpromazine and mecamylamine were noncompetitive blockers; also lobeline and trimethaphan were found to be noncompetitive blockers as against text books. © 1995, Pesticide Science Society of Japan. All rights reserved.