Voltage-dependent modulation of the neuronal nicotinic acetylcholine receptor-channel by cartap

✍ Scribed by Nagata, Keiichi; Ikeda, Tomoko; Shono, Toshio

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 140 KB
• Volume: 55
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199904)55:4<452::aid-ps929>3.0.co;2-t

✦ Synopsis

Nicotinic acetylcholine receptor-channels (AChR) are believed to be the target site of cartap. In order to clarify the mechanisms of the cartap interaction with nicotinic AChRs, singlechannel patch clamp experiments were performed using rat clonal phaeochromocytoma (PC12) cells. Cartap increased the short closures occurring during single-channel openings induced by acetylcholine (ACh). Thus, when co-applied with acetylcholine, cartap markedly shortened the open time associated with bursts. These eþ ects were voltage-dependent, being more prominent at negative voltages. These results strongly suggest that cartap acts as an open channel blocker at the neuronal nicotinic AChR.