The fifth subunit of the (α4β2) β2 nicotinic ACh receptor modulates maximal ACh responses.

Background And Purpose: The fifth subunit in the (α4β2) α4 nicotinic ACh receptor (nAChR) plays a determining role in the pharmacology of this nAChR type. Here, we have examined the role of the fifth subunit in the ACh responses of the (α4β2) β2 nAChR type.

Experimental Approach: The role of the fifth subunit in receptor function was explored using two-electrode voltage clamp electrophysiology, along with subunit-targeted mutagenesis and the substituted cysteine scanning method applied to fully linked (α4β2) β2 receptors.