Fig. 4.

N-(5-chloro-2,4-dimethoxyphenyl)-N′-(5-methyl-3-isoxazolyl)-urea [PNU-120596 (PNU)] revealed cells expressing α7 nicotinic acetylcholine receptors. Functional expression of α7 nicotinic acetylcholine receptors was found in a subset of cells from subclass 1 of Fig. 1 (A), a subset of acetylcholine-responsive cells (B), and a subset of cells that did not respond to other agonists tested (C). D: representative traces from cells that did not respond to acetylcholine under any condition tested in this experiment.