GlyR agonist efficacy is lower in humanα1 GlyR than in zebrafishα1 GlyREM, a channel from which the ICD has been excised.A and B, upper panels, whole cell current responses to the application of glycine, β-alanine, taurine, and GABA by U-tube to HEK 293 cells expressing human α1 GlyR (A) or zebrafish α1 GlyREM (B). A and B, lower panels, averaged concentration-response curves of glycine (black), β-alanine (blue), taurine (red), and GABA (green) in human α1 GlyR (A) and zebrafish α1 GlyREM (B). Each dose-response curve is constructed by pooling individual concentration-response curves obtained in different cells (n = 4 –14, see Table 1). Error bars represent S.E. Responses were normalized to the response to 10 mm glycine in each cell.
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