Representative current traces for positive allosteric modulation of glycine induced currents by 4-chloropropofol at WT and mutated α
-glycine receptors. Traces elicited by a 2 s co-application of a sub-saturating glycine solution (EC20 = 10 μM WT, 30 μM S267I, 10 mM R271Q, 30 mM R271L and 100 μM R271K) and 4-chloropropofol. Respective upper traces show the maximal current elicited by a 1 mM (WT and S267I), 300 mM (R271Q and R271L) and 10 mM (R271K) respectively, glycine control solution. 4-chloropropofol increased the amplitude of the response evoked by glycine (second trace from top) in a concentration dependent manner (third and following traces from top).