Table 1.

Values used in an allosteric blocking model

AgonistsK1 (μm)K2 (μm)P1P2
GABA50500350
+Bicuculline50500350
+Gabazine50500350
Pentobarbital50005000100
+Bicuculline50005000100600
+Gabazine50005000100100
Alphaxalone2006
+Bicuculline20066
+Gabazine20066
BlockersL1 (μm)L2 (μm)Q
Bicuculline808060
Gabazine0.60.60.6
• Parameters are defined in Results and Figure 8. A dash indicates that the parameter was not used in a particular fit. It was assumed that GABA bound to two sites with different microscopic dissociation constants (K1, K2). In the cases of pentobarbital, bicuculline, and gabazine, the microscopic dissociation constants are assumed to be identical. For alphaxalone, only a single site was assumed to exist. The equilibrium constants for activation are shown with only agonist bound (P1), or in the cases of pentobarbital and alphaxalone for activation with both agonist and blocker bound (P2). The blocking allosteric constant is shown as Q.