TABLE 3

Propofol and pentobarbital concentration-response data for α1β3 receptors

The concentration-response data from each cell were fitted with eq. 1 (Materials and Methods). The table shows propofol, pentobarbital, and GABA EC50 values (mean ± S.E.M.) from at least four cells under each condition. Relative currents were estimated by comparing responses to saturating propofol, pentobarbital, and GABA in the same cell. Saturating GABA produces responses with the Po of near 1 because coapplication of 1 µM alphaxalone did not modify peak responses to saturating GABA (data not shown).

ReceptorPropofol EC50Pentobarbital EC50GABA EC50Ipropofol/IGABAIpentobarbital/IGABA
µM%
α1β3 wild type13 ± 287 ± 131.4 ± 0.137 ± 521 ± 3
α1(I271W)β35 ± 168 ± 50.6 ± 0.189 ± 391 ± 1
α1(I271W)β3(T266W)9 ± 1113 ± 303.3 ± 0.776 ± 387 ± 3
α1β3(T266W)4 ± 1166 ± 420.2 ± 0.0474 ± 193 ± 4