Table 8

Comparison of antagonist KB values for inhibition of H2-receptor-stimulated adenylyl cyclase activity in membranes and cyclic AMP accumulation in intact cellular systems

AntagonistAntagonist KB value (μM)Binding studies (Ki, μM)
Slices8-aDissociated cells8-bHomogenates8-c,8-d,8-eKrebs bufferTris buffer
Cimetidine0.60.50.9
Metiamide0.8n.d.1.0
Tiotidinen.d.0.030.030.020.007
Cyproheptadine5.7n.d.0.04
Mianserin10.02.80.071.010.20
Imipramine>103.30.2
Amitriptyline3.51.90.050.090.09
Chlorpromazine5.93.00.04
Haloperidol>10290.081.610.42
  • Measurements were made of H2-mediated adenylyl cyclase activity in homogenates of guinea pig hippocampus, impromidine-stimulated cyclic AMP accumulation in guinea pig hippocampal slices, and of H2-mediated cyclic AMP accumulation in dissociated hippocampal tissue. n.d., not determined.

  • 8-a Tuong et al. (1980)

  • 8-b Kamba et al. (1983)

  • 8-c Green et al. (1977)

  • 8-d Kanof and Greengard (1978)

  • 8-e Kanof and Greengard (1979a,b)

  • 8-f Traiffort et al. (1991)