TABLE 3 

Stimulant and blocking effects of partial agonists measured in piglet and human atrial myocardium

Values are mean ± S.E.

AgonistPigletHuman
Right AtriumLeft AtriumRight Atrium
ChronotropicInotropicInotropic
Prucalopriden = 5n = 4n = 4
    Stimulation potency (−log EC50, M)7.35 ± 0.25a7.17 ± 0.07a7.09 ± 0.12
    Intrinsic activityb0.72 ± 0.11a 0.65 ± 0.05a0.51 ± 0.09
    Blocking potency (−log Kp, M)7.09 ± 0.21a 7.27 ± 0.33
Cisapriden = 4n = 4n = 5
    Stimulation potency (−log EC50, M)6.44 ± 0.08cND6.44 ± 0.14
    Intrinsic activityb0.43 ± 0.06c0.09 ± 0.020.27 ± 0.07
    Blocking potency (−log Kp, M)7.03 ± 0.226.15 ± 0.31
  • EC50, half maximal effective concentration; Kp, dissociation equilibrium constant; ND, not determined (effects were too small).

  • a Data from Kaumann; personal communication; 12 June 2000, Cambridge, UK.

  • b Intrinsic activity measured with respect to 600 μM 5-HT.

  • c Data previously published (Kaumann et al., 1990).