An apparent preferential antagonism by practolol of the positive inotropic responses of guinea-pig isolated atria to isoprenaline.

@article{Nicholson1980AnAP,
  title={An apparent preferential antagonism by practolol of the positive inotropic responses of guinea-pig isolated atria to isoprenaline.},
  author={Charles D. Nicholson and Kenneth J. Broadley},
  journal={Archives internationales de pharmacodynamie et de therapie},
  year={1980},
  volume={244 2},
  pages={270-80}
}
The positive inotropic response of guinea-pig isolated atria to isoprenaline was antagonized to a greater extent than the positive chronotropic response, when measured at 38 degrees C as the reduction of the responses to a single concentration of isoprenaline. This method avoided increasing the the concentration of agonist in the presence of practolol and any difference in the proportion metabolized affecting the blockade. This observation was substantiated from the vertical displacement of… CONTINUE READING