The opposed influences ofβ-adrenergic stimulation and adenosine on the frequency-force relationship of isolated left atria of guinea-pigs

@article{Hilgemann2005TheOI,
  title={The opposed influences of$\beta$-adrenergic stimulation and adenosine on the frequency-force relationship of isolated left atria of guinea-pigs},
  author={Donald W Hilgemann and Robert Englert and Hartwig Mensing},
  journal={Experientia},
  year={2005},
  volume={33},
  pages={1629-1631}
}
The normal frequency-force relationship of left guinea-pig atria can be largely suspended when strong β-adrenergic stimulation by orciprenaline is antagonized by the negative inotropic effect of adenosine, so that contraction amplitude is nearly equal at an intermediate level over a wide range of stimulation rates. Curves obtained with a new method for recording continuous frequency-force loops are presented. 

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