Biphenylacetic acid enhances the antagonistic action of fluoroquinolones on the GABA(A)-mediated responses of the isolated guinea-pig ileum.

  title={Biphenylacetic acid enhances the antagonistic action of fluoroquinolones on the GABA(A)-mediated responses of the isolated guinea-pig ileum.},
  author={Maria Koutsoviti-Papadopoulou and Efstathios Nikolaidis and Georgios Kounenis},
  journal={Pharmacological research},
  volume={44 3},
This paper examines the effect of biphenylacetic acid on the antagonistic action of norfloxacin and enoxacin on the GABA(A)-mediated responses of the isolated guinea-pig ileum. GABA produced transient contractions followed by relaxation. The contractile effect of exogenously applied GABA was concentration-dependent with EC(50)= 9.8 x 10(-6) M. This contractile effect was not significantly modified by biphenylacetic acid, and the EC(50) value for GABA in the presence of 10(-5) M biphenylacetic… Expand
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