Caffeine-induced contractions in rabbit isolated renal artery are differentially inhibited by calcium antagonists.

  title={Caffeine-induced contractions in rabbit isolated renal artery are differentially inhibited by calcium antagonists.},
  author={Gareth W. John and E Fabr{\`e}gues and Mohamed Kamal and Roy Massingham},
  journal={European journal of pharmacology},
  volume={196 3},
Caffeine (1-60 mM) induced concentration-dependent, endothelium-independent phasic contractile responses in isolated rabbit renal artery ring preparations. For concentrations of caffeine over 2 mM, responses were mainly the result of intracellular calcium ion mobilization since they were relatively resistant to removal of calcium ions from the bathing medium. The L-type slow calcium channel blocker, nifedipine (10 microM), had no effect and high concentrations of verapamil and diltiazem (10-30… Expand
6 Citations
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