• Corpus ID: 24450689

Role of receptor reserve in the inhibition of alpha-1 adrenoceptor-mediated pressor responses by calcium antagonists in the pithed rat.

  title={Role of receptor reserve in the inhibition of alpha-1 adrenoceptor-mediated pressor responses by calcium antagonists in the pithed rat.},
  author={Kam F. Jim and Richard A. Macia and William D. Matthews},
  journal={The Journal of pharmacology and experimental therapeutics},
  volume={238 1},
The effect of the calcium channel antagonists nifedipine and FR 34235 on the vasopressor response to alpha-1 adrenoceptor stimulation in the pithed normotensive rat was investigated. The maximal pressor response elicited by the full alpha-1 adrenoceptor agonist SK&F l-89748 was slightly but significantly reduced by 1-mg/kg doses of nifedipine (21 +/- 2%) and FR 34235 (34 +/- 4%). In comparison, the maximal pressor response to alpha-1 adrenoceptor stimulation by the partial alpha-1 agonist SK&F… 
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