Endothelium-dependent higenamine-induced aortic relaxation in isolated rat aorta

Planta Med. 1997 Apr;63(2):130-2. doi: 10.1055/s-2006-957628.


The pharmacological action of higenamine in isolated rat aorta was investigated. Although the beta-adrenoceptor antagonist propranolol (1 x 10(-5) M) completely blocked the beta-adrenoceptor agonist higenamine in inducing a positive chronotropic activity in isolated mouse atria, the higenamine-induced aortic relaxation was not completely antagonized by this concentration of propranolol. The present data also demonstrate that the higenamine-induced aortic relaxation was attenuated in the absence of endothelium. These findings suggest that the beta-adrenoceptor specificity to higenamine in aorta is different from that of beta-1 in atria; moreover, the beta-adrenoceptors sensitive to higenamine are mainly located in the endothelial layer.

MeSH terms

  • Adrenergic beta-Agonists / pharmacology*
  • Adrenergic beta-Antagonists / pharmacology
  • Alkaloids / pharmacology*
  • Animals
  • Aorta / drug effects*
  • Aorta / physiology
  • Endothelium, Vascular / drug effects*
  • Endothelium, Vascular / physiology
  • In Vitro Techniques
  • Male
  • Mice
  • Mice, Inbred ICR
  • Muscle Relaxation / drug effects
  • Muscle Relaxation / physiology
  • Propranolol / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Tetrahydroisoquinolines*


  • Adrenergic beta-Agonists
  • Adrenergic beta-Antagonists
  • Alkaloids
  • Tetrahydroisoquinolines
  • Propranolol
  • higenamine