Ex Vivo Tension Recording

The DMT 620M Wire Myograph™ system is used to conduct ex vivo vascular ring tension recording on multiple vessel types including the aorta, the pulmonary artery and the middle cerebral artery.  The highly sensitive, flexible system can accommodate vessels down to 100 μm in diameter.  Relaxation and contractile activity are measured using force transducers. The system:

  • Allows ex vivo study of compound activity on vascular function
  • Enables assessment of antagonist potency for receptor/agonist combinations in both naïve and diseased model tissues
  • Assess vascular remodeling and function via pharmacologic challenge or evaluating length-tension relationships from therapeutic or prophylactic in vivo studies

Contraction and relaxation, measured in grams of force, are recorded overtime in response to various agonists, such as phenylephrine and acetylcholine.  

DOCA + Salt Aortic Endothelial Dysfunction

  • Acetylcholine (ACh) is an endothelium-dependent vasodilator, and acts through stimulating production of nitric oxide
  • ACh elicits concentration-dependent, complete relaxation of phenylephrine (PE) pre-constricted aortic rings from naïve rats (black symbols). Physically denuding naïve aortic rings (white symbols) ablates ACh-mediated relaxation, indicating that this response is endothelium-dependent
  • Aortic rings from DOCA-NaCl hypertensive rats (green symbols) demonstrate impaired relaxation in response to ACh relative to naïve controls, indicating hypertension-induced endothelial dysfunction
  • This approach may be leveraged to evaluating effects of test agents to improve endothelial function