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Updated: Aug 23, 2026
Isolation and Culture of Primary Endothelial Cells from Canine Arteries and Veins
Published on: November 18, 2016
Endothelium-dependent vasodilation during acute rejection in dogs
Paul J Pearson1, Chi-Ming Wei, Pyng J Lin
1Division of Cardiovascular Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
Background:
Acute rejection, which is a major cause of death after cardiac transplantation, is associated with increased coronary artery resistance and decreased coronary blood flow, leading to congestive heart failure.
Materials And Methods:
To examine the contribution of endothelium-derived vasoactive factors on coronary artery tone during acute rejection, dogs underwent orthotopic heart transplantation without immunosuppression. Plasma levels of endothelin, a potent endogenous vasoconstrictor peptide, and atrial natriuretic peptide, an endogenous coronary vasodilator of cardiac origin, were measured daily by radioimmunoassay until sacrifice.
Results:
Over 7 days, all animals developed acute rejection accompanied by progressive increases in plasma endothelin (10 +/- 3 to 25 +/- 4 pg/ml, n = 6, P < 0.05) and atrial natriuretic peptide (57 +/- 10 to 188 +/- 42 pg/ml, n = 6, P < 0.05). However, in organ chamber experiments, coronary artery segments from rejecting hearts exhibited normal endothelium-dependent vasodilation to acetylcholine, adenosine diphosphate, and the calcium ionophore A23187. In addition, coronary arteries exhibited normal relaxation to sodium nitroprusside (cyclic guanosine monophosphate-dependent) and isoproterenol (cyclic adenosine monophosphate-dependent).
Conclusions:
In early, untreated acute rejection after orthotopic heart transplantation, graft dysfunction is not associated with impaired endothelium-dependent coronary artery vasodilation but may result from enhanced production of endothelin, a potent vasoconstrictor.
