Short ischemia causes endothelial dysfunction in porcine coronary vessels in an in vivo model.
BACKGROUND
The aim of this study was to evaluate the effects of a short period of ischemia (10 mins) and a prolonged period of ischemia (60 mins) followed by reperfusion on coronary flow changes induced by acetylcholine (ACh), adenosine (ADO), and endothelin (ET).


METHODS
The left anterior descending coronary artery in anesthetized pigs was occluded for 10 or 60 minutes followed by 120 minutes reperfusion. Thereafter, the flow changes in the left anterior descending coronary artery were studied after intracoronary infusion of ACh, ADO, and ET.


RESULTS
Short-term ischemia (10 minutes) caused a decrease in vasodilatation, but not the vasoconstriction response to ACh. Prolonged ischemia (60 minutes) impaired ADO induced vasodilatation and aggravated ET evoked vasoconstriction.


CONCLUSIONS
The present findings suggest that a short period of ischemia (10 minutes) causes disturbances of the endothelial regulation of coronary vascular tone and that this endothelial regulation is more sensitive, and precedes changes in vascular smooth muscle function after ischemia and reperfusion.
Lockowandt
U
U
Department of Thoracic Surgery, Karolinska Hospital, Stockholm, Sweden. ulf.lockowandt@ks.se
Liska
J
J
Franco-Cereceda
A
A
D000818:Animals; D002315:Cardiopulmonary Bypass; D003331:Coronary Vessels / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D007511:Ischemia / Q000503:physiopathology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000503:physiopathology; D015425:Myocardial Reperfusion; D011897:Random Allocation; D013552:Swine; D013997:Time Factors; D014664:Vasodilation