Coronary effects of vasopressin during partial ischemia and reperfusion in anesthetized goats. Role of nitric oxide and prostanoids.
To examine the coronary effects of arginine-vasopressin and its interaction with nitric oxide and prostanoids during partial ischemia and reperfusion, left circumflex coronary artery flow was electromagnetically measured and partial occlusion of this artery was induced for 60 min, followed by reperfusion in anesthetized goats (seven non-treated, six treated with N(W)-nitro-L-arginine methyl esther (L-NAME) and five with meclofenamate). During partial coronary occlusion, coronary vascular conductance decreased by 20-31% (P<0.01), and the coronary vasodilatation in response to acetylcholine (3-100 ng) and sodium nitroprusside (1-10 microg) was much reduced in every case; the vasoconstriction in response to arginine-vasopressin (0.03-0.3 microg) was attenuated in non-treated animals; this attenuation was reversed by L-NAME and was accentuated by meclofenamate. At 30 min of reperfusion, coronary vascular conductance remained decreased by 11-25% (P<0.05 or P<0.01), and the vasodilatation in response to acetylcholine and sodium nitroprusside as well as the vasoconstriction with arginine-vasopressin was as in the control and comparable in the three groups of animals. These results suggest: (1) that, during ischemia, the coronary vasodilator reserve is greatly reduced and the vasoconstriction with arginine-vasopressin is attenuated, with preservation of the modulatory role of nitric oxide and probable involvement of vasoconstrictor prostanoids in this vasoconstriction; and (2) that, during reperfusion, the coronary vasodilator reserve and the coronary reactivity to acetylcholine and arginine-vasopressin recover, but the modulatory role of nitric oxide in this reactivity may be attenuated.
Martínez
María Angeles
MA
Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma, Arzobispo Morcillo, 2, 28029 Madrid, Spain.
Fernández
Nuria
N
Climent
Belén
B
García-Villalón
Angel-Luis
AL
Monge
Luis
L
Sanz
Elena
E
Diéguez
Godofredo
G
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology*; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology; D005260:Female; D006041:Goats; D006439:Hemodynamics / Q000187:drug effects; D008469:Meclofenamic Acid / Q000494:pharmacology; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology; D011453:Prostaglandins / Q000378:metabolism*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology
D011453:Prostaglandins; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D001127:Arginine Vasopressin; D009599:Nitroprusside; D009569:Nitric Oxide; D008469:Meclofenamic Acid; D000109:Acetylcholine; D019331:NG-Nitroarginine Methyl Ester