Faculty Collaboration Database

Oxygen-derived free radicals contribute to neural stunning in the canine heart. Am J Physiol 1997 Sep;273(3 Pt 2):H1569-75

Date

10/10/1997

Pubmed ID

9321851

DOI

10.1152/ajpheart.1997.273.3.H1569

Scopus ID

2-s2.0-33751300311 (requires institutional sign-in at Scopus site)   5 Citations

Abstract

Oxygen-derived free radicals (ODFR) contribute to delayed recovery of myocardial function after brief ischemia. We examined the effect of ODFR scavengers on ischemia-induced dysfunction of cardiac sympathetic nerves. Mongrel dogs were anesthetized and instrumented for recording heart rate, arterial pressure, systolic wall thickening, and left anterior descending coronary artery (LAD) and left circumflex coronary artery (LCX) flow velocities. Bilateral stellate stimulation was performed, measuring changes in an index of coronary vascular resistance (% delta CVR) before and after 15 min of LAD occlusion. Superoxide dismutase (SOD) and catalase (CAT) were infused intravenously for 30 min beginning 10 min before occlusion. With vehicle (n = 13), % delta CVR was significantly attenuated in LAD after ischemia and 30-min reperfusion [39 +/- 3 to 13 +/- 2%, P < 0.05; for LCX, 42 +/- 4 to 45 +/- 7%, P = not significant (NS)]; however, no attenuation was seen in dogs in which SOD and CAT were infused (n = 10; for LAD, 39 +/- 5 to 41 +/- 5%; for LCX, 46 +/- 7 to 47 +/- 6%; P = NS). Baseline and stimulated changes in hemodynamics were similar between groups. The % delta CVR in the LCX (control) bed was not affected by SOD and CAT. Recovery of myocardial function (percent of baseline) was greater in SOD and CAT after reperfusion (26 +/- 16% vs. -30 +/- 11% at 90 min of reperfusion, P < 0.05). We conclude that ODFR contribute not only to myocardial stunning but also to neural stunning of sympathetic cardiac innervation after brief ischemia.

Author List

Miura H, Morgan DA, Gutterman DD

MESH terms used to index this publication - Major topics in bold

Animals
Blood Flow Velocity
Blood Pressure
Catalase
Coronary Vessels
Dogs
Electric Stimulation
Female
Free Radical Scavengers
Heart Rate
Hemodynamics
Infusions, Intravenous
Male
Myocardial Ischemia
Myocardial Stunning
Propranolol
Stellate Ganglion
Superoxide Dismutase
Systole
Vascular Resistance
Vasoconstriction
Ventricular Function, Left