The role of coronary flow and adenosine in postischemic recovery of septic rat hearts.
Sepsis depresses myocardial function but prevents subsequent ischemia-reperfusion injury. Elevated coronary flow (CF) and endogenous adenosine may be important factors in the complete recovery of postischemic myocardial function observed in septic rat hearts. The purpose of this study was to determine the effects of manipulating CF and of antagonizing adenosine receptors on the postischemic recovery of left ventricular developed pressure (LVDP) in septic and control rat hearts. The relationship between CF and LVDP in septic rat hearts before ischemia was depressed compared with control. However, this relationship was unaltered by ischemia in septic hearts, whereas in control hearts it was severely depressed. Preventing the elevation of CF during reperfusion did not significantly affect the recovery of LVDP in septic rat hearts. Adenosine antagonism by 8-phenyltheophylline (0.1 and 1 nM) prevented the elevated CF during reperfusion, and the higher dose significantly depressed postischemic function. We conclude that elevated CF did not contribute to the recovery of postischemic LVDP in septic rat hearts but that endogenous adenosine may provide protection from ischemia.
Department of Physiology, Louisiana State University Medical Center, New Orleans, Louisiana 70112, USA.
J A
JA
Ismail
K H
KH
McDonough
D000818:Animals; D016470:Bacteremia / Q000150:complications / Q000503:physiopathology*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology*; D004927:Escherichia coli Infections / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D008297:Male; D017202:Myocardial Ischemia / Q000209:etiology / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology; D058915:Purinergic P1 Receptor Antagonists; D051381:Rats; D017207:Rats, Sprague-Dawley; D018047:Receptors, Purinergic P1 / Q000502:physiology*; D012016:Reference Values; D013806:Theophylline / Q000031:analogs & derivatives* / Q000494:pharmacology; D013997:Time Factors; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology*
D058915:Purinergic P1 Receptor Antagonists; D018047:Receptors, Purinergic P1; D013806:Theophylline; C028322:8-phenyltheophylline