| Autor: |
G J, Gross, D C, Warltier, H F, Hardman |
| Rok vydání: |
1976 |
| Předmět: |
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| Zdroj: |
The Journal of pharmacology and experimental therapeutics. 196(2) |
| ISSN: |
0022-3565 |
| Popis: |
The present study was designed to determine the effect of adenosine on oxyhemoglobin equilibrium (P-50) and myocardial oxygen consumption (MVO2) in the isolated supported dog heart preparation perfused at a constant coronary blood flow. Heart rate was controlled at 150 beats/min. A-3-minute intracoronary infusion of adenosine (10, 50 and 100 mug/min) produced significant decreases in MVO2, whereas coronary venous P-50 did not change. Adenosine-5'-monophosphate (5'-AMP) infusion (70 and 140 mug/min) did not produce a significant change in MVO2. Both adenosine and 5'-AMP caused equivalent decreases in coronary artery perfusion pressure and peak left ventricular systolic pressure. Furthermore, adenosine (50 and 100 mug/min) produced a significant decrease in MVO2 of the isolated supported fibrillating heart. These results suggest that the reduction in MVO2 observed with adenosine is not related to coronary vasodilation or to a negative inotropic or chronotropic action. Theophylline (2.5 mg/kg) partially blocked the hemodynamic effects of adenosine while completely abolishing the decrease in MVO2. Neither inosine nor hypoxanthine (50 and 100 mug/min) changed MVO2, P-50 or myocardial hemodynamics. Thus, in addition to its proposed role in coronary blood flow regulation, adenosine appears to exert important effects on myocardial metabolism. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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