Myocardial surface oxygen pressure across the border zone in the pig during acute coronary artery occlusion. A comparison of pretreatment with metoprolol or isoprenaline
- 22 Downloads
Tissue oxygen pressure was measured in the pig heart during repeated coronary artery occlusions. ptO2 was measured with an array-multiwire-electrode across the border zone, i.e. the transition zone between normal and ischaemic myocardium. The LAD was occluded three times, each lasting 5 min and with 55 min of reperfusion between the occlusions. Three groups of animals were studied: Group 1 served as controls; Group 2 were given metoprolol 0.3 mg/kg i.v. after the first LAD occlusion; Group 3 were given isoprenaline in a continuous infusion, started after the first LAD occlusion and continued throughout the rest of the experiment.
Heart rate differed as expected between the two treated groups. The pattern of ptO2 values across the border zone repeated itself for each animal. No change in the pattern of ptO2 values was seen in either treatment group. In conclusion, there were no indications that it was possible to change the ptO2 of the border zone in the pig heart either with metoprolol or isoprenaline in the doses used.
Key wordstissueoxygen pressure coronary artery occlusion pig array-multiwire-electrode border zone metoprolol isoprenaline myocardialischaemia
Unable to display preview. Download preview PDF.
- 2.Chance B (1976) Border zone (Discussion). Circ Res 38 (suppl 1):69–72Google Scholar
- 3.Engelhardt W v (1966) Swine cardiovascular physiology—A review. In: Bustad LK, McClellan R (eds) Swine in biomedical research. Richland, Washington: Battelle North WestGoogle Scholar
- 14.Kessler M, Lübbers DW (1966) Aufbau und Anwendungsmöglichkeiten verschiedener pO2-Electroden. Pflügers Arch Ges Physiol R82:291Google Scholar
- 18.Opie LH (1976) Effects of regional ischemia on metabolism of glucose and fatty acids. Relative rates of aerobic and anaerobic energy production during myocardial infarction and comparison with effects of anoxia. Circ Res 38 (suppl 1):52–68Google Scholar
- 21.Jennings RB, Reimer KA (1978) Effect of betaadrenergic blockade on acute myocardial ischemic injury. In: Gross F (ed) Modulation of Sympathetic Tone in the Treatment of Cardiovascular Diseases. Hans Huber Publishers Bern Stuttgart Vienna, pp 103–114Google Scholar
- 29.Walfridsson H, Lewis DH, Sjöberg F, Lund N (1985) Acute coronary artery occlusion: oxygen pressure in the border zone studied in the pig. Int J Microcirc, Clin Exp 4:109–119Google Scholar
- 31.Walfridsson H, Ödman S (1987) Myocardial oxygen pressure across the border zone during acute coronary occlusion in the pig heart. Int J Microcirc, Clin Exp 6:57–65Google Scholar