Effects of short-term, diet-induced hypercholesterolemia on systemic hemodynamics, myocardial blood flow, and infarct size in awake dogs with acute myocardial infarction
| Autor: | Chang-seng Liang, N. Imai, M. Kashiki, S. Sakamoto, W. B. Hood |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
medicine.medical_specialty
Hypercholesterolemia Myocardial Infarction Hemodynamics Anterior Descending Coronary Artery chemistry.chemical_compound Dogs Coronary Circulation Physiology (medical) Internal medicine Occlusion medicine Animals Myocardial infarction biology business.industry Cholesterol Fissipedia Blood flow biology.organism_classification medicine.disease Collateral circulation chemistry Cardiology Diet Atherogenic Cardiology and Cardiovascular Medicine business |
| Zdroj: | Circulation. 84:378-386 |
| ISSN: | 1524-4539 0009-7322 |
| DOI: | 10.1161/01.cir.84.1.378 |
| Popis: | BACKGROUND Short-term cholesterol feeding has been shown to affect vasomotor tone and increase infarct size in anesthetized rabbits. The purpose of the study was to determine whether acute hypercholesterolemia reduced collateral flow to ischemic myocardium and increased infarct size in the awake dog. METHODS AND RESULTS Acute myocardial infarction was produced in awake dogs by a 4-hour left anterior descending coronary artery occlusion followed by 6-hour reperfusion after either a cholesterol-supplemented diet (n = 14) or a control diet of dog chow (n = 15) for 10 days. Infarct size was determined using nitroblue tetrazolium staining. In two subgroups, a 15-minute transient occlusion of the left anterior descending coronary artery was produced before the diet treatments and was compared with occlusion after diet treatments, so that the effects of hypercholesterolemia of collateral flow could be determined by paired comparisons. Cholesterol feeding increased plasma cholesterol to 288 +/- 52 mg/dl, which was twofold to threefold that in the control group (127 +/- 35 mg/dl), but had no effects on baseline systemic hemodynamics and myocardial blood flow. Coronary artery occlusion produced similar increases in heart rate, mean aortic pressure, left atrial pressure, and plasma norepinephrine in both groups of animals. However, cholesterol feeding reduced collateral flow to ischemic myocardium and increased infarct size, compared with the control group. The infarct size correlated with ischemic myocardial blood flow in both groups, but the slopes of regression lines relating the two variables did not differ between the two groups. CONCLUSIONS Short-term, diet-induced hypercholesterolemia increased infarct size in awake dogs. This change results, at least in part, from a decrease in collateral blood flow to ischemic myocardium during coronary artery occlusion. |
| Databáze: | OpenAIRE |
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