Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of hyaluronidase (H) on subacute experimental myocardial ischemia was studied in isolated perfused rabbit hearts. Changes in ischemic area were assessed by epicardial nicotinamide adenine dinucleotide (NADH) fluorescence photography, an intrinsic high-resolution display of myocardial ischemia. Computerized determination of ischemic area was made from standardized photographs. Hyaluronidase was begun 20 minutes after coronary artery occlusion at 4 units/ml perfusate. NADH fluorophotographs were taken at 10-minute intervals up to 60 minutes of ischemia. Coronary sinus oxygen tension (PcsO2), myocardial oxygen consumption (MVO2), and coronary flow were determined. After 70 minutes, the hearts were perfused with rhodamine solution to identify areas of myocardial perfusion. In 13 H-treated hearts 54.3% +/- 3.7% (mean +/- SEM) of the nonperfused area (rhodamine stained) was ischemic (NADH fluorescent). In 14 untreated hearts 79.8% +/- 3.2% of the nonperfused area was ischemic (p less than 0.0001) and the ischemic areas were uniform. The distance between perfused and ischemic tissue was 952 +/- 78 micrometers in the H hearts and 504 +/- 35 micrometers in the untreated heart (p less than 0.0001). In the H hearts PcsO2 increased to 155% of the post-ligation control while it decreased to 79% in the untreated hearts (p less than 0.0001). MVO2 decreased in the H-treated hearts to 62%; the untreated hearts had no further change. In the H-treated hearts, coronary flow increased to 146% of the post-ligation control while it fell to 91% in the untreated group (p less than 0.0001). We conclude that H increases coronary flow while decreasing MVO2 during subacute ischemia. In H-treated hearts, significant amounts of myocardium remain normoxic within the nonperfused areas, and may potentially be salvaged after prolonged myocardial ischemia.
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PMID:Mechanism of action of hyaluronidase in decreasing myocardial ischemia post coronary occlusion in the isolated perfused rabbit heart. 711 92

Hyaluronidase has been reported to be beneficial in reducing injury to the ischemic myocardium in several experimental studies. This effect may involve an enhancement in either the cardiac blood supply or lymphatic flow or a combination there of. In this experiment, a baboon open chest model of myocardial ischemia and reperfusion was used to determine if treatment with hyaluronidase would result in a reduction in infarct size. Baboons underwent occlusion of the left anterior descending coronary artery for 2 hr. Fifteen minutes after occlusion, a treated group (n = 6) received bovine testicular hyaluronidase (500 national formulary units/kg) i.v. over a 10-min period. The ischemic period was followed by 22 hr of reperfusion. A control group (n = 8) underwent the same protocol minus the hyaluronidase infusion. At the end of the reperfusion period, the hearts were excised and the perfusion bed at risk for infarction was determined by the infusion of a microvascular dye. The hearts were then sectioned and stained for the histological determination of infarct size. The volume of the perfusion bed infarcted was 66 +/- 7% in the control group compared with 42 +/- 10% in the treated group (P > 0.05). In this study using a primate model that has a minimal collateral blood supply, hyaluronidase did not significantly reduce the ultimate infarct size.
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PMID:Effects of hyaluronidase on reducing myocardial infarct size in a baboon model of ischemia-reperfusion injury. 786 74