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

Oleic acid labeled with 14C, (14C-OA) or 131I (131I-OA) and 131I-labeled linoleic acid (131I-LOA) were administered intravenously to rats and tissue distribution studies completed at various time intervals from 5 to 60 min. Tissue distribution of 131-I-labeled oleic acid or linoleic acid was also studied in dogs at 5- and 30-min time intervals after intravenous administration of the tracer dose. There were distinct differences in the patterns of tissue distribution between 14C-OA, 131I-OA, and 131I-LOA. Radioactivity concentration in the myocardium was the highest at all time intervals in the rats given 131I-OA only. In dogs, the myocardial uptake of 131I-OA was significantly higher than the radioactivity in the blood or other tissues at 30 min after injection. The disappearance rates of 131I-OA and 131I-LOA were almost identical but myocardial concentration of 131I-LOA at 30 min after the dose in the dog was half that of 131I-OA whereas 131I-LOA liver concentration was higher than that of 131I-OA. Since the concentrations of our formulated 131I-OA in the blood and in the myocardium are both highest at the earlier intervals, it should be difficult to detect myocardial ischemia or infarction with 131I-OA scanning.
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PMID:Myocardial uptake of labeled oleic and linoleic acids. 115 15

Calcium entry into cardiac cells is believed to be controlled by transmembrane-voltage dependent, protein regulated "channels." The sarcoplasmic reticulum participates in the regulation of cytosolic calcium by ATP dependent Ca2+ sequestration during diastole, and by action potential stimulated calcium release. Massive calcium overloading occurs during reperfusion following myocardial ischemia. Calcium overloading activates phospholipases, which may activate another mechanism involved in lethal cellular injury, that is, the accumulation of long chain fatty acids and their derivatives. These compounds are soluble amphiphiles, and once liberated, they may insert into biological membranes and change membrane composition, physiology, and response to ions and drugs. Sarcoplasmic reticulum vesicles were used as an in vitro model to study the effects of palmitic acid, oleic acid, and palmitylcarnitine on the ability of this membrane system to sequester calcium within the vesicles. In the absence of phosphate, palmitic acid enhanced the ability of the vesicles to sequester calcium. Oleic acid and palmitylcarnitine inhibited calcium sequestration. In the presence of phosphate palmitic acid also inhibited the sequestration of calcium by sarcoplasmic reticulum, although not as severely as oleic acid and palmitylcarnitine. These results suggest that the disturbances in cellular calcium homeostasis following ischemia may be due, in part, to the incorporation of accumulated long chain fatty acids into membranes.
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PMID:The possible role of endogenous amphiphiles in the membrane abnormalities of ischemic and reperfused myocardium. 668 Jun 16

Atherosclerosis, the main cause of ischemic heart disease, is a process with relevant inflammatory components, in which LDL-cholesterol, largely emphasized in the last years as a "causal" factor following the improvement in prognosis with cholesterol-lowering agents, is only one of the culprits. Despite the use of new cholesterol-lowering drugs, atherosclerotic vascular disease will likely continue to be the main cause of death in Western countries. Furthermore, the statistical relationship between cholesterol and cardiovascular mortality only explains a relatively minor component of differences in mortality among diverse countries. For these reasons, the interest in preventive approaches complementary or alternative to cholesterol reduction should be one of the main objectives of cardiovascular research in the years to come. Already in the '70s the very low incidence of atherosclerotic diseases in Mediterranean countries (Greece and Southern Italy) and the importance of the "dietary factor" in such protection were noticed. Diets for people in these countries are, among other components, very rich in oleic acid, the main constituent of olive oil, with about 29% of daily caloric intake derived from monounsaturated fatty acids. Oleic acid, besides exerting relatively minor effects on the quantitative and qualitative regulation of cholesterol levels, appears to interfere directly with the inflammatory response that characterizes early atherogenesis. The endothelial expression of adhesion molecules for circulating monocytes, induced by inflammatory cytokines, minimally oxidized LDL and the advanced glycation end-products present in diabetes, substantially contributes to the onset and early progression of atherosclerosis. In an in vitro model of early atherogenesis based on cultured endothelial cells stimulated by cytokines, we observed that the incorporation of oleic acid in total cell lipids--mostly at the expenses of saturated fatty acids--decreases the expression of several endothelial leukocyte adhesion molecules, among which vascular cell adhesion molecule-1, involved in the selective monocyte recruitment in the arterial intima. Oleic acid also determines a parallel reduction in messenger RNA for this molecule, interfering with the activation of the most important transcription factor controlling endothelial activation, nuclear factor-kappa B. Thus, possibly in concert with other more highly unsaturated fatty acids, oleic acid may contribute to the prevention of atherosclerosis also through a modulation of gene expression for endothelial leukocyte adhesion molecules. This series of investigations emphasizes the possibility of preventive interventions in atherosclerosis based on the modulation of vascular response to classical "triggers" (cholesterol, advanced glycation end-products of diabetes), an intervention strategy fundamentally different from--and thereby complementary to--those now more in fashion.
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PMID:Direct vascular antiatherogenic effects of oleic acid: a clue to the cardioprotective effects of the Mediterranean diet. 1044 51