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)

Cardiac lymph was obtained from 12 normal dogs (group 1) for two consecutive 2-h control periods and from 7 dogs (group 2) for 2 h before and 2 h after occlusion of the circumflex branch of the left coronary artery. Lymph composition was studied with reference to pH, red blood cell (RBC) concentration, total protein content, potassium and sodium ion concentrations, and creatine phosphokinase (CPK) and acid phosphatase enzyme activities. No significant difference was noted in any variable between the two groups during the firts 2-h period. In group 1, no significant changes occurred in any variable as a result of the passage of time alone. In group 2, 2 h of myocardial ischemia produced increases of 53.3 plus or minus 5.1% in lymph flow, 67 plus or minus 5% in protein content, and 418 plus or minus 27% in the RBC concentration, suggesting increased blood capillary permeability. Lactate rose 120.5 plus or minus 27%, potassium concentration increased 16.9 plus or minus 2.4%, acid phosphatase increased 30 plus or minus 3%, and CPK rose 61.6 pluse or minus 10.9%, suggesting ischemic injury of myocardial cells. These changes in lymph were statistically significant (P LESS THAN 0.05) and reflect both capillary and myocardial cell abnormalities.
 ...
PMID:Cardiac lymph flow and composition in acute myocardial ischemia in dogs. 23 6

It has been proposed that administration of pharmacologic doses of glucocorticoids may be beneficial in the setting of acute myocardial ischemia because of their ability to stabilize lysosomal membranes and thereby to prevent the leakage of proteolytic enzymes into the cytoplasm and interstitium. We collected cardiac lymph in anesthetized open-chest dogs in successive 2-h periods and used acid phosphatase as our marker lysosomal enzyme. In group 1 (n=5), we studied the effect of time alone. In these dogs, the total amount of acid phosphatase decreased (P less than 0.05). In group 2 (n=5), methylprednisolone, 30 mg/kg iv, was given. This drug did not change any variable we measured. Ligation of the circumflex coronary artery in group 3 (n=7), produced a significant increase (P less than 0.05) in the amount of acid phosphatase drained from the heart compared to group 1. In the dogs of group 4 (n=5), methylprednisolone did not reduce, and may have augmented, the total amount of acid phosphatase draining from the heart. Thus glucocorticoids do not appear to reduce the amount of acid phosphatase released by the ischemic myocardium into the cardiac lymph.
 ...
PMID:Effects of methylprednisolone on cardiac lymph in acute myocardial ischemia in dogs. 87 99

The pathobiology of the process of myocardial injury during ischemia comprises a series of events that results in the release of lysosomal enzymes from their subcellular locations within the myocardium. We have developed a canine model of acute myocardial ischemia in which the anterior descending coronary artery is ligated, myocardial blood flow is measured using radioactive microspheres, and tissues from subendocardium and subepicardium are assayed for activity of lysosomal hydrolases:N-acetyl-beta-glucosaminidase (NAG), beta-glucuronidase (beta-gluc), and acid phosphatase (AP). Particulate fractions of subendocardium revealed significant depletion of of total acid hydrolases (NAG, beta-gluc, and AP) after one and two hours of ischemia. In addition, after two hours of ischemia, the total activity of these three hydrolases in the subendocardial supernatant was decreased, correlating significantly with diminished myocardial blood flow (NAG: r =0.96; beta-gluc: r = 0.95; AP: r = 0.75). The diminished enzymatic levels in thesupernatant suggested "washout" of the hydrolases that was more efficient in those ischemic areas that had higher myocardial flow (greater than 20% of control). These changes in distribution of lysosomal hydrolases indicate early involvement of these enzymes in the pathobiology of myocardial injury and demonstrate the dynamic relationship of "washout" of acid hydrolases with the degree of diminished blood flow.
 ...
PMID:Release of lysosomal enzymes during ischemic injury of canine myocardium. 103 97

In this study, S-allyl cysteine sulfoxide (SACS) was used to evaluate its preventive effect in isoproterenol (ISO)-induced myocardial ischemia in male Wistar rats. Rats were pretreated with SACS (40 and 80 mg kg(-1)) orally for 5 weeks. After the treatment period, ISO (150 mg kg(-1)) was administered subcutaneously to rats at an interval of 24 h for 2 days. The activities of beta-D-N-acetyl-glucosaminidase, beta-galactosidase, beta-glucosidase, and acid phosphatase increased in serum and heart in ISO-induced rats. In addition, these rats showed a significant (p < 0.05) increase in the activities of beta-glucuronidase and cathepsin-D in serum and heart and a significant (p < 0.05) decrease in their activities in lysosomal fraction of the heart. The activity of Na(+)K(+)-ATPase declined, while those of Ca(2+)- and Mg(2+)-ATPases significantly (p < 0.05) elevated in the heart of ISO-induced rats. Pretreatment with SACS (40 and 80 mg kg(-1)) showed a significant (p < 0.05) effect in all the biochemical parameters studied. The effect at a dose of 80 mg kg(-1) body weight was more effective than that at 40 mg kg(-1) body weight and brought back all the biochemical parameters to near normal levels. Hereby, our study shows the membrane-stabilizing as well as antioxidant effects of SACS in ISO-induced rats.
 ...
PMID:Preventive effect of S-allyl cysteine sulfoxide (alliin) on lysosomal hydrolases and membrane-bound ATPases in isoproterenol-induced myocardial infarction in Wistar rats. 1762 87

The aim of this study was to evaluate the time course events of cellular damage during myocardial ischemia and reperfusion injury in rats and to find out a correlation between the structural alterations with respect to the biochemical changes. Cardiac biomarkers and lysosomal enzymes viz. cathepsin D, acid phosphatase and beta-glucuronidase and matrix metalloproteinases (MMPs) were evaluated at different time points, in response to ischemia-reperfusion induced oxidative stress in an isolated rat heart model perfused in Langendorff mode. Microscopically, changes in myocardial architecture, myofibrillar degradation, and collagen (COL) integrity were studied using hematoxylin-eosin, Masson's trichrome and toluidine blue staining techniques. A three-fold increase in the level of myoglobin was observed after 30 min of ischemia followed by 120 min of reperfusion as compared to 15 min ischemia, 120 min reperfusion. Similarly, a significant increase (P<0.05) in the levels of lipid peroxides and superoxide anion coupled with a decrease in enzymatic and nonenzymatic antioxidant levels were observed. A concomitant increase in the activity of cathepsin D (24.07+/-0.95) and a higher expression of MMPs after 120 min of reperfusion following 30 min ischemia were shown to correlate with the myocardial damage as shown by histopathology, suggesting that free radical induced activation of cathepsin D and MMPs could mediate early damage during myocardial ischemia and reperfusion.
 ...
PMID:Myocardial ischemia and reperfusion injury in rats: lysosomal hydrolases and matrix metalloproteinases mediated cellular damage. 1834 82