Ischemic region

Although liver uptake of this compound is relatively high, the ischemic regions of the heart were visualized. SPECT images obtained from cats that were administered BMS-181321 one hour after middle cerebral artery occlusion (MCAO) showed selective brain retention in the ischemic territory of the MCA... 

Tse et al. [130] have reported that transendocar-dial injection of autologous BMMNCs in eight patients with severe ischemic heart disease led to preserved left ventricular function. At 3-month follow-up, heart failure symptoms and myocardial perfusion had improved, especially in the ischemic region as shown by cardiac MRI. 

It enhances cholinergic transmission and improves cerebral microcirculation in ischemic regions. It protects the neurons against hypoxia disturbance of glucose metabolism. 

Heart muscle fibers are coupled by gap junctions. These intercellular channels provide the exchange of small molecules (<1,000 D), like second messengers, between the cells and they allow electrical coupling. Thus, these cells connected to each other form a syncytium. However, from mapping studies it became evident that under certain conditions, e.g. regional ischemia, the ischemic region uncouples. In addition, mapping studies demonstrated that there is a special activation pattern which accounts for a directed activation of the whole heart. This activation pattern exhibits a considerable similarity from beat to beat. It is well known that the conduction velocity varies between... 

Giordano, F.J., Ping, P., McKiman, M.D., Nozaki, S., DeMaria, A.N., Dillman, W.H. et al. (1996) Intracoronary gene transfer of fibroblast growth factor-5 increases blood flow and contractile function in an ischemic region of the heart. Nat. Med., 2, 534-539. 

Fig. 1. BEO dose-dependently reduces infarct size after permanent MCAo. Representative images of brain sections from (A) rats in — 5) sacrificed 24 h after permanent occlusion of middle cerebral artery (24 h MCAo) and (B) BEO-treated rats (n — 5) prior to MCAo BEO (0.5 ml/kg) was administered i.p. 1 h before MCAo. Brain sections were stained by TTC the ischemic region appears as a pale-stained area whereas the viable tissue is stained red. (C) Effects of different doses of BEO (0.05—1 ml/kg), administered i.p. 1 h before MCAo, on infarct volume results are expressed as mean S.E.M. (n = 4-6 per group). and Denote P< 0.05 andP< 0.01 versus 24 h MCAo, respectively (ANOVA followed by Dunnett multiple comparisons test).

Halothane, isoflurane, and sevoflurane are potent coronary vasodilators, able to produce some degree of coronary steal in ischemic regions. Despite this, halothane may preferentially dilate large coronary arteries and/or interfere with platelet aggregation. If these experimental effects are confirmed, halothane may be the anesthetic of choice in the non-failing ischemic heart (3). 

The major determinants of cardiac oxygen consumption are heart rate, myocardial wall tension (directly related to ventricular cavity pressure and volume) and force and velocity of contraction. Under normal conditions, the heart extracts oxygen at a near-maximal rate and added requirements are met by a reduction in coronary vascular resistance and an increase in blood flow. In the atherosclerotic heart, coronary vessels in the ischemic region and particularly in the subendocarium are already dilated and their ability to increase flow by further dilatation is severely compromised. Thus, under these conditions, increasing oxygen demand may exceed supply, myocardial ischemia ensues and the patient manifests symptoms of angina pectoris. 2... 

Giordano F), Ping P, McKirnan MD, et al. Intracoronary gene transfer of fibroblast growth factor-5 increases blood flow and contractile function in an ischemic region of the heart. 

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