Posts Tagged ‘Ischemia

RESULTS   Because changes in the hemodynamic variables produced by myocardial ischemia and by NONLA were measured in the same animal and changes in coronary flow were measured in the same ventricular transmural layers in each dog, the results were analyzed by Student’s paired t test. The null hypothesis was discarded with P<0.05. Results are […]

The effect of NONLA was considered adequate when the response of circumflex coronary flow to the intracoronary administration of acetylcholine (5.5 nmol/kg diluted in 0.5 mL saline) was reduced by at least 80% . Fifteen minutes later ischemia was again induced by decreasing the peripheral coronary pressure, and regional flow was measured with the microspheres […]

Experimental design: After the surgical procedure a period of 15 mins was allowed for hemodynamic variables to stabilize. The following protocol was followed in each of the 14 dogs. Ischemia was induced by decreasing the peripheral coronary pressure with the occluder from its control value to a pressure of about 25 mmHg. After 1 min […]

A mechanical occluder was placed distal to the flowmeter in order to produce a controlled decrease in coronary flow. Pressure distal to the occluder (peripheral coronary pressure) was measured with a pressure transducer (Statham P23 Db) through an outlet in the connection. Arterial PO2, PCO2 and pH were frequently measured in samples drawn from the […]

ANIMALS AND METHODS The present study was conducted in accordance with the “Position of the American Heart Association on Research and Animal Use” and the guidelines of the Animal Care Committee of the Faculty of Medicine of the University of Chile. Surgical preparation of dogs: Fourteen mongrel dogs of either sex between 11 and 17 […]

Nitric oxide participates in the regulation of coronary bloodflow during reactive hyperemia . This observation may imply that the release of nitric oxide is mediated by ischemia as a regulatory mechanism between the myocardial cell and the endothelial cell. However, it is uncertain whether the stimulus for production of nitric oxide in the endothelium during […]